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  • 1.
    Abrahamsson, Pernilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Optimised sample handling in association with use of the CMA 600 analyser2008Ingår i: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 48, nr 5, s. 940-945Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large degree of variability for batched analysis of serially collected microdialysis samples measured with the CMA 600 analyser has been described. This study was designed to identify sources of variability related to sample handling. Standard concentrations of four solutes were placed in microdialysis vials and then stored and analysed at intervals. Results were analysed for variability related to vial and cap type, duration and temperature of storage, centrifugation and re-analysis. The main results were that centrifugation of samples reduced variability. When a batch of 24 samples was analysed, the use of crimp caps reduced evaporation. Samples in glass vials with crimp caps could be stored in a refrigerator for up to 14 days without large variability in concentration compared to plastic vials which demonstrated variability already when stored for more than 1 day. We conclude that variability in microdialysis results can occur in relation to storage and analysis routines if routines are not optimised concerning evaporation. Centrifugation before analyses, glass vials with crimp caps even during frozen storage, and attention to minimal times for samples to be uncapped during analysis all contribute to minimise variability in the handling and analysis of microdialysis samples.

  • 2.
    Abrahamsson, Pernilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Blind, Per Jonas
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Outcome of microdialysis sampling on liver surface and parenchyma2016Ingår i: Journal of Surgical Research, ISSN 0022-4804, E-ISSN 1095-8673, Vol. 200, nr 2, s. 480-487Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: To investigate whether surface microdialysis (μD) sampling in probes covered by a plastic film, as compared to noncovered and to intraparenchymatous probes, would increase the technique's sensitivity for pathophysiologic events occurring in a liver ischemia-reperfusion model. Placement of μD probes in the parenchyma of an organ, as is conventionally done, may cause adverse effects, e.g., bleeding, possibly influencing outcome.

    Methods: A transient ischemia-reperfusion model of the liver was used in six anesthetized normoventilated pigs. μD probes were placed in the parenchyma and on the liver surface. Surface probes were either left uncovered or were covered by plastic film.

    Results: Lactate and glucose levels were significantly higher in plastic film covered probes than in uncovered surface probes throughout the ischemic period. Glycerol levels were significantly higher in plastic film covered probes than in uncovered surface probes at 30 and 45 min into ischemia.

    Conclusions: Covering the μD probe increases the sensibility of the μD–technique in monitoring an ischemic insult and reperfusion in the liver. These findings confirm that the principle of surface μD works, possibly replacing need of intraparenchymatous placement of μD probes. Surface μD seemingly allows, noninvasively from an organ's surface, via the extracellular compartment, assessment of intracellular metabolic events. The finding that covered surface μD probes allows detection of local metabolic changes earlier than do intraparenchymatous probes, merit further investigation focusing on μD probe design.

  • 3.
    Abrahamsson, Pernilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Waldenström, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Detection of myocardial ischaemia using surface microdialysis on the beating heart2011Ingår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 31, nr 3, s. 175-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Microdialysis (MD) can be used to study metabolism of the beating heart. We investigated whether microdialysis results obtained from epicardial (surface) sampling reflect acute changes in the same way as myocardial sampling from within the substance of the ventricular wall. In anaesthetized open-thorax pigs a coronary snare was placed. One microdialysis probe was placed with the sampling membrane intramyocardially (myocardial), and a second probe was placed with the sampling membrane epicardially (surface), both in the area which was made ischaemic. Ten minutes collection intervals were used for microdialysis samples. Samples from 19 pigs were analysed for lactate, glucose, pyruvate and glycerol during equilibration, baseline, ischaemia and reperfusion periods. For both probes (surface and myocardial), a total of 475 paired simultaneous samples were analysed. Results from analyses showed no differences in relative changes for glucose, lactate and glycerol during baseline, ischaemia and reperfusion. Surface microdialysis sampling is a new application of the microdialysis technique that shows promise and should be further studied.

  • 4.
    Abrahamsson, Pernilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Blind, Per-Jonas
    Kirurgi, Skåne Universitets sjukhus, Lund.
    Comparison between outcome of  surface and intraparenchymatous sampling using microdialysis in an experimental liver ischemia modelManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Introduction. We recently have shown that samples from MD probes placed on the surface of the heart reflect metabolic events in the myocardium. This new interesting observation challenges us to consider whether surface application of MD applies to other parenchymatous organs and their surfaces.

    Material and methods.  In thirteen anesthetized pigs transient liver ischemia was achieved by occlusion of arterial and venous inflow to the liver. Two probes on liver surface, and two in parenchyma were perfused with a flow rate of 1 µL/min (n=13). An identical set up was used for probes with a flow rate of 2 µL/min (n=9). Samples were collected for every 15 minute period during 60 minutes of baseline, 45 minutes of ischemia and 60 minutes of reperfusion. Lactate, glucose, pyruvate and glycerol were analysed in MD samples. We focused on relative changes in the present paper.

    Results. There was a strong agreement in relative lactate and glucose levels between probes placed on liver surface and parenchyma. No significant differences in relative changes of lactate and glucose levels were seen between samples from surface probes and probes in liver parenchyma during equilibration, baseline, ischemia or reperfusion with a flow rate of 1 µL/min.

    Conclusion. MD sampling applied on the liver surface is a new application area for the MD technique, and may be used to monitor liver metabolism both during physiological and pathophysiological conditions.

  • 5.
    Abrahamsson, Pernilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Blind, Per-Jonas
    Surface microdialysis sampling: a new approach described in a liver ischaemia model2012Ingår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 32, nr 2, s. 99-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We recently have shown that samples from microdialysis (MD) probes placed on the surface of the heart reflect metabolic events in the myocardium. This new interesting observation challenges us to consider whether surface application of MD applies to other parenchymatous organs and their surfaces. In 13 anesthetized pigs, transient liver ischaemia was achieved by occlusion of arterial and venous inflow to the liver. Two probes on liver surface and two in parenchyma were perfused with a flow rate of 1 mu l per min (n = 13). An identical set-up was used for probes with a flow rate of 2 mu l per min (n = 9). Samples were collected for every 15-min period during 60 min of baseline, 45 min of ischaemia and 60 min of reperfusion. Lactate, glucose, pyruvate and glycerol were analysed in MD samples. We focused on relative changes in the present study. There was a strong agreement in relative lactate and glucose levels between probes placed on liver surface and those on parenchyma. No significant differences in relative changes in lactate and glucose levels were seen between samples from surface probes and probes in liver parenchyma during equilibration, baseline, ischaemia or reperfusion with a flow rate of 1 mu l per min. MD sampling applied on the liver surface is a new application area for the MD technique and may be used to monitor liver metabolism during both physiological and pathophysiological conditions.

  • 6.
    Ahlström, Katarina
    et al.
    Anesthesia and Intensive Care Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Biber, Björn
    Anesthesia and Intensive Care Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Ronquist, Gunnar
    Department of Medical Chemistry, Uppsala University, Uppsala, Sweden.
    Waldenström, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Haney, Michael F.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Exogenous carbon monoxide does not affect cell membrane energy availability assessed by sarcolemmal calcium fluxes during myocardial ischaemia-reperfusion in the pig2011Ingår i: European Journal of Anaesthesiology, ISSN 0265-0215, E-ISSN 1365-2346, Vol. 28, nr 5, s. 356-362Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Carbon monoxide is thought to be cytoprotective and may hold therapeutic promise for mitigating ischaemic injury. The purpose of this study was to test low-dose carbon monoxide for protective effects in a porcine model of acute myocardial ischaemia and reperfusion.In acute open-thorax experiments in anaesthetised pigs, pretreatment with low-dose carbon monoxide (5% increase in carboxyhaemoglobin) was conducted for 120 min before localised ischaemia (45 min) and reperfusion (60 min) was performed using a coronary snare. Metabolic and injury markers were collected by microdialysis sampling in the ventricular wall. Recovery of radio-marked calcium delivered locally by microperfusate was measured to assess carbon monoxide treatment effects during ischaemia/reperfusion on the intracellular calcium pool.Coronary occlusion and ischaemia/reperfusion were analysed for 16 animals (eight in each group). Changes in glucose, lactate and pyruvate from the ischaemic area were observed during ischaemia and reperfusion interventions, though there was no difference between carbon monoxide-treated and control groups during ischaemia or reperfusion. Similar results were observed for glycerol and microdialysate Ca recovery.These findings show that a relatively low and clinically relevant dose of carbon monoxide did not seem to provide acute protection as indicated by metabolic, energy-related and injury markers in a porcine myocardial ischaemia/reperfusion experimental model. We conclude that protective effects of carbon monoxide related to ischaemia/reperfusion either require higher doses of carbon monoxide or occur later after reperfusion than the immediate time frame studied here. More study is needed to characterise the mechanism and time frame of carbon monoxide-related cytoprotection.

  • 7.
    Ahlström, Katarina
    et al.
    Anestesi, Sahlgrenska akademin, Göteborgs universitet.
    Biber, Björn
    Anestesi, Sahlgrenska akademin, Göteborgs universitet.
    Åberg, Annamaja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Waldenström, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Ronquist, Gunnar
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Strandén, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Metabolic responses in ischemic myocardium after inhalation of carbon monoxide2009Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 53, nr 8, s. 1036-1042Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: To clarify the mechanisms of carbon monoxide (CO) tissue-protective effects, we studied energy metabolism in an animal model of acute coronary occlusion and pre-treatment with CO. METHODS: In anesthetized pigs, a coronary snare and microdialysis probes were placed. CO (carboxyhemoglobin 5%) was inhaled for 200 min in test animals, followed by 40 min of coronary occlusion. Microdialysate was analyzed for lactate and glucose, and myocardial tissue samples were analyzed for adenosine tri-phosphate, adenosine di-phosphate, and adenosine mono-phosphate. RESULTS: Lactate during coronary occlusion was approximately half as high in CO pre-treated animals and glucose levels decreased to a much lesser degree during ischemia. Energy charge was no different between groups. CONCLUSIONS: CO in the low-doses tested in this model results in a more favorable energy metabolic condition in that glycolysis is decreased in spite of maintained energy charge. Further work is warranted to clarify the possible mechanistic role of energy metabolism for CO protection.

  • 8. Anderson, M
    et al.
    Domellöf, L
    Eksborg, S
    Häggmark, S
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, G
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Reiz, S
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Herslöf, Å
    Pharmacokinetics and Central Haemodynamic Effects of Doxorubicin and 4'Epi-Doxorubicin in the Pig1989Ingår i: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 28, nr 5, s. 709-714Artikel i tidskrift (Refereegranskat)
  • 9.
    Andersson, Magnus
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Domellöf, Lennart
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Reiz, Sebastian
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gustavsson, Bengt
    Cardiopulmonary hemodynamics and pharmacokinetics after hepatic intraarterial infusion of 5-fluorouracil (5-FU)1988Ingår i: Cancer Chemotherapy and Pharmacology, ISSN 0344-5704, E-ISSN 1432-0843, Vol. 22, nr 3, s. 251-255Artikel i tidskrift (Refereegranskat)
  • 10.
    Andersson-Wenckert, Ingrid
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Lindkvist, Robert
    Reiz, Sebastian
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Anevac-D, a new system for close scavenging of anesthetic gases in dental practice1989Ingår i: Scandinavian Journal of Dental Research, ISSN 0029-845X, Vol. 97, nr 5, s. 456-64Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Anevac-D, a new system for close scavenging of anesthetic gases in dental practice is described. It consists of a rubber nose mask surrounded by an outer rigid shell and a chin scavenger. A vacuum in the slot between the nose masks provides scavenging of gases escaping from the inner mask. Gases escaping from the mouth are evacuated mainly by the skin scavenger. The efficiency of this system was assessed in healthy volunteers using argon as a tracer gas. Mass spectrometry was used for measurement of inspired, expired, and scavenged gas concentrations. The scavenging efficiency of the complete system was around 80% and was not affected by poor patient cooperation. It decreased to about 65% when the chin scavenger was removed. The dentist's exposure was measured by sampling of argon in the breathing zone by a Saran system. The average 4-min exposure varied between 90 and 250 ppm depending on system configuration and patient cooperation. Patient acceptance and clinical applicability were judged good. It is concluded that the Anevac-D system provides excellent scavenging properties and exposure levels well within the official recommendations by the Swedish Board of Occupational Safety and Health.

  • 11.
    A'Roch, Roman
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gustafsson, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Poelaert, Jan
    Anesthesiology, University of Brussels, Belgium.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Left ventricular strain and peak systolic velocity: responses to controlled changes in load and contractility, explored in a porcine model2012Ingår i: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 10, nr 22Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Tissue velocity echocardiography is increasingly used to evaluate global and regional cardiac function. Previous studies have suggested that the quantitative measurements obtained during ejection are reliable indices of contractility, though their load-sensitivity has been studied in different settings, but still remains a matter of controversy. We sought to characterize the effects of acute load change (both preload and afterload) and change in inotropic state on peak systolic velocity and strain as a measure of LV contractility.

    METHODS: Thirteen anesthetized juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and transthoracic echocardiography. Transient inflation of a vena cava balloon catheter produced controlled load alterations. At least eight consecutive beats in the sequence were analyzed with tissue velocity echocardiography during the load alteration and analyzed for change in peak systolic velocities and strain during same contractile status with a controlled load alteration. Two pharmacological inotropic interventions were also included to generate several myocardial contractile conditions in each animal.

    RESULTS: Peak systolic velocities reflected the drug-induced changes in contractility in both radial and longitudinal axis. During the acute load change, the peak systolic velocities remain stable when derived from signal in the longitudinal axis and from the radial axis. The peak systolic velocity parameter demonstrated no strong relation to either load or inotropic intervention, that is, it remained unchanged when load was systematically and progressively varied (peak systolic velocity, longitudinal axis, control group beat 1- 5.72 +/- 1.36 with beat 8- 6.49 +/- 1.28 cm/sec, 95% confidence interval), with the single exception of the negative inotropic intervention group where peak systolic velocity decreased a small amount during load reduction (beat 1- 3.98 +/- 0.92 with beat 8- 2.72 +/- 0.89 cm/sec). Systolic strain, however, showed a clear degree of load-dependence.

    CONCLUSIONS: Peak systolic velocity appears to be load-independent as tested by beat-to-beat load reduction, while peak systolic strain appears to be load-dependent in this model. Peak systolic velocity, in a controlled experimental model where successive beats during load alteration are assessed, has a strong relation to contractility. Peak systolic velocity, but not peak strain rate, is largely independent of load, in this model. More study is needed to confirm this finding in the clinical setting.

  • 12.
    A'roch, Roman
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gustafsson, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Poelaert, Jan
    Dept of Anesthesiology and Perioperative Medicine, University hospital of Brussels. Belgium.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Strain and peak systolic velocities: relation to load in a porcine modelManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Background:  Tissue velocity echocardiography is increasingly used to evaluate global and regional cardiac function.  Previous studies have suggested that the quantitative measurements obtained during ejection are reliable indices of contractility.  Their load-sensitivity has been studied in different settings, but still remains a matter of controversy.  We sought to characterize the effects of acute load change and change in inotropic state on peak systolic velocity and strain as a measure of LV contractility, and particularly to determine if these parameters were load-dependent.

    Methods: Thirteen anesthetised juvenile pigs were studied, using direct measurement of left ventricular (LV) pressure and volume and transthoracic echocardiography. Transient inflation of a vena cava balloon catheter produced controlled preload alterations.  At least eight consecutive beats in the preload alteration sequence were analysed with tissue velocity echocardiography (TVE) during the preload alteration and analysed for change in peak systolic velocities (PSV) and strain (e) during same contractile status with a controlled preload alteration.  Two pharmacological inotropic interventions were also included to generate several myocardial contractile conditions in each animal.

    Results: PSV reflected the drug-induced changes in contractility in both radial and longitudinal axis.  During the acute load change, the PSV remain stable when derived from signal in the longitudinal axis and from the radial axis.  The peak systolic velocity parameter demonstrated no strong relation to either load or inotropic intervention, that is, it remained unchanged when load was systematically and progressively varied.  Peak systolic strain, however, showed a clear degree of load-dependence.

    Conclusion:  Peak systolic velocity appears to be load-independent as tested by beat to beat load reduction, while peak systolic strain appears to be load-dependent in this model.  Peak systolic velocity has a strong relation to contractility, independent of load, in serial measures, in this model.  More study is needed to confirm this in the clinical setting.

  • 13.
    A'roch, Roman
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gustafsson, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Poelaert, Jan
    Dept of Anesthesiology and Perioperative Medicine, University hospital of Brussels. Belgium.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Left ventricular twist is load-dependentManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Background: Left ventricular rotation and twist can be assessed noninvasively by speckle tracking echocardiography. We sought to characterize the effects of acute load change and change in inotropic state on rotation parameters as a measure of LV contractility.

    Methods: Seven anesthetised juvenile pigs were studied, using direct measurement of left ventricular (LV) pressure and volume and simultaneous transthoracic echocardiography. Transient inflation of an inferior vena cava balloon catheter (IVCBO) produced controlled load reduction.  First and last beats in the sequence of eight were analysed with speckle tracking (STE) during the load alteration and analysed for change in rotation/twist during controlled load alteration at same contractile status.  Two pharmacological inotropic interventions were also included to examine the same hypothesis in additionally conditions of increased and decreased myocardial contractility in each animal.

    Results: The IVCBO load change compared for first to last beat resulted in LV twist increase (11.67° ±2.65° vs. 16.17° ±3.56° respectively, p < 0.004) during the load alteration and under adrenaline stimulation LV twist increase 12.56° ±5.1° vs. 16.57° ±4.6° (p < 0.013), and though increased, didn’t reach significance in nega­tive inotropic condition.  Untwisting rate increased significantly at baseline from    -41.7°/sec ±41.6°/sec vs. -122.6°/sec ±55.8°/sec (P < 0.039) and under adrenaline stimulation untwisting rate increased  (-55.3°/sec ±3.8°/sec vs.  -111.4°/sec ±24.0°/sec (p<0.05), but did not systematically changed in negative inotropic condition.

    Conclusions: Peak systolic LV twist and peak early diastolic untwisting rate are load dependent.  Changes in LV load should be considered when interpreting  LV rotation/ twist.

  • 14.
    A'Roch, Roman
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gustafsson, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Poelaert, Jan
    Anesthesiology, University of Brussels, Belgium.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Left ventricular twist is load-dependent as shown in a large animal model with controlled cardiac load2012Ingår i: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 10, nr 26Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Left ventricular rotation and twist can be assessed noninvasively by speckle tracking echocardiography. We sought to characterize the effects of acute load change and change in inotropic state on rotation parameters as a measure of left ventricular (LV) contractility.

    METHODS: Seven anesthetised juvenile pigs were studied, using direct measurement of left ventricular pressure and volume and simultaneous transthoracic echocardiography. Transient inflation of an inferior vena cava balloon (IVCB) catheter produced controlled load reduction. First and last beats in the sequence of eight were analysed with speckle tracking (STE) during the load alteration and analysed for change in rotation/twist during controlled load alteration at same contractile status. Two pharmacological inotropic interventions were also included to examine the same hypothesis in additionally conditions of increased and decreased myocardial contractility in each animal. Paired comparisons were made for different load states using the Wilcoxon's Signed Rank test.

    RESULTS: The inferior vena cava balloon occlusion (IVCBO) load change compared for first to last beat resulted in LV twist increase (11.67degrees +/-2.65degrees vs. 16.17degrees +/-3.56degrees respectively, p < 0.004) during the load alteration and under adrenaline stimulation LV twist increase 12.56degrees +/-5.1degrees vs. 16.57degrees +/-4.6degrees (p < 0.013), and though increased, didn't reach significance in negative inotropic condition. Untwisting rate increased significantly at baseline from 41.7degrees/s +/-41.6degrees/s vs.122.6degrees/s +/-55.8degrees/s (P < 0.039) and under adrenaline stimulation untwisting rate increased (55.3degrees/s +/-3.8degrees/s vs.111.4degrees/s +/-24.0degrees/s (p < 0.05), but did not systematically changed in negative inotropic condition.

    CONCLUSIONS: Peak systolic LV twist and peak early diastolic untwisting rate are load dependent. Differences in LV load should be included in the interpretation when serial measures of twist are compared.

  • 15.
    A'Roch, Roman
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Steendijk, Paul
    Oldner, Anders
    Weitzberg, Eddie
    Konrad, David
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Left ventricular mechanical dyssynchrony is load independent at rest and during endotoxaemia in a porcine model2009Ingår i: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 196, nr 4, s. 375-383Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    AIM: In diseased or injured states, the left ventricle displays higher degrees of mechanical dyssynchrony. We aimed at assessing mechanical dyssynchrony ranges in health related to variation in load as well as during acute endotoxin-induced ventricular injury.

    METHODS: In 16 juvenile anaesthetized pigs, a five-segment conductance catheter was placed in the left ventricle as well as a balloon-tipped catheter in the inferior vena cava. Mechanical dyssynchrony during systole, including dyssynchrony time in per cent during systole and internal flow fraction during systole, were measured at rest and during controlled pre-load reduction sequences, as well as during 3 h of endotoxin infusion (0.25 microg kg(-)1 h(-1)).

    RESULTS: Systolic dyssynchrony and internal flow fraction did not change during the course of acute beat-to-beat pre-load alteration. Endotoxin-produced acute pulmonary hypertension by left ventricular dyssynchrony measures was not changed during the early peak of pulmonary hypertension. Endotoxin ventricular injury led to progressive increases in systolic mechanical segmental dyssynchrony (7.9 +/- 1.2-13.0 +/- 1.3%) and ventricular systolic internal flow fraction (7.1 +/- 2.4-16.6 +/- 2.8%), respectively for baseline and then at hour 3. There was no localization of dyssynchrony changes to segment or region in the ventricular long axis during endotoxin infusion.

    CONCLUSION: These results suggest that systolic mechanical dyssynchrony measures may be load independent in health and during acute global ventricular injury by endotoxin. More study is needed to validate ranges in health and disease for parameters of mechanical dyssynchrony.

  • 16.
    Axelsson, Birger
    et al.
    Örebro University, Örebro, Sweden .
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Svenmarker, Staffan
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gupta, Anil
    Örebro University, Örebro, Sweden .
    Tyden, Hans
    Örebro University, Örebro, Sweden .
    Wouters, Patrick
    Ghent, Belgium.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Effects of Combined Milrinone and Levosimendan Treatment on Systolic and Diastolic Function During Postischemic Myocardial Dysfunction in a Porcine Model2016Ingår i: Journal of Cardiovascular Pharmacology and Therapeutics, ISSN 1074-2484, E-ISSN 1940-4034, Vol. 21, nr 5, s. 495-503Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is not known whether there are positive or negative interactions on ventricular function when a calcium-sensitizing inotrope is added to a phosphodiesterase inhibitor in the clinical setting of acute left ventricular (LV) dysfunction. We hypothesized that when levosimendan is added to milrinone treatment, there will be synergetic inotropic and lusitropic effects. This was tested in an anesthetized porcine postischemic global LV injury model, where ventricular pressures and volumes (conductance volumetry) were measured. A global ischemic injury was induced by repetitive left main stem coronary artery occlusions. Load-independent indices of LV function were assessed before and after ventricular injury, after milrinone treatment, and finally after addition of levosimendan to the milrinone treatment. Nonparametric, within-group comparisons were made. The protocol was completed in 12 pigs, 7 of which received the inotrope treatment and 5 of which served as controls. Milrinone led to positive lusitropic effects seen by improvement in tau after myocardial stunning. The addition of levosimendan to milrinone further increased lusitropic state. The latter effect could however not be attributed solely to levosimendan, since lusitropic state also improved spontaneously in time-matched controls at the same rate during the corresponding period. When levosimendan was added to milrinone infusion, there was no increase in systolic function (preload recruitable stroke work) compared to milrinone treatment alone. We conclude that in this model of postischemic LV dysfunction, there appears to be no clear improvement in systolic or diastolic function after addition of levosimendan to established milrinone treatment but also no negative effects of levosimendan in this context.

  • 17.
    Axelsson, Birger
    et al.
    Dept of Cardiovascular and Thoracic Surgery and Anesthesiology and Intensive Care, Örebro University Hospital.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Svenmarker, Staffan
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gupta, Anil
    Dept of Clinical Medicine, School of Health and Medical Sciences, Örebro University.
    Tydén, Hans
    Dept of Clinical Medicine, School of Health and Medical Sciences, Örebro University.
    Wouters, Patrick
    Dept of Anesthesiology, University Hospital Ghent, Ghent, Belgium.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Systolic and diastolic effects of milrinone and levosimendan in porcine post-ischemic myocardial dysfunctionManuskript (preprint) (Övrigt vetenskapligt)
  • 18.
    Axelsson, Birger
    et al.
    Dept of Cardiovascular and Thoracic Surgery, Örebro University hospital.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Gupta, Anil
    Dept of Anesthesiology and Intensive Care, Örebro University hospital.
    Tydén, Hans
    Dept of Cardiovascular and Thoracic Surgery, Örebro University hospital.
    Wouters, Patrick
    Dept of Anesthesiology, University hospital Ghent, Belgium.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Milrinone and levosimendan during porcine myocardial ischemia: no effects on calcium overload and metabolism2013Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 57, nr 6, s. 719-728Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Although inotropic stimulation is considered harmful in the presence of myocardial ischaemia, both calcium sensitisers and phosphodiesterase inhibitors may offer cardioprotection. We hypothesise that these cardioprotective effects are related to an acute alteration of myocardial metabolism. We studied in vivo effects of milrinone and levosimendan on calcium overload and ischaemic markers using left ventricular microdialysis in pigs with acute myocardial ischaemia.

    METHODS: Anaesthetised juvenile pigs, average weight 36 kg, were randomised to one of three intravenous treatment groups: milrinone 50 μg/kg bolus plus infusion 0.5 μg/kg/min (n = 7), levosimendan 24 μg/kg plus infusion 0.2 μg/kg/min (n = 7), or placebo (n = 6) for 60 min prior to and during a 45 min acute regional coronary occlusion. Systemic and myocardial haemodynamics were assessed, and microdialysis was performed with catheters positioned in the left ventricular wall. (45) Ca(2+) was included in the microperfusate in order to assess local calcium uptake into myocardial cells. The microdialysate was analysed for glucose, lactate, pyruvate, glycerol, and for (45) Ca(2+) recovery.

    RESULTS: During ischaemia, there were no differences in microdialysate-measured parameters between control animals and milrinone- or levosimendan-treated groups. In the pre-ischaemic period, arterial blood pressure decreased in all groups while myocardial oxygen consumption remained stable.

    CONCLUSIONS: These findings reject the hypothesis of an immediate energy-conserving effect of milrinone and levosimendan during acute myocardial ischaemia. On the other hand, the data show that inotropic support with milrinone and levosimendan does not worsen the metabolic parameters that were measured in the ischaemic myocardium.

  • 19. Blind, P. -J
    et al.
    Kral, Josef
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Wang, Wanzhong
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk biovetenskap, Patologi.
    Kralova, Ivana
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Microdialysis in early detection of temporary pancreatic ischemia in a porcine model2012Ingår i: European Surgical Research, ISSN 0014-312X, E-ISSN 1421-9921, Vol. 49, nr 3-4, s. 113-120Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Ischemic injury to the pancreas occurs in various clinical conditions. A method for online monitoring of pathophysiological events in pancreatic parenchyma is missing. Aims: To assess the timing of microdialysis (MD) technique response on temporary changes in pancreatic perfusion, and to evaluate the relationship between MD data and systemic markers of anaerobic metabolism and inflammation. Methods: In anaesthetized normoventilated pigs, MD probes were placed in right (control) and left (ischemic) pancreatic lobes, respectively. Following the clamping of the vessels, ischemia was verified by tissue oxygen tension (PtiO2) measurements. Results: PtiO2 decreased within 20 min after the clamping of the vessels, already returning to baseline levels at the first sampling point after the removal of the clamp. MD lactate levels increased, whereas pyruvate and glucose levels decreased at 20 min after the induction of ischemia. These trends continued until the end of ischemia and returned to baseline following reperfusion. Serum lactate, amylase and tumor necrosis factor-alpha levels decreased throughout the protocol time. Conclusion: MD data were in concordance with changes in PtiO2, which is indicative of local anaerobic metabolism. MD allowed the detection of pathophysiological processes within the ischemic pancreas at a stage when no elevations of systemic markers of ischemia or inflammation were observed.

  • 20.
    Broomé, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åneman, Anders
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Acute effects of angiotensin II on myocardial performance2001Ingår i: Acta Anaesthesiol Scand, Vol. 45, nr 9, s. 1147-54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Specific angiotensin II (Ang II) receptors exist in many organs including peripheral blood vessels, cardiac myocytes and the central nervous system. This suggests multiple sites of actions for Ang II throughout the cardiovascular system. Cardiac effects of Ang II are not completely understood, though its prominent vasoconstrictor actions are well described. This study was designed to assess left ventricular function during administration of Ang II using relatively load-independent methods in a whole-animal model. METHODS: Ang II was infused in incremental doses (0-200 microg x h(-1)) in anaesthetised instrumented pigs (n=10). Cardiac systolic and diastolic function were evaluated by analysis of the left ventricular pressure-volume relationship. RESULTS: Heart rate (HR), mean arterial pressure (MAP) and systemic vascular resistance (SVR) increased dose-dependently with Ang II, while cardiac output (CO) remained unchanged. Systolic function indices, end-systolic elastance (Ees) and preload recruitable stroke work (PRSW), demonstrated dose-dependent increases. The diastolic function parameter tau (tau) did not change with increasing Ang II dose. CONCLUSION: Ang II infusion caused increases in contractility indices in anaesthetised pigs in the doses used in this study. The mechanisms for these systolic function effects may be a direct myocardial effect or modulated through changes in autonomic nervous system activity.

  • 21.
    Broomé, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åneman, Anders
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Pressure-independent cardiac effects of angiotensin II in pigs.2004Ingår i: Acta Physiologica Scandinavica, ISSN 0001-6772, Vol. 182, nr 2, s. 111-9Artikel i tidskrift (Refereegranskat)
  • 22.
    Broomé, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Österlund, Barbro
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    The cardiac effects of intracoronary angiotensin II infusion2002Ingår i: Anesth Analg, Vol. 94, nr 4, s. 787-93, table of contentsArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    Angiotensin II (Ang II) is a potent vasoconstrictor, which recently has been shown to also have significant inotropic effects. Previous results regarding the mechanisms of the acute inotropic effects of Ang II are not conclusive. We designed this study to investigate the local cardiac effects of intracoronary Ang II infusion in doses not affecting systemic circulation. Ang II (2.5-40 microg/h) was infused in the left coronary artery of Yorkshire pigs (n = 9) reaching calculated intracoronary Ang II concentrations of 842 +/- 310, 3342 +/- 1238, and 12448 +/- 4393 pg/mL, respectively. Cardiac systolic and diastolic function was evaluated by analysis of the left ventricular pressure-volume relationship. Coronary flow was measured by using a coronary sinus catheter and the retrograde thermodilution technique. No significant changes were seen in the systolic and diastolic function variables of heart rate, end-systolic elastance, preload recruitable stroke work, the time constant for isovolumetric relaxation, or in coronary vascular resistance and flow. The positive inotropic and chronotropic effects of Ang II seen in previous studies seem thus to be mediated via extracardiac actions of Ang II. Coronary vascular tone is not affected by local Ang II infusion in anesthetized pigs. IMPLICATIONS: The positive inotropic and chronotropic effects of angiotension II (Ang II) seen in previous studies seem to be mediated via extracardiac actions of Ang II. Coronary vascular tone is not affected by local Ang II infusion in anesthetized pigs.

  • 23.
    Broomé, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åneman, Anders
    Haney, Michael
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Angiotensin II mesenteric and renal vasoregulation: dissimilar modulatory effects with nitroprusside2000Ingår i: Acta Anaesthesiol Scand, Vol. 44, nr 10, s. 1238-45Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: The role of systemic arterial pressure for the vascular effects of angiotensin II (Ang II) and the interactions between Ang II and perfusion pressure-dependent local vascular control mechanisms are not well understood. This study addresses these aspects of exogenous Ang II in the mesenteric and renal regional circulations. METHODS: Ang II was infused in incremental doses (0-200 microg/h) in anesthetized instrumented pigs (n=10). Renal and portal blood flows were measured by perivascular ultrasound. In the second part of the study, sodium nitroprusside (SNP) was infused at doses titrated to keep mean arterial pressure constant, in spite of concurrent Ang II administration. RESULTS: Powerful dose-dependent vasoconstrictions by Ang II were found in renal and mesenteric vascular beds (at highest Ang II doses vascular resistances increased by 109% and 88% respectively). Ang II-induced vasoconstriction was fully inhibited in the mesenteric, but not in the renal circulation, during conditions of constant mean arterial pressures achieved by SNP infusion. CONCLUSIONS: Mesenteric, but not renal, vasoconstriction by Ang II was inhibited by pharmacological maintenance of perfusion pressure. This could reflect differences between these vascular beds as regards the importance of co-acting myogenic pressure-dependent vasoconstriction. Alternatively, as the drug chosen for pressure control, sodium nitroprusside, serves as a nitric oxide donor, the relative balance between nitric oxide-mediated vasodilation and Ang II-induced vasoconstriction could have regional differences.

  • 24.
    Broomé, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åneman, Anders
    Lehtipalo, Stefan
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Arnerlöv, Conny
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Kirurgi.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Splanchnic vasoconstriction by angiotensin II is arterial pressure dependent2002Ingår i: Acta Anaesthesiol Scand, Vol. 46, nr 1, s. 57-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Our hypothesis was that splanchnic vasoconstriction by exogenous angiotensin II (Ang II) is significantly potentiated by local mechanisms increasing vasomotor tone and that splanchnic tissue oxygenation during administration of Ang II is perfusion pressure dependent. The aim was to study local splanchnic circulatory effects and tissue oxygenation during intravenous infusion of Ang II at different levels of regional arterial driving pressure in a whole-body large animal model. METHODS: Ang II was infused in incremental doses (0-200 microg x h-1) in anaesthetised instrumented pigs (n=8). Mean superior mesenteric arterial pressure (PSMA) was adjusted by a local variable perivascular occluder. Perivascular ultrasound and laser-Doppler flowmetry were used for measurements of mesenteric venous blood flow and superficial intestinal blood flow, respectively. Intestinal oxygenation was evaluated by oxygen tissue tension (PtiO2) and lactate fluxes. RESULTS: Ang II produced prominent and dose-dependent increases in mesenteric vascular resistance (RSMA) when the intestine was exposed to systemic arterial pressure, but Ang II increased RSMA only minimally when PSMA was artificially kept constant at a lower level (50 mmHg) by the occluder. Although Ang II decreased PtiO2 at a PSMA of 50 mmHg, splanchnic lactate production was not observed. CONCLUSION: We demonstrate that splanchnic vasoconstriction by exogenous Ang II is dependent on arterial driving pressure, suggesting significant potentiation through autoregulatory increases in vasomotor tone. Intestinal hypoxaemia does not seem to occur during short-term infusion of Ang II in doses that significantly increases systemic arterial pressure.

  • 25.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Giesbrecht, Gordon G.
    Kinesiology and Recreation Management, and Anesthesia, University of Manitoba, Winnipeg, Canada.
    Ängquist, Karl-Axel
    Emergency and Disaster Medical Center, Umeå University Hospital, Sweden.
    Haney, Michael F.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Accidental cold-related injury leading to hospitalization in northern Sweden: an eight-year retrospective analysis2014Ingår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, ISSN 1757-7241, E-ISSN 1757-7241, Vol. 22, s. 6-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Cold injuries are rare but important causes of hospitalization. We aimed to identify the magnitude of cold injury hospitalization, and assess causes, associated factors and treatment routines in a subarctic region. Methods: In this retrospective analysis of hospital records from the 4 northernmost counties in Sweden, cases from 2000-2007 were identified from the hospital registry by diagnosis codes for accidental hypothermia, frostbite, and cold-water drowning.Results were analyzed for pre-hospital site events, clinical events in-hospital, and complications observed with mild (temperature 34.9 - 32 degrees C), moderate (31.9 - 28 degrees C) and severe (<28 degrees C), hypothermia as well as for frostbite and cold-water drowning. Results: From the 362 cases, average annual incidences for hypothermia, frostbite, and cold-water drowning were estimated to be 3.4/100 000, 1.5/100 000, and 0.8/100 000 inhabitants, respectively. Annual frequencies for hypothermia hospitalizations increased by approximately 3 cases/year during the study period. Twenty percent of the hypothermia cases were mild, 40% moderate, and 24% severe. For 12%, the lowest documented core temperature was 35 degrees C or higher, for 4% there was no temperature documented. Body core temperature was seldom measured in pre-hospital locations. Of 362 cold injury admissions, 17 (5%) died in hospital related to their injuries. Associated co-factors and co-morbidities included ethanol consumption, dementia, and psychiatric diagnosis. Conclusions: The incidence of accidental hypothermia seems to be increasing in this studied sub-arctic region. Likely associated factors are recognized (ethanol intake, dementia, and psychiatric diagnosis).

  • 26.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Sundelin, Anna
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Hoseason, Daniela
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Sundström, Nina
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Koskinen, Lars-Owe
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Risk for intracranial pressure increase related to enclosed air in post-craniotomy patients during air ambulance transport: a retrospective cohort study with simulation2017Ingår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, ISSN 1757-7241, E-ISSN 1757-7241, Vol. 25, artikel-id 50Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Post-craniotomy intracranial air can be present in patients scheduled for air ambulance transport to their home hospital. We aimed to assess risk for in-flight intracranial pressure (ICP) increases related to observed intracranial air volumes, hypothetical sea level pre-transport ICP, and different potential flight levels and cabin pressures. METHODS: A cohort of consecutive subdural hematoma evacuation patients from one University Medical Centre was assessed with post-operative intracranial air volume measurements by computed tomography. Intracranial pressure changes related to estimated intracranial air volume effects of changing atmospheric pressure (simulating flight and cabin pressure changes up to 8000 ft) were simulated using an established model for intracranial pressure and volume relations. RESULTS: Approximately one third of the cohort had post-operative intracranial air. Of these, approximately one third had intracranial air volumes less than 11 ml. The simulation estimated that the expected changes in intracranial pressure during 'flight' would not result in intracranial hypertension. For intracranial air volumes above 11 ml, the simulation suggested that it was possible that intracranial hypertension could develop 'inflight' related to cabin pressure drop. Depending on the pre-flight intracranial pressure and air volume, this could occur quite early during the assent phase in the flight profile. DISCUSSION: These findings support the idea that there should be radiographic verification of the presence or absence of intracranial air after craniotomy for patients planned for long distance air transport. CONCLUSIONS: Very small amounts of air are clinically inconsequential. Otherwise, air transport with maintained ground-level cabin pressure should be a priority for these patients.

  • 27.
    Claesson, Jonas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård. Anestesiologi och intensivvård.
    Lehtipalo, Stefan
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård. Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård. Anestesiologi och intensivvård.
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård. Anestesiologi och intensivvård.
    Palmqvist, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk biovetenskap, Patologi.
    Biber, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård. Anestesiologi och intensivvård.
    Evaluation of intestinal preconditioning in a porcine model using classic ischemic preconditioning or lung recruitment maneuvers.2008Ingår i: Shock, ISSN 1073-2322, E-ISSN 1540-0514, Vol. 21, nr 1, s. 98-103Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To test the hypotheses that repeated brief intestinal ischemic insults would elicit an intestinal preconditioning response to a subsequent intestinal I/R injury and that a similar response would be elicited by repeated lung recruitment maneuvers (RMs). Randomized experimental controlled animal study. University hospital animal laboratory. Eighteen anesthetized pigs. Animals were randomized to one of three groups, with six animals in each group. Control group 75-min superior mesenteric artery (SMA) occlusion followed by 60-min reperfusion. Ischemic preconditioning group, three 5-min-long SMA occlusions preceding 75-min SMA occlusion and 60-min reperfusion. Recruitment maneuver (RM) group, three 2-min-long RMs preceding 75-min SMA occlusion and 60-min reperfusion. We measured systemic and mesenteric hemodynamic parameters, jejunal mucosal perfusion, net mesenteric lactate flux, jejunal tissue oxygen tension, and mesenteric oxygenation. Every 15 min, jejunal microdialysate samples were collected and analyzed for glucose, lactate, and glycerol. Jejunal tissue samples were collected postmortem. After occlusion of SMA, regional parameters in all groups indicated abolished perfusion and gradually increasing intraluminal microdialysate lactate and glycerol levels. At reperfusion, regional parameters indicated mesenteric hyperperfusion, whereas microdialysis markers of mucosal anaerobic metabolism and cell injury decreased, although not reaching baseline. Histological examination revealed severe mucosal injury in all groups. There were no significant differences between groups in the observed parameters. No protective preconditioning response could be observed when performing repeated brief intestinal ischemic insults or repeated lung RMs before an intestinal I/R injury.

  • 28.
    Franklin, Karl
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Lungmedicin.
    Sandström, Erik
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Bålfors, Eva
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Hemodynamics, cerebral circulation, and oxygen saturation in Cheyne-Stokes respiration1997Ingår i: J Appl Physiol, Vol. 83, nr 4, s. 1184-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Because cardiovascular disorders and stroke may induce Cheyne-Stokes respiration, our purpose was to study the interaction among cerebral activity, cerebral circulation, blood pressure, and blood gases during Cheyne-Stokes respiration. Ten patients with heart failure or a previous stroke were investigated during Cheyne-Stokes respiration with recordings of daytime polysomnography, cerebral blood flow velocity, intra-arterial blood pressure, and intra-arterial oxygen saturation with and without oxygen administration. There were simultaneous changes in wakefulness, cerebral blood flow velocity, and respiration with accompanying changes in blood pressure and heart rate approximately 10 s later. Cerebral blood flow velocity, blood pressure, and heart rate had a minimum occurrence in apnea and a maximum occurrence during hyperpnea. The apnea-induced oxygen desaturations were diminished during oxygen administration, but the hemodynamic alterations persisted. Oxygen desaturations were more severe and occurred earlier according to intra-arterial measurements than with finger oximetry. It is not possible to explain Cheyne-Stokes respiration by alterations in blood gases and circulatory time alone. Cheyne-Stokes respiration may be characterized as a state of phase-linked cyclic changes in cerebral, respiratory, and cardiovascular functions probably generated by variations in central nervous activity.

  • 29.
    Fröjse, Rolf
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Kirurgi.
    Lehtipalo, Stefan
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Bergstrand, Ulf
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Arnerlöv, Conny
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Kirurgi.
    Local metabolic effects of dopexamine on the intestine during mesenteric hypoperfusion.2004Ingår i: Shock, ISSN 1073-2322, E-ISSN 1540-0514, Vol. 21, nr 3, s. 241-247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This self-controlled experimental study was designed to test the hypothesis that dopexamine, a synthetic catecholamine that activates dopaminergic (DA-1) and beta2-adrenergic receptors, improves oxygenation in the jejunal mucosa during intestinal hypotension. In six normoventilated barbiturate-anesthetized pigs, controlled reductions in superior mesenteric arterial pressure (PSMA) was obtained by an adjustable clamp around the artery. Dopexamine infusions (0.5 and 1.0 microg.kg(-1).min(-1)) were administered at a freely variable PSMA (i.e., with the perivascular clamp fully open) and at a PSMA of 50 mmHg and 30 mmHg. We continuously measured superior mesenteric venous blood flow (QMES; transit-time ultrasonic flowmetry), jejunal mucosal perfusion (laser Doppler flowmetry), and tissue oxygen tension (PO2TISSUE; microoximetry). Jejunal luminal microdialysate of lactate, pyruvate, and glucose were measured every 5 min. Measurements of mucosal PCO2 (air tonometry), together with blood sampling and end-tidal PCO2 measurements, enabled calculations of pHi and PCO2 gap. Dopexamine reduced mesenteric vascular resistance and increased QMES at a PSMA of 50 mmHg and 30 mmHg. At a PSMA of 30 mmHg, dopexamine increased mesenteric oxygen delivery but did not influence mesenteric oxygen uptake or extraction. In this situation, dopexamine had no beneficial effect on jejunal mucosal blood flow. On the contrary, dopexamine increased mesenteric net lactate production and PCO2 gap, whereas PO2TISSUE and pHi decreased. Jejunal luminal microdialysate data demonstrated an increased lactate concentration and a pattern of decreased glucose concentration and increased luminal lactate-pyruvate ratio. These negative metabolic effects of dopexamine should be taken into account in situations of low perfusion pressures.

  • 30.
    Fröjse, Rolf
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Kirurgi.
    Lehtipalo, Stefan
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Arnerlöv, Conny
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Kirurgi.
    Assessment of graded intestinal hypoperfusion and reperfusion using continuous saline tonometry in a porcine model.2004Ingår i: European Journal of Vascular and Endovascular Surgery, ISSN 1078-5884, E-ISSN 1532-2165, Vol. 28, nr 1, s. 79-88Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To evaluate effects of graded intestinal hypoperfusion and reperfusion on intestinal metabolic parameters as assessed by a modified continuous saline tonometry technique. MATERIALS: Twelve barbiturate-anaesthetized female pigs. METHODS: Measurements were performed prior to and during three predefined levels of superior mesenteric mean arterial blood pressure (P(SMA) 70, 50 and 30 mmHg, respectively, each 80 min long), obtained by an adjustable clamp around the origin of the superior mesenteric artery, and during reperfusion. We continuously measured jejunal mucosal perfusion (laser Doppler flowmetry), jejunal tissue oxygen tension (PO(2TISSUE); microoximetry) and intramucosal PCO(2) (continuous saline tonometry) and calculated net intestinal lactate production, mesenteric oxygenation, PCO(2) gap (jejunal mucosal PCO(2)-arterial PCO(2)) and pHi. RESULTS: At P(SMA) 70 and 50 mmHg mesenteric oxygen uptake and net lactate production remained unaltered, in spite of decreased oxygen delivery. At these P(SMA) levels PCO(2) gap increased, while pHi and PO(2TISSUE) decreased. At P(SMA) 30 mmHg pronounced increases in PCO(2) gap and mesenteric net lactate production as well as marked decreases in PO(2TISSUE) and pHi were demonstrated. Data indicate absence of anaerobic conditions at an intestinal perfusion pressure (IPP)> or =41 mmHg, a pHi> or =7.22 or PCO(2) gap< or =15.8 mmHg. CONCLUSIONS: Continuous saline tonometry detected intestinal ischemia as induced by graded reductions in IPP. A threshold could be defined above which intestinal ischemia does not occur.

  • 31.
    Haney, Michael
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    A'Roch, Roman
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Poelaert, Jan
    Biber, Björn
    Beat-to-beat change in myocardial performance index related to load2007Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 51, nr 5, s. 545-552Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: This study was designed to assess the relationship of the "myocardial performance index" (MPI) to the beat-by-beat change in pre-load with static or unchanged contractile status.

    METHODS: Eight anesthetized juvenile pigs were studied using direct measurement of the left ventricular pressure and volume. Transient inflation of a vena cava balloon catheter produced controlled pre-load alterations. Consecutive beats were analyzed, grouped for first, second, third, etc. during the pre-load alteration, and evaluated for the change in MPI during the same contractile status with a controlled pre-load alteration. Two pharmacologic inotropic interventions were also included to generate several myocardial conditions in each animal.

    RESULTS: MPI demonstrated a strong linear relationship to the pre-load and after-load. MPI increased progressively during decreasing end-diastolic volume, mostly related to changes in ejection time. MPI was observed at the same level for three different myocardial function conditions (all eight animals), with a different relationship between MPI and pre-load noted for each observation.

    CONCLUSIONS: MPI is strongly load dependent, and can vary widely in value for the same contractile status if the load is varied. The use of this index in critically ill patients should be limited in this respect. Further work is needed to establish the relationship of MPI to load and contractile status.

  • 32.
    Haney, Michael F
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin. Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    ST changes and temporal relation to the J point during heart rate increase and myocardial ischemia.2009Ingår i: Journal of electrocardiology, ISSN 1532-8430, Vol. 42, nr 1, s. 6-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is no concensus concerning where in the ST segment to measure. We studied the relation between different J point intervals to ST results during tachycardia and ischemia. Symptomatic (anesthetized) patients with coronary artery disease were paced at ascending incremental levels until they became ischemic. ST vector magnitude and ST vector change from baseline (STC-VM) as well as the sum of ST changes from all 12 electrocardiogram (ECG) leads (ECG ST sum) were measured at J point 0 millisecond, J + 20, J + 60, and J + 80 milliseconds for 34 patients. ST segments increased in similar fashion during pacing and ischemia. There was no difference in ST results when measurement was performed at different time intervals for both STC-VM and ECG ST sum. We conclude that ST assessment by ST change from baseline is not affected by different J point intervals during increased heart rate and ischemia in this clinical model of pacing-induced ischemia and vectorcardiographic ST analysis.

  • 33.
    Haney, Michael F
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Myocardial systolic function increases during positive pressure lung inflation.2005Ingår i: Anesthesia and Analgesia, ISSN 0003-2999, Vol. 101, nr 5, s. 1269-74Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Lung inflation with positive airway pressure may have rapid and dynamic effects on myocardial contractile function. We designed this study to assess the magnitude and time to onset of myocardial function changes during the initiation of single positive pressure lung inflation at clinically relevant inflation pressures. In 8 anesthetized 40-kg pigs, left ventricular pressures and volumes were measured directly (conductance volumetry). A 15 cm H2O airway pressure plateau with lung inflation (PPLI-15) was performed, and 2 single beats from that sequence, one from resting apnea at zero airway pressure and the second from the point when the lungs were first maximally inflated, were selected for analysis. Systolic function variables for zero airway pressure and PPLI-15 were analyzed. Systolic elastance, derived from bilinear time-varying elastance curves, increased approximately 15% during PPLI-15 from zero airway pressure. This agreed with other systolic function variables that identified an increase in left ventricular contractile function for the lung inflation beat. Serial measurements of myocardial function should be conducted with constant airway pressure and lung inflation conditions.

  • 34.
    Haney, Michael F
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Steendijk, Paul
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    The effect of lung inflation on absolute ventricular volume measurement by conductance.2006Ingår i: Clin Physiol Funct Imaging, ISSN 1475-0961, Vol. 26, nr 4, s. 220-3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Conductance catheter in vivo ventricular volume measurements during lung ventilation may provide important information on left ventricular (LV) function. Breathing potentially may alter parallel conductance (V(c)), complicating interpretation of the conductance-derived volume signals. The effects of controlled positive pressure lung inflation (PPLI) on measured parallel conductance with dual-field conductance volumetry were investigated. METHODS: Eight anaesthetized pigs were instrumented with an LV dual-field conductance volumetry catheter. V(c) was measured repeatedly, using the hypertonic saline injection method, at three different levels of lung insufflation: continuous positive airway pressure (PPLI) 0, 5, and 10 cm H(2)O. RESULTS: V(c)s measured at PPLI 0, 5 and 10 cm H(2)O were 70.9 +/- 4.8, 70.7 +/- 5.5 and 70.5 +/- 5.9 ml, respectively. The corresponding uncalibrated end-diastolic volumes (EDV(u)) were 115.5 +/- 7.1, 117.0 +/- 7.5 and 117.5 +/- 7.7 ml, respectively. Mean coefficients of variance for V(c) and EDV(u) at all three PPLI levels were 3.8% and 1.25%, respectively. DISCUSSION: Several levels of PPLI demonstrated no systematic change in parallel conductance for LV dual-field conductance volume signal. We concluded that lung inflation at these levels does not generate changes in V(c).

  • 35.
    Haney, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Analysis of left ventricular systolic function during elevated external cardiac pressures: an examination of measured transmural left ventricular pressure during pressure-volume analysis2001Ingår i: Acta Anaesthesiol Scand, Vol. 45, nr 7, s. 868-74Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Variations or disturbances in intrathoracic and extracardiac pressures (ECP) occur in critically ill and anaesthetised patients. There are uncertainties concerning the analysis of left ventricular pressure-volume relationship (LVPVR) and the calculation of systolic function parameters when conducted without reference to transmural left ventricular pressure (LVPtm) in the setting of elevated ECP. METHODS: In 7 anaesthetised adult pigs, we measured LVPVR using conductance volumetry and tip manometry along with measurement of pericardial and other intrathoracic pressures. Experimental pericardial infusion and pleural insufflation were performed. Transient controlled preload reductions were accomplished using balloon occlusion of the inferior vena cava. Preload recruitable stroke work (PRSW) was calculated using both intracavitary left ventricular pressure (LVPic) and LVPtm, and differences were tested for using a paired t-test. RESULTS: The pericardial and pleural interventions produced significant elevations in ECP. No difference in PRSW calculated using LVPic and LVPtm was detected. CONCLUSION: These results suggest that LVPtm need not be measured and included in LVPVR analysis of systolic function when there is significant external cardiac pressure. To be able to employ LVPVR analysis of systolic function without reference to LVPtm is important for simplified application in the clinical setting, particularly when elevated extracardiac pressures are suspected, or have been therapeutically induced, as with continuous positive pressure ventilation.

  • 36.
    Haney, Michael
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Heart-lung interactions during positive pressure ventilation: left ventricular pressure-volume momentary response to airway pressure elevation2001Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 45, nr 6, s. 702-709Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Left ventricular (LV) pressure and volume changes are known to occur in response to positive airway pressure (PAP). We aimed to further describe the immediate LV response to increased PAP as demonstrated in successive heart cycles with LV pressure and volume alterations. We postulated that these acute systematic LV events during institution of PAP can follow a distinct pattern that would allow calculation of parameters of systolic function, including end-systolic elastance (Ees) and preload recruitable stroke work (PRSW). We also aimed to examine the relationship of PAP-derived Ees and PRSW to the same parameters derived from vascular occlusion. METHODS: Eight anesthetized adult pigs were studied with invasive circulatory measurements including LV pressure and volume (conductance). The PAP intervention was an airway pressure plateau of 15 cm H2O for 6 s (APP). Venous occlusion was performed by transient balloon inflation in the inferior vena cava (IVCO). Ees and PRSW were derived for each APP and IVCO intervention. RESULTS: Central circulatory variables during APP and IVCO are reported. LV systolic function parameters could be derived from each of the heart-lung interactions during APP sequences. Ees and PRSW derived from APP showed a significant positive bias in relation to those derived from the IVCO sequence. CONCLUSIONS: We conclude that the heart-lung interactions during APP of the magnitude and duration shown here can allow derivation of Ees and PRSW. These parameters are not interchangeable with Ees and PRSW derived from IVCO.

  • 37.
    Haney, Michael
    et al.
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Häggmark, Sören
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinsk fakultet, Kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Method of preload reduction during LVPVR analysis of systolic function: airway pressure elevation and vena cava occlusion2002Ingår i: Anesthesiology, Vol. 97, nr 2, s. 436-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: A graded preload reduction during analysis of the left ventricular pressure-volume relationship (LVPVR) is required for derivation of end-systolic elastance (Ees) and preload recruitable stroke work (PRSW). The authors aimed to measure serial changes in these systolic function parameters before and during planned circulatory interventions using two different methods of preload alteration: a positive airway pressure plateau (APP) and inferior vena cava occlusion (IVCO). METHODS: In eight animals, measurements were made at 38 degrees, 30 degrees, 32 degrees, 34 degrees, and posthypothermia 38 degrees C. In an additional eight animals, isoflurane, adrenaline, and aorta occlusion (balloon catheter occluder) were administered in series, each with a preintervention control measurement. Left ventricular volume was measured by conductance. Paired measurements of the systolic function parameters Ees and PRSW, each derived with two preload methods, were analyzed for bias. RESULTS: Circulatory alterations were achieved with the temperature, isoflurane, adrenaline, and aorta occlusion interventions. Measured changes in Ees and PRSW from control to intervention showed a strong correlation and no significant bias for APP in relation to IVCO. The APP-derived absolute values for Ees and PRSW demonstrated a consistent positive bias compared with IVCO. CONCLUSION: The APP method for preload reduction during LVPVR analysis detected changes in Ees and PRSW during the circulatory interventions in this model that were not different than those detected using another preload reduction method, IVCO. APP and IVCO are not interchangeable methods for preload reductions during LVPVR absolute quantitation of systolic function, and each needs to be used serially.

  • 38.
    Hohner, P.
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Backman, C.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Klinisk fysiologi.
    Diamond, G.
    Friedman, A.
    Häggmark, S.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, G.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Karp, K.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Klinisk fysiologi.
    Reiz, S.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Anaesthesia for abdominal aortic surgery in patients with coronary artery disease, Part II: Effects of nitrous oxide on systemic and coronary haemodynamics, regional ventricular function and incidence of myocardial ischaemia1994Ingår i: Acta Anaesthesiol Scand, Vol. 38, nr 8, s. 793-804Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study examines the effects of nitrous oxide on haemodynamics, anterior left ventricular (LV) function and incidence of myocardial ischaemia in abdominal vascular surgical patients with coronary artery disease. Forty-seven patients were randomly assigned to isoflurane-fentanyl anaesthesia with nitrous oxide-oxygen vs air-oxygen (control). Systemic and coronary haemodynamics, 12-lead ECG, LV anterior wall motion by cardiokymography (CKG) and myocardial lactate balance were recorded at four intervals: before and during anaesthesia and 10 and 30 minutes into surgery. Systemic haemodynamics were controlled by anaesthetic dose, and, when insufficient, by i.v. nitroglycerine (NG) in case of LV failure (PCWP > 18 mmHg) and by phenylephrine during hypotension. We found that nitrous oxide was associated with greater need for i.v. nitroglycerin (patients: P = 0.031, episodes P = 0.005) and more myocardial ischaemia (patients P = 0.012, episodes P = 0.001) despite systemic and coronary haemodynamics comparable to the control group. We conclude that nitrous oxide, known to have both sympathomimetic and cardiodepressive actions, produced cardiodepression in the face of sympathetic stimulation. Our study design did not allow to conclude if myocardial ischaemia was the consequence of increased wall stress or a reason for the observed LV dysfunction. The higher incidence of introperative myocardial ischaemia and need for NG did not cause increased cardiac morbidity.

  • 39.
    Hohner, Per
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Nancarrow, Craig
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Backman, Clas
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Fridén, Håkan
    Diamond, George
    Friedman, Arnold
    Reiz, Sebastian
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Anaesthesia for abdominal vascular surgery in patients with coronary artery disease (CAD), Part I: Isoflurane produces dose-dependent coronary vasodilation1994Ingår i: Acta Anaesthesiol Scand, Vol. 38, nr 8, s. 780-92Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The effects of anaesthesia for major abdominal vascular surgery on coronary flow regulation and mechanisms of myocardial ischaemia were studied in 56 patients with CAD, using a randomized, partly double-blinded protocol. After induction with fentanyl (3 micrograms.kg-1) and thiopentone (2-4 mg.kg-1) and tracheal intubation, principal anaesthetics were nitrous oxide/oxygen (60/40) with isoflurane (n = 20), halothane (n = 19) or fentanyl (15-20 micrograms.kg-1) (n = 17). Conventional invasive techniques and coronary venous retrograde thermodilution were used to assess systemic and coronary haemodynamics. Coronary vascular resistance was estimated from myocardial oxygen extraction. Myocardial ischaemia was diagnosed by 12-lead ECG and/or anterior wall motion abnormalities by cardiokymography and/or myocardial lactate production. When adjustment of anaesthetic dose was insufficient for haemodynamic control, i.v. phenylephrine and nitroglycerine were administered to treat hypotension and hypertension or cardiac failure respectively. Measurements were performed at four specific intervals; awake, before surgery and 10 and 30 min after abdominal incision. Comparable changes of systemic haemodynamics and myocardial oxygen consumption were observed in the three groups. Coronary vasodilation was evidenced in isoflurane patients only and was linearly dose-dependent (P < 0.001). Partial Least Squares Projections to Latent Structures modelling with cross validation confirmed this dose-dependency and ruled out a clinically measurable influence by intervention drugs or simultaneous systemic haemodynamic abnormalities. The incidence of myocardial ischaemia during anaesthesia and surgery was comparable in the three groups (35, 37 and 24%, respectively) and there was an association with systemic haemodynamic aberrations in 19 of the 27 ischaemic episodes. In contrast to ischaemic halothane and fentanyl patients, isoflurane patients with ischaemia had significantly lower myocardial oxygen extraction (P = 0.008 and P = 0.001, respectively), indicating that the oxygen extraction reserve was not utilized in a normal way during ischaemia.

  • 40.
    Häggmark, Sören
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael F
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Jensen, Steen M
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin.
    ST-segment deviations during pacing-induced increased heart rate in patients without coronary artery disease.2005Ingår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 25, nr 4, s. 246-522Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    INTRODUCTION: In order to interpret ST-segment changes as an indicator of ischemia in patients with higher heart rates (HRs), the relation between ST-segment levels and HR needs to be well defined in subjects without coronary artery disease. METHODS: Eighteen patients with normal ECGs in the catheterization laboratory, after radiofrequency ablation of AV nodal re-entry tachycardia or an accessory pathway were included. Computerized online vectorcardiography (VCG) was performed during step-wise atrial pacing-induced increases in HR up to 150 beats min(-1) (bpm). The ST-vector magnitude (ST-VM) and the relative ST change vector magnitude (STC-VM) were analysed at the J point, J + 20 and J + 60 ms. RESULTS: There was no divergence in the course of ST-VM or STC-VM based on J point + 0, 20, or 60 ms during increasing HR. The STC-VM mean values increased progressively during increases in HR above 100 bpm, with an average increase in STC-VM of 15-20 microV per 10 bpm increases in HR. The ST-VM response during HR increases showed a heterogeneous and unpredictable pattern. CONCLUSION: The STC-VM increases linearly with rising HRs above 100 bpm. The STC-VM can exceed widely recognized ischemic thresholds during higher HRs in the absence of ischemia. The choice of J point time to ST-VM measurements as tested here is not important for the STC-VM relation to HR at these HR levels. Further clinical testing is needed to improve the diagnostic specificity of STC-VM measurements during increased HRs.

  • 41.
    Häggmark, Sören
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael F
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Biber, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin.
    Vectorcardiographic ST deviations related to increased heart rate in the absence of ischemia in an experimental pig model.2006Ingår i: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 39, nr 2, s. 169-176Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The electrocardiographic ST segment may change when heart rate (HR) increases. We aimed to analyze vectorcardiographic ST relation and myocardial conditions during controlled HR increases in anesthetized pigs. The relative parameters ST change vector magnitude and ST change vector angle were calculated at paced HRs ranging from 85 to 175 beats per minute. ST change vector magnitude increased from baseline 6.3 +/- 1.3 to 26.0 +/- 3.1 microV (P < .01; range, 4-50 microV) at HR 175 beats per minute with similar changes in ST change vector angle, whereas the absolute parameter ST vector magnitude demonstrated a heterogeneous pattern without any systematic relation to HR changes. Microdialysis results from left ventricular wall, with analysis of glucose, lactate, and pyruvate, showed no sign of ischemia during pacing. Potassium concentrations did not change during pacing. We conclude that significant HR-related ST vector changes can occur in the absence of myocardial ischemia.

  • 42.
    Häggmark, Sören
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Reiz, Sebastian
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Contributions of myocardial ischemia and heart rate to ST segment changes in patients with or without coronary artery disease.2008Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 52, nr 2, s. 219-228Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: ST changes related to ischemia at different heart rates (HRs) have not been well described. We aimed to analyze ST dynamic changes by vectorcardiography (VCG) during pacing-induced HR changes for subjects with proven coronary artery disease (CAD) and without (non-CAD). METHODS: Symptomatic CAD patients scheduled for elective surgery were enrolled along with a non-CAD group. During anesthesia, both groups were placed at multiple ascending levels. VCG ST data, and in particular in ST change vector magnitude (STC-VM) from baseline, along with arterial and great coronary artery vein (GCV) blood samples were collected to determine regional myocardial lactate production. RESULTS: A total of 35 CAD and 10 non-CAD patients were studied over six incremental 10 beat/min HR increases. STC-VM mean levels increased in the CAD group from 9+/-5 to 131+/-37 microV (standard deviation) compared with non-CAD subjects with 8+/-3-76+/-34 microV. Myocardial ischemia (lactate production) was noted at higher HRs and the positive predictive value for STC-VM to detect ischemia was 58% with the negative predictive value being 88%. STC-VM at 54 microV showed a sensitivity of 88% and a specificity of 75% for identification of ischemia. CONCLUSIONS: Both HR and ischemia at higher HRs contribute to VCG ST elevation. Established ST ischemia detection concerning HR levels is suboptimal, and further attention to the effects of HR on ST segments is needed to improve electrocardiographic ischemia criteria.

  • 43.
    Jacobson, Sofie
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Primary sepsis in a university hospital in northern Sweden: a retrospective study2004Ingår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 48, nr 8, s. 960-967Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: Severe sepsis and septic shock are associated with high mortality rates. Data on sepsis outcome from Scandinavian countries are sparse. The aim of this study was to examine the length of stay (LOS) in the ICU, ICU mortality and costs of care for adult patients with primary sepsis in a university hospital in northern Sweden.

    METHODS: We performed a retrospective data analysis of records of 92 patients admitted over a 3-year period, under the diagnosis of sepsis or urosepsis. Demographic data, admission category, APACHE II score, aetiology and severity of sepsis, ICU LOS, mortality and TISS were analyzed.

    RESULTS: Eighty-one adult patients were identified by standard definitions as suffering from sepsis. The median ICU length of stay was 4.2 days, 6 days for survivors and 2.1 days for non-survivors. Thirteen out of 20 deaths occurred within the first 3 days after admission. Overall ICU mortality rate was 24.7% while the ICU mortality for patients with septic shock was 57.7%. The mean costs of care for patients with sepsis were 3139 Euros day(-1) and the cost of care per patient surviving sepsis was 38,494 Euros.

    CONCLUSION: The incidence of primary sepsis in our ICU was low. Previous reports on high mortality in association with severe sepsis and septic shock are valid also at our hospital. The ICU-LOS was shorter than previously reported, while our costs of care were in the same range as stated by others. This retrospective analysis is valid for interpretation of the applicability of currently available sepsis therapies.

  • 44.
    Jacobson, Sofie
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Larsson, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Idrottsmedicin.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Norberg, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Wadell, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi.
    Hallmans, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Näringsforskning. Umeå universitet, Medicinska fakulteten, Enheten för biobanksforskning.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Söderberg, Stefan
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Leptin independently predicts development of future sepsis and determines survival in the acute phaseManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Objective: To determine if levels of the adipocyte-derived hormones leptin and adiponectin (adipokines) predict sepsis development and if intra-individual changes in circulating levels from baseline to the acute phase affect outcome.

    Method: A nested case-referent study within the framework of the Northern Sweden Health and Disease Study (NSHDS) and the Northern Sweden Maternity Cohort (NSMC). Patients aged 18 years or more with documented sepsis within 24 hours after admission to the intensive care unit (ICU) were included if they had participated in a health survey and donated blood samples prior to the sepsis event, and if possible also had stored plasma from the acute phase. Two matched referents free of known sepsis were selected for each case. Baseline and acute phase plasma leptin and adiponectin levels were determined. The associations between adipokines and sepsis and its severity and outcome were determined.

    Results: We identified 57 men and 97 women with a first-time sepsis event 6.5 years (median with IQR 7.7) after participation in the health survey, and 83% of them had also samples from the acute septic phase. Hyperleptinemia associated with a future sepsis event (OR 1.77, 95% CI 1.04-3.00, P=0.03), with stronger associations with severe sepsis and septic shock than with sepsis. High leptin levels were also associated with hospital death in the fully adjusted model. Leptin remained associated with sepsis in men (P=0.02), but not in women (P=0.36), after stratification and adjustment for BMI. In the acute phase, leptin increased more in men than in women (P=0.001), and high leptin levels were associated with increased risk for in-hospital death in women (OR 4.18, 95%CI 1.17-15.00, P=0.03), while being protective in men (OR 0.05, 95% CI 0.01-0.48, P=0.01). Adiponectin did not associate with sepsis or outcome.

    Conclusions: Hyperleptinemia independently predicted the development of sepsis, and an unfavourable outcome in men. Adiponectin was not associated with sepsis development.

  • 45.
    Jacobson, Sofie
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Liedgren, Eva
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Ferm, Martin
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Sequential organ failure assessment score (SOFA) scores differ between genders in a sepsis cohort: cause or effect?2012Ingår i: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 117, nr 4, s. 415-425Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Controversy exists regarding the influence of gender on sepsis events and out­come. Epidemiological data from other countries may not always apply to local circum­stances.  The aim of this study was to identify gender differences in patient characteristics, treatment and outcome related to the occurrence of sepsis at admission to the ICU.

    Methods: A prospective observational cohort study on patients admitted to the ICU over a three-year period fulfilling sepsis criteria during the first 24 hours. Demographic data, APACHE II score, SOFA score, TISS 76, aetiology, length of stay (LOS), mortality rate and aspects of treatment were collected and then analysed with respect to gender differences.

    Results: There were no gender related differences in mortality or length of stay. Early organ dysfunction assessed as SOFA score at admission was a stronger risk factor for hospital mor­tality for women than for men. This discrepancy was mainly associated with the coagulation sub score. CRP-levels differed between genders in relation to hospital mortality. Infection from the abdominopelvic region was more common among women whereas infection from skin or skin structures were more common in men.

    Conclusion: In this cohort, gender was not associated with increased mortality during a two year follow up period.  SOFA score at ICU-admission was a stronger risk factor for hospital mortality for women than for men. The discrepancy was mainly related to the coagulation SOFA sub score. Together with differences in CRP-levels this may suggest differences in inflammatory response patterns between genders.

  • 46.
    Jacobson, Sofie
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Åberg, Anna-Maja
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Norberg, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Wadell, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi.
    Hallmans, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Näringsforskning. Umeå universitet, Medicinska fakulteten, Enheten för biobanksforskning.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Söderberg, Stefan
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Levels of mannose-binding lectin (MBL) predicts sepsis and associates with sepsis-related in-hospital mortality differentially in men and womenManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Objective: To determine if levels of mannose-binding lectin (MBL) predict sepsis development and if intra-individual changes in circulating levels from baseline to the acute septic phase associate with in-hospital mortality.

    Method: A nested case-referent study within the framework of the Northern Sweden Health and Disease Study (NSHDS) and the Northern Sweden Maternity Cohort (NSMC). Patients aged 18 years or more with documented sepsis within 24 hours after admission to the intensive care unit were included if they had participated in a health survey and donated blood samples prior to the sepsis event. A subset of these patients had stored plasma also from the acute phase. Two matched referents free of known sepsis were selected for each case. Baseline and acute phase plasma MBL levels were determined. The association between MBL and sepsis, sepsis severity and in-hospital mortality were determined.

    Results: We identified 57 men and 95 women with a first-time sepsis event 6.5 years (median with IQR 7.7) after participation in a health survey, of which 127 also had samples from the acute septic phase. High baseline levels predicted future sepsis (OR 1.81, 95% CI 1.01-3.26), but were not associated with severity of sepsis or in-hospital fatality. Both high MBL levels in the acute phase (OR 4.94, 95% CI 1.44-16.89), and an increase from base line to the acute phase (OR 3.67, 95% CI 1.19-11.28) were associated with increased risk for in-hospital death in women, but not in men (OR 0.71, 95% CI 0.18-2.88). Low levels at baseline were not associated with future sepsis. Neither low levels at baseline, nor in the acute phase were associated with sepsis severity or in-hospital mortality.

    Conclusions: High pre-sepsis levels predicted a future sepsis event, and an increase from baseline to the acute phase as well as high levels in the acute phase associated with an unfavourable outcome in women.

  • 47.
    Jacobsson, Sofie
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Larsson, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Norberg, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Wadell, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi.
    Hallmans, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Näringsforskning.
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Söderberg, Stefan
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Leptin independently predicts development of sepsis and its outcome2017Ingår i: Journal of Inflammation, ISSN 1476-9255, E-ISSN 1476-9255, Vol. 14, artikel-id 19Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Sepsis is a life-threatening condition and obesity is related to the clinical outcome. The underlying reasons are incompletely understood, but the adipocyte derived hormones leptin and adiponectin may be involved.

    Methods: Patients aged 18 years or more with documented first time sepsis events were included in a nested case-referent study if they had participated in previous health surveys. Two matched referents free of known sepsis were identified. Circulating levels of leptin and adiponectin were determined in stored plasma, and their impact on a future sepsis event and its outcome was evaluated.

    Results: We identified 152 patients (62% women) with a sepsis event and a previous participation in a health survey. Eighty-three % had also blood samples from the acute event. Hyperleptinemia at health survey associated with a future sepsis event (OR 1.77, 95% CI 1.04-3.00) and with hospital death. After adjustment for BMI leptin remained associated with sepsis in men, but not in women. High levels in the acute phase associated with increased risk for in hospital death in women (OR 4.18, 95% CI 1.17-15.00), while being protective in men (OR 0.05, 95% CI 0.01-0.48). Furthermore, leptin increased more from baseline to the acute phase in men than in women. Adiponectin did not predict sepsis and did not relate to outcome.

    Conclusions: Hyperleptinemia independently predicted the development of sepsis and an unfavourable outcome in men, and inertia in the acute response related to worse outcome.

  • 48.
    Jensen, Steen
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    On-line computerized vectorcardiography: influence of body position, heart rate, radiographic contrast fluid and myocardial ischemia1997Ingår i: Cardiology, Vol. 88, nr 6, s. 576-84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    On-line computerized vectorcardiography (cVCG) is increasingly being used for continuous monitoring of myocardial ischemia, however, little is known about factors other than ischemia causing electrocardiographic abnormalities. This paper describes how three important cVCG parameters, STC-VM, ST-VM and QRS-VD, are affected by different body positions, myocardial ischemia, contrast injection and increasing heart rate in patients with and without coronary artery disease. The main findings of the study are: contrast injection and different body positions caused major changes in QRS-VD but affected ST-VM and STC-VM to a minor degree. Increasing heart rate by atrial pacing produced substantial changes in all three parameters. Ischemia during angioplasty also produced changes in all three parameters, STC-VM being the most sensitive parameter. In conclusion: (1) STC-VM (> or = 50 microV) is the most valuable parameter for monitoring ischemia; (2) we propose ST-VM > or = 50 microV as criterion instead of previously used 25 microV; (3) QRS-VD cannot be used as a single marker of ischemia, and (4) electrocardiographic changes induced by increased heart rate should be taken into account during interpretation.

  • 49.
    Jensen, Steen
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Osterman, Göran
    Reiz, Sebastian
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    On-line computerized vectorcardiography monitoring of myocardial ischemia during coronary angioplasty: comparison with 12-lead electrocardiography1994Ingår i: Coron Artery Dis, Vol. 5, nr 6, s. 507-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BACKGROUND: With new interventions minimizing ischemic myocardial injury, accurate and reliable techniques for the detection and continuous monitoring of myocardial ischemia are essential. We compared two techniques used for the detection of myocardial ischemia during coronary angioplasty: on-line computerized vectorcardiographic (cVCG) monitoring and the standard electrocardiography (ECG) leads or the complete 12-lead ECG. METHODS: Thirty patients scheduled for routine angioplasty were included in the study. cVCG was recorded continuously. The electrodes were placed according to the lead system described by Frank and connected to a computerized system for on-line vectorcardiography. A 12-lead ECG was recorded simultaneously. The absolute variable spatial ST vector magnitude (ST-VM) and the relative variable spatial ST change vector magnitude (STC-VM) were calculated and compared with the standard 12-lead ECG for the detection of ischemia. RESULTS: The sum of deviation in ST segment in all 12 standard ECG leads correlated closely with STC-VM, irrespective of which artery was occluded. STC-VM indicated ischemia during the first balloon inflation in 87% of the patients and demonstrated ischemia in more patients than the standard 12-lead ECG. Myocardial ischemia was not demonstrated by ST-VM in five out of 26 patients with ischemia according to STC-VM. In these cases, mainly directional vector changes and fewer changes in magnitude were observed. CONCLUSION: Compared with 12-lead ECG, on-line cVCG is a more sensitive method of detecting myocardial ischemia during coronary angioplasty and the reading is easier and faster. Our results support STC-VM > or = 0.050 mV as the criterion for ischemia during angioplasty; ST-VM should be applied together with STC-VM.

  • 50.
    Jensen, Steen
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Karp, Kjell
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Klinisk fysiologi.
    Häggmark, Sören
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Johansson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Näslund, Ulf
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Kardiologi.
    Assessment of myocardium at risk in pigs with single photon emission computed tomography and computerized vectorcardiography during transient coronary occlusion2000Ingår i: Scand Cardiovasc J, Vol. 34, nr 2, s. 142-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Since myocardium at risk (MAR) is the major prognosticator of final infarct size and outcome in patients with acute myocardial infarction, it is highly desirable to estimate the size of the acutely ischemic myocardium, that is the MAR, in these patients. We assessed MAR size by Tc-99m-sestamibi-SPECT and computerized vectorcardiography using autoradiography as reference method. Transient myocardial ischemia was achieved in 12 pigs by coronary artery occlusion with PTCA catheters. During the procedure, computerized vectorcardiography was continuously recorded. After injection of Tc-99m-sestamibi and gadolinium-153-labelled microspheres, MAR size was estimated by SPECT and post-mortem autoradiography. Different cut-off levels (50-70%) were compared with respect to MAR-SPECT. Tc-99m-sestamibi-SPECT showed a good correlation with autoradiography (r = 0.94). Computerized vectorcardiography showed a good correlation with autoradiography as well as with Tc-99m-sestamibi-SPECT (STC-VM: r = 0.75 and 0.80, respectively, ST-VM: 0.75 and 0.87, respectively). It was found that 1) MAR assessed by Tc-99m-sestamibi-SPECT correlates closely with the autoradiographic reference; 2) a lower cut-off point of 60% of maximum uptake for MAR by Tc-99m-sestamibi-SPECT gives the closest correlation with the autoradiographic reference; and 3) ST-VM and STC-VM correlate well with MAR assessed by Tc-99m-sestamibi-SPECT and autoradiography.

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