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  • 1.
    Abrahamsson, Pernilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Methodological aspects on microdialysis sampling and measurements2010Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background:     The microdialysis (MD) technique is widely spread and used both experi­mentally and in clinical practice. The MD technique allows continuous collection of small molecules such as glucose, lactate, pyruvate and glycerol. Samples are often analysed using the CMA 600 analyser, an enzymatic and colorimetric analyser.  Data evaluating the performance of the CMA 600 analysis system and associated sample han­dling are sparse. The aim of this work was to identify sources of variability related to han­dling of microdialysis samples and sources of error associated with use of the CMA 600 analyser. Further, to develop and compare different application techniques of the micro­dialysis probes both within an organ and on the surface of an organ.

     Material and Methods:  Papers I and II are mainly in vitro studies with the exception of the No Net Flux calibration method in paper I where a pig model (n=7) was used to exam­ine the true concen­tration of glucose and urea in subcutaneous tissue. Flow rate, sampling time, vial and caps material and performance of the analyser device (CMA 600) were examined. In papers III and IV normoventilated anaesthetised pigs (n=33) were used. In paper III, heart ischemia was used as intervention to compare microdialysis measurements in the myocardium with corresponding measurements on the heart surface. In paper IV, microdialysis measurements in the liver parenchyma were compared with measurements on the liver surface in associa­tion with induced liver ischemia. All animal studies were approved by the Animal Experi­mental Ethics Committee at Umeå University Sweden.

    Results:  In paper I we succeeded to measure true concentrations of glucose (4.4 mmol/L) and Urea (4.1 mmol/L) in subcutaneous tissue. Paper II showed that for a batch analyse of 24 samples it is preferred to store microdialysis samples in glass vials with crimp caps. For reliable results, samples should be centrifuged before analysis. Paper III showed a new application area for microdialysis sampling from the heart, i.e. surface sampling. The sur­face probe and myocardial probe (in the myocardium) showed a similar pattern for glucose, lactate and glycerol during baseline, short ischemic and long ischemic interventions. In paper IV, a similar pattern was observed as in paper III, i.e. data obtained from the probe on the liver surface showed no differences compared with data from the probe in liver paren­chyma for glucose, lactate and glycerol concentrations during baseline, ischemic and reperfusion interven­tions.

    Conclusion:  The MD technique is adequate for local metabolic monitoring, but requires methodological considerations before starting a new experimental serie. It is important to consider factors such as flow rate, sampling time and handling of samples in association with the analysis device chosen. The main finding in this thesis is that analyses of glucose, lactate and glycerol in samples from the heart surface and liver surface reflect concentra­tions sampled from the myocardium and liver parenchyma, respectively.

  • 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.
    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 analyser2008Inngår i: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 48, nr 5, 940-945 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 3.
    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 parenchyma2016Inngår i: Journal of Surgical Research, ISSN 0022-4804, E-ISSN 1095-8673, Vol. 200, nr 2, 480-487 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 4.
    Abrahamsson, Pernilla
    et al.
    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.
    An assessment of calibration and performance of the microdialysis system2005Inngår i: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 39, nr 3-4, 730-734 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To improve the reliability of microdialysis measurements of tissue concentrations of metabolic substances, this study was designed to test both the performance and the internal validity of the microdialysis methods in the hands of our research group. The stability of the CMA 600 analyser was tested with a known glucose solution in 72 standard microvials and in 48 plastic vials. To evaluate if variation in sampling time makes any difference in sample concentration (recovery), sampling times of 10, 20 and 30 min were compared in vitro with a constant flow rate of 1 microl/min. For testing of sampling times at different flow rates, an in vitro study was performed in which a constant sample volume of 10 microl was obtained. With the no net flux method, the actual concentration of glucose and urea in subcutaneous tissue was measured. The CMA 600 glucose analysis function was accurate and stable with a coefficient of variability (CV) of 0.2-0.55%. There was no difference in recovery for the CMA 60 catheter for glucose when sampling times were varied. Higher flow rates resulted in decreased recovery. Subcutaneous tissue concentrations of glucose and urea were 4.4 mmol/l and 4.1 mmol/l, respectively. To conclude, this work describes an internal validation of our use of the microdialysis system by calibration of vials and catheters. Internal validation is necessary in order to be certain of adequate sampling times, flow rates and sampling volumes. With this in mind, the microdialysis technique is useful and appropriate for in vivo studies on tissue metabolism.

  • 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.
    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 heart2011Inngår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 31, nr 3, 175-181 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 6.
    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) (Annet vitenskapelig)
    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.

  • 7.
    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 model2012Inngår i: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 32, nr 2, 99-105 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 8.
    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 pig2011Inngår i: European Journal of Anaesthesiology, ISSN 0265-0215, E-ISSN 1365-2346, Vol. 28, nr 5, 356-362 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 9.
    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 monoxide2009Inngår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 53, nr 8, 1036-1042 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 10.
    Alfraeus, Simon
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Hypotensive Effect of Anesthesia with Target controlled infusion: A randomized controlled trial2016Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
  • 11.
    Allvin, Renée
    et al.
    Clinical Skills Centre, Faculty of Medicine and Health, School of Medical Sciences, Örebro University, Örebro.
    Berndtzon, Magnus
    Metodikum – Skill Centre of Medical Simulation Region County Jönköping, Jönköping.
    Carlzon, Liisa
    Simulation Centre West, Department of Research, Education and Development, Sahlgrenska University Hospital, Gothenburg.
    Edelbring, Samuel
    Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping.
    Hult, Håkan
    Department of Medical and Health Sciences, Faculty of Medicine and Health Sciences, Linköping University, Linköping.
    Hultin, Magnus
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Karlgren, Klas
    Department of Learning, Informatics, Management and Ethics, Karolinska Institutet, Stockholm.
    Masiello, Italo
    Department of Clinical Science and Education, Karolinska Institutet, Södersjukhuset Hospital, Stockholm.
    Södersved Källestedt, Marie-Louise
    Clinical Skills Centre, Centre for Clinical Research, Uppsala University, Västerås.
    Tamás, Éva
    Department of Cardiovascular Diseases, Institute of Medicine and Health, Medical Faculty, University of Linköping, Linköping.
    Confident but not theoretically grounded: experienced simulation educators’ perceptions of their own professional development2017Inngår i: Advances in Medical Education and Practice, ISSN 1179-7258, E-ISSN 1179-7258, nr 8, 99-108 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Medical simulation enables the design of learning activities for competency areas (eg, communication and leadership) identi ed as crucial for future health care professionals. Simulation educators and medical teachers follow different career paths, and their education backgrounds and teaching contexts may be very different in a simulation setting. Although they have a key role in facilitating learning, information on the continuing professional development (pedagogical development) of simulation educators is not available in the literature. Objectives: To explore changes in experienced simulation educators’ perceptions of their own teaching skills, practices, and understanding of teaching over time.

    Methods: A qualitative exploratory study. Fourteen experienced simulation educators partici- pated in individual open-ended interviews focusing on their development as simulation educators. Data were analyzed using an inductive thematic analysis. Results: Marked educator development was discerned over time, expressed mainly in an altered way of thinking and acting. Five themes were identi ed: shifting focus, from following to utilizing a structure, setting goals, application of technology, and alignment with profession. Being con dent in the role as an instructor seemed to constitute a foundation for the instructor’s pedagogical development.

    Conclusion: Experienced simulation educators’ pedagogical development was based on self- con dence in the educator role, and not on a deeper theoretical understanding of teaching and learning. This is the rst clue to gain increased understanding regarding educational level and possible education needs among simulation educators, and it might generate several lines of research for further studies. 

  • 12.
    Alth, Ellen
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Nutrition av IVA-patienter vid hemodynamisk instabilitet2016Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
  • 13.
    Andersson, Jonas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Sjöström, Lars-Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Karlsson, Marcus
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Wiklund, Urban
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Hultin, Magnus
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Karpe, Fredrik
    Olsson, Tommy
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Dysregulation of subcutaneous adipose tissue blood flow in overweight postmenopausal women2010Inngår i: Menopause: The Journal of the North American Menopause, ISSN 1072-3714, E-ISSN 1530-0374, Vol. 17, nr 2, 365-371 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVE:: A putative link between abdominal obesity and metabolic-vascular complications after menopause may be due to a decreased adipose tissue blood flow (ATBF). The present work aimed to analyze possible changes in ATBF with being overweight and menopausal and its putative link to endothelial dysfunction and autonomic nervous system balance.

    METHODS:: Forty-three healthy women were classified into four groups according to weight and menopause status. The ATBF was measured by xenon washout while fasting and after oral glucose intake. The nitric oxide synthase inhibitor asymmetric dimethylarginine was used as a marker of endothelial function and heart rate variability-estimated autonomic nervous system activity.

    RESULTS:: Fasting ATBF was decreased in both overweight groups (P = 0.044 and P = 0.048) versus normal-weight premenopausal women. Normal-weight and overweight postmenopausal women exhibited lower maximum ATBF compared with normal-weight premenopausal women (P = 0.015 and P = 0.001, respectively), and overweight postmenopausal women exhibited lower maximum ATBF compared with normal-weight postmenopausal women (P = 0.003). A negative correlation was found between fasting ATBF and asymmetric dimethylarginine (P = 0.015), whereas maximum ATBF was negatively associated with sympathetic-parasympathetic nervous system balance (ratio of the power of the low frequency to the power of the high frequency; P = 0.002).

    CONCLUSIONS:: Loss of ATBF flexibility in overweight postmenopausal women may contribute to the metabolic dysfunction seen in this group of women.

  • 14.
    Andersson, Nina
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Grip, Helena
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Sjukgymnastik.
    Lindvall, Peter
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Koskinen, Lars-Owe D
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Brändström, Helge
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Malm, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eklund, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Air transport of patients with intracranial air: computer model of pressure effects2003Inngår i: Aviation, Space and Environmental Medicine, ISSN 0095-6562, Vol. 74, nr 2, 138-144 s.Artikkel i tidsskrift (Fagfellevurdert)
  • 15.
    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 practice1989Inngår i: Scandinavian Journal of Dental Research, ISSN 0029-845X, Vol. 97, nr 5, 456-64 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 16.
    A'roch, Roman
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Left ventricular function's relation to load, experimental studies in a porcine model2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background: Loading conditions are recognized to influence ventricular function according to the Starling relationship for length/stretch and force.  Many modern echocardiographic parameters which have been announced as describing ventricular function and contractile status, may be confounded by uncontrolled and unmeasured load.  These studies aimed to measure the relation between four differ­ent types of assessments of ventricular dysfunction and degrees of load.  Study examined the ‘myo­cardial performance index’ (MPI).  Study II examined long axis segmental mechanical dyssynchrony.  Study III examined tissue velocities, and Study IV examined ventricular twist.  All studies aimed to describe the relation of these parameters both to load and to inotropic changes.

    Methods:  In anesthetized juvenile pigs, left ventricular (LV) pressure and volume were measured continuously and their relationship (LVPVR) was analysed.  Preload alterations were brought about by inflation of a balloon tipped catheter in the inferior vena cava (IVCBO).  Inotropic interventions were brought about by either an overdose of anesthetic (combine intravenous pentobarbital and inhaled isoflurane, Study I), or beta blocker and calcium channel blocker given in combination (Stud­ies III and IV).  In one study (II), global myocardial injury and dysfunction was induced by endotoxin infusion.  MPI measurements were derived from LVPVR heart cycle intervals for isovolumic contrac­tion and relaxation as well as ejection time.  Long axis segmental dyssynchrony was derived by ana­lyzing for internal flow and time with segmental dyssynchronous segment volume change during systole, hourly before and during 3 hours of endotoxin infusion.  Myocardial tissue velocities were measured during IVCBO at control, during positive and then later negative inotropic interventions.  The same for apical and base circumferential rotational velocities by speckle tracking.  Load markers (including end-diastolic volume) were identified for each beat, and the test parameters were analysed together with load for a relation.  The test parameters were also tested during single apneic beats for a relation to inotropic interventions.

    Results: MPI demonstrated a strong and linear relationship to both preload and after-load, and this was due to changes in ejection time, and not the isovolumic intervals.  Long axis segmental dyssyn­chrony increased during each hour of endotoxin infusion and global myocardial injury.  This dysyn­chrony parameter was independent of load when tested by IVCBO. Peak systolic velocities were strongly load-independent, though not in all the inotropic situations and by all measurement axes.  Peak systolic strain was load-dependent, and not strongly related to inotropic conditions.  Peak sys­tolic LV twist and untwist were strongly load-dependent.

    Conclusions: MPI is strongly load-dependent, and can vary widely in value for the same contractile status if the load is varied.  Mechanical dyssynchrony measures are load-independen in health and also in early global endotoxin myocardial injury and dysfunction.  Peak sytole velocities are a clinically robust parameter of LV regional and global performance under changing load, though peak systolic strain seems to be load-dependent.  Left ventricular twist and untwist are load-dependent in this pig model.

  • 17.
    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 model2012Inngår i: Cardiovascular Ultrasound, ISSN 1476-7120, Vol. 10, nr 22Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 18.
    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) (Annet vitenskapelig)
    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.

  • 19.
    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) (Annet vitenskapelig)
    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.

  • 20.
    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 load2012Inngår i: Cardiovascular Ultrasound, ISSN 1476-7120, Vol. 10, nr 26Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 21.
    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 model2009Inngår i: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 196, nr 4, 375-383 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 22.
    Axelsson, Birger
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Cardiac effects of non-adrenergic inotropic drugs: clinical and experimental studies2013Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background: Myocardial failure and dysfunction is not uncommon during critical illness and following cardiac surgery. For optimal treatment, a better understanding of the effects of inotropic drugs is needed. In this thesis, two non-adrenergic mediated inotropes, milrinone and levosimendan were studied in different models of myocardial dysfunction. The study aims were to assess the following: the effects of milrinone on blood flow in coronary artery bypass grafts during CABG surgery; the effects of milrinone on left ventricular diastolic function during post-ischaemic myocardial dysfunction; whether milrinone or levosimendan are protective or injurious during acute myocardial ischaemia, and if levosimendan potentiates myocardial function when added to milrinone in an experimental model of post-ischaemic (stunned) myocardium.

    Material and Methods: In Study I, 44 patients undergoing coronary artery bypass surgery(CABG) were included as subjects. Milrinone or saline was administrated in a single dose during cardio-pulmonary bypass (CPB) and coronary graft flow measurements were recorded after 10 and 30 min following CPB. In Study II; 24 patients undergoing CABG had estimations of peak ventricular filling rates made before and after CPB with administration of milrinone or saline as a single dose during CPB, performed by assessment of the rate of change in diastolic cross-sectional left ventricular area. In Study III, energy-metabolic effects of milrinone and levosimendan were measured in an anaesthetized porcine model during 45 minutes of regional myocardial ischemia. Microdialysis sampling of metabolites of local ischemic metabolism allowed assessment of glycolytic activity and the degree of myocardial calcium overload. In Study IV, in a porcine model of postischaemic myocardial stunning, ventricular pressure-volume relationships were analyzed when milrinone or a combination of milrinone and levosimendan were given together.

    Results: In Study I, there was a clear increase in non-sequential saphenous vein graft blood flow with milrinone at 10 minutes (64.5 ± 37.4 compared to placebo 43.6 ± 25.7 ml/min (mean ± SD).). A decreasing but still measureable flow increase was seen for milrinone at 30 minutes. In Study II, an increase in early left ventricular filling rate (ventricular cross-sectional area rate of change,dA/dt) was seen in the milrinone treated group. Pre-bypass milrinone group dA/dt 22.0 ± 9.5 changed to post-bypass values dA/dt 27.8 ± 11.5 cm2/sec). Placebo group pre-bypass dA/dt was 21.0 ± 8.7 and post-bypass 17.1 ± 7.1 cm2/sec. A milrinone effect was demonstrated in an adjusted regression model (p = 0.001). In Study III, neither milrinone nor levosimendan led to a change in energy-metabolic activity during ischemia as reflected by interstitial glucose, pyruvate, lactate orglycerol. Neither drug exacerbated the relative myocardial calcium overload during ischemia. In Study IV, milrinone improved active relaxation (tau) in post-ischemic stunned myocardium, but did not markedly improve systolic function by preload recruitable stroke work. Levosimendan added to milrinone showed minimal effect on active relaxation but a positive effect on systolic function in combination with milrinone.

    Conclusions: We conclude that milrinone treatment leads to an increase in blood flow in newly implanted coronary saphenous vein grafts, and improves ventricular relaxation post-cardiopulmonary bypass. Neither milrinone nor levosimendan, in this porcine model, negatively influence myocardial energy metabolism or calcium overload during acute ischaemia. Addition of levosimendan to milrinone treatment during post-ischaemic ventricular dysfunction may provide additive inotropic effects on systolic function but probably not for active relaxation.

  • 23.
    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 kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    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 Model2016Inngår i: Journal of Cardiovascular Pharmacology and Therapeutics, ISSN 1074-2484, E-ISSN 1940-4034, Vol. 21, nr 5, 495-503 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 24.
    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) (Annet vitenskapelig)
  • 25.
    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 metabolism2013Inngår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 57, nr 6, 719-728 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 26.
    Bertilsson, Sandra
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Mortalitet och vårdbehov hos patienter med dialyskrävande njursvikt efter hjärtkirurgi2015Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
  • 27.
    Björklin, Josefin
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    The effect of spinal anaesthesia in postoperative analgesia after caesarean sections - comparison between adjuvant morphine and fentanyl2017Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
  • 28. 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 model2012Inngår i: European Surgical Research, ISSN 0014-312X, E-ISSN 1421-9921, Vol. 49, nr 3-4, 113-120 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 29.
    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 performance2001Inngår i: Acta Anaesthesiol Scand, Vol. 45, nr 9, 1147-54 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 30.
    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.2004Inngår i: Acta Physiologica Scandinavica, ISSN 0001-6772, Vol. 182, nr 2, 111-9 s.Artikkel i tidsskrift (Fagfellevurdert)
  • 31.
    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 infusion2002Inngår i: Anesth Analg, Vol. 94, nr 4, 787-93, table of contents s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 32.
    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 nitroprusside2000Inngår i: Acta Anaesthesiol Scand, Vol. 44, nr 10, 1238-45 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 33.
    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 dependent2002Inngår i: Acta Anaesthesiol Scand, Vol. 46, nr 1, 57-63 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 34.
    Brorsson, Camilla
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Trauma - logistics and stress response2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background: Trauma is a major cause of death and disability. Adverse events, such as prolonged prehospital time, hypoxia, hypotension and/or hyperventilation have been reported to correlate to poor outcome.

    Adequate cortisol levels are essential for survival after major trauma. In hypotensive critically ill patients, lack of sufficient amount of cortisol can be suspected, and a concept of critical illness related corticosteroid insufficiency has been proposed. Corticosteroid therapy has many adverse effects in critically ill patients and should only be given if life-saving. Correct measurement of serum cortisol levels is important but difficult in critically ill patients with capillary leakage. Estimation of the free and biologically active cortisol is preferable. In serum less than 10% of cortisol is free and biologically active and not possible to measure with routine laboratory methods. Salivary cortisol can be used as a surrogate for free cortisol, but salivary production is reduced in critically ill patients. Liver resection could reduce cortisol levels due to substrate deficiency.

    Aims: 1. Evaluate the occurrence of early adverse events in patients with traumatic brain injury and relate them to outcome. 2. Assess cortisol levels over time after trauma and correlate to severity of trauma, sedative/analgesic drugs and cardiovascular function. 3. Evaluate if saliva stimulation could be performed without interfering with salivary cortisol levels. 4. Assess cortisol levels over time after liver resection in comparison to other major surgery.

    Results: There was no significant correlation between prehospital time ³60 minutes, hypoxia (saturation <95%), hypotension (systolic blood pressure <90 mmHg), or hyperventilation (ETCO2 <4.5 kPa) and a poor outcome (Glasgow Outcome Scale 1-3) in patients with traumatic brain injury. Cortisol levels decreased significantly over time after trauma, but there was no correlation between low (<200 nmol/L) serum cortisol levels and severity of trauma.

    Infusion of sedative/analgesic drugs was the strongest predictor for a low (<200 nmol/L) serum cortisol. The odds ratio for low serum cortisol levels (<200 nmol/L) was 8.0 for patients receiving continuous infusion of sedative/analgesic drugs. There was no significant difference between unstimulated and stimulated salivary cortisol levels (p=0.06) in healthy volunteers. Liver resection was not associated with significantly lower cortisol levels compared to other major surgery.

    Conclusion: There was no significant correlation between early adverse events and outcome in patients with traumatic brain injury. Cortisol levels decreased significantly over time in trauma patients. Low cortisol levels (<200 nmol/L) were significantly correlated to continuous infusion of sedative/analgesic drugs. Saliva stimulation could be performed without interfering with salivary cortisol levels. Liver resection was not associated with low cortisol levels compared to other major surgery.

  • 35.
    Brorsson, Camilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Dahlqvist, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Lundberg, Owe
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Naredi, Peter
    Kirurgi, Sahlgrenska, Göteborg.
    Naredi, Silvana
    Anestesiologi, Sahlgrenska, Göteborg.
    Liver resection is not associated with decreased cortisol levels.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Adrenal hormones are synthesized from cholesterol, produced and stored in the liver. Liver failure has been reported to be associated with adrenal insufficiency. A possible mechanism could be a limited supply of substrate for cortisol synthesis. The aims of this study was to evaluate the occurrence of total serum cortisol <200 nmol/L after major liver resection (≥ 30%) and other major surgery (hemicolectomy) and to assess associations between cholesterol and corti­sol levels after liver resection.

    Methods: Prospective, observational study. 40 patients were included (major liver resection n=15, hemicolectomy n=25). Serum and salivary cortisol were followed from morning before surgery up to five days postoperatively. Sulphated dehy­droepiandrosterone (DHEAS) and lipids (cholesterol, low density lipoproteins, high density lipoproteins and triglycerides) were obtained in liver resection patients.

    Results: 8/25 (32%, hemicolectomy patients), and 3/15 (20%, liver resection patients) had serum cortisol <200 nmol/L. Neither hemicolectomy nor liver resec­tion was significantly associated with serum cortisol <200 nmol/L, p=0.49. Serum cortisol <200 nmol/L was not significantly associated with lipids below normal limits, (cholesterol; p=1.0 day 1, p=0.46 day 4, LDL; p=0.56 day 1, p=1.0 day 4, and HDL; p=0.27 day 1, p=1.0 day 4). Serum and salivary cortisol correlated sig­nificantly (rs=0.83, p<0.0001, hemicolectomy, rs=0.80, p<0.0001, liver resection).

    Conclusion: Serum cortisol levels <200 nmol/L was found in 32% (hemicolec­tomy) and 20% (liver resection) postoperatively. Compared to after hemicolec­tomy, serum cortisol <200 nmol/L was not significantly more common after liver resection. Lipids below normal limits were not associated with serum cortisol <200 nmol/L after liver resection.

    Key words: gastrointestinal surgical procedures, adrenal insufficiency, hydrocortisone

  • 36.
    Brorsson, Camilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Dahlqvist, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Nilsson, Leif
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Naredi, Silvana
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Saliva stimulation with glycerine and citric acid does not affect salivary cortisol levels2014Inngår i: Clinical Endocrinology, ISSN 0300-0664, E-ISSN 1365-2265, Vol. 81, nr 2, 244-248 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    OBJECTIVE:

    In critically ill patients with hypotension, who respond poorly to fluids and vasoactive drugs, cortisol insufficiency may be suspected. In serum over 90% of cortisol is protein-bound, thus routine measures of total serum cortisol may yield 'false lows' due to hypoproteinaemia. Thus, the occurrence of cortisol insufficiency could be overestimated in critically ill patients. Salivary cortisol can be used as a surrogate for free serum cortisol, but in critically ill patients saliva production is decreased, and insufficient volume of saliva for analysis is a common problem. The aim of this study was to investigate if a cotton-tipped applicator with glycerine and citric acid could be used for saliva stimulation without affecting salivary cortisol levels.

    DESIGN:

    Prospective, observational study.

    PARTICIPANTS:

    Thirty-six volunteers (six males, 30 females), age 49 ± 9 years, without known oral mucus membrane rupture in the mouth.

    MEASUREMENTS:

    Forty-two pairs of saliva samples (22 paired morning samples, 20 paired evening samples) were obtained before and after saliva stimulation with glycerine and citric acid. Salivary cortisol was analysed using Spectria Cortisol RIA (Orion Diagnostica, Finland).

    RESULTS:

    The paired samples correlated significantly (P < 0·0001) and there was no significant difference between un-stimulated and stimulated salivary cortisol levels.

    CONCLUSIONS:

    Saliva stimulation with a cotton-tipped applicator containing glycerine and citric acid did not significantly influence salivary cortisol levels in healthy volunteers. This indicates that salivary cortisol measurement after saliva stimulation may be a useful complement when evaluating cortisol status in critically ill patients.

  • 37.
    Brorsson, Camilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Dahlqvist, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Nilsson, Leif
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Thunberg, Johan
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Sylvan, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Naredi, Silvana
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Adrenal response after trauma is affected by time after trauma and sedative/analgesic drugs2014Inngår i: Injury, ISSN 0020-1383, E-ISSN 1879-0267, Vol. 45, nr 8, 1149-1155 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: The adrenal response in critically ill patients, including trauma victims, has been debated over the last decade. The aim of this study was to assess the early adrenal response after trauma. METHODS: Prospective, observational study of 50 trauma patients admitted to a level-1-trauma centre. Serum and saliva cortisol were followed from the accident site up to five days after trauma. Corticosteroid binding globulin (CBG), dehydroepiandrosterone (DHEA) and sulphated dehydroepiandrosterone (DHEAS) were obtained twice during the first five days after trauma. The effect of time and associations between cortisol levels and; severity of trauma, infusion of sedative/analgesic drugs, cardiovascular dysfunction and other adrenocorticotropic hormone (ACTH) dependent hormones (DHEA/DHEAS) were studied. RESULTS: There was a significant decrease over time in serum cortisol both during the initial 24 h, and from the 2nd to the 5th morning after trauma. A significant decrease over time was also observed in calculated free cortisol, DHEA, and DHEAS. No significant association was found between an injury severity score >/= 16 (severe injury) and a low (< 200 nmol/L) serum cortisol at any time during the study period. The odds for a serum cortisol < 200 nmol/L was eight times higher in patients with continuous infusion of sedative/analgesic drugs compared to patients with no continuous infusion of sedative/analgesic drugs. CONCLUSION: Total serum cortisol, calculated free cortisol, DHEA and DHEAS decreased significantly over time after trauma. Continuous infusion of sedative/analgesic drugs was independently associated with serum cortisol < 200 nmol/L.

  • 38.
    Brorsson, Camilla
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Rodling-Wahlström, Marie
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Olivecrona, Magnus
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap.
    Koskinen, Lars-Owe
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap.
    Naredi, Silvana
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Severe traumatic brain injury: consequences of early adverse events2011Inngår i: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 55, nr 8, 944-951 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Several factors associated with an unfavourable outcome after severe traumatic brain injury (TBI) have been described: prolonged pre-hospital time, secondary referral to a level 1 trauma centre, the occurrence of secondary insults such as hypoxia, hypotension or low end-tidal carbon dioxide (ETCO(2)). To determine whether adverse events were linked to outcome, patients with severe TBI were studied before arrival at a level 1 trauma centre.

    Methods: Prospective, observational study design. Patients with severe TBI (n = 48), admitted to Umea University Hospital between January 2002 to December 2005 were included. All medical records from the site of the accident to arrival at the level 1 trauma centre were collected and evaluated.

    Results: A pre-hospital time of >60 min, secondary referral to a level 1 trauma centre, documented hypoxia (oxygen saturation <95%), hypotension (systolic blood pressure <90 mmHg), hyperventilation (ETCO(2) <4.5 kPa) or tachycardia (heart rate >100 beats/min) at any time before arrival at a level 1 trauma centre were not significantly related to an unfavourable outcome (Glasgow Outcome Scale 1-3).

    Conclusion: Early adverse events before arrival at a level 1 trauma centre were without significance for outcome after severe TBI in the trauma system studied.

  • 39.
    Bruno, Erik
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Omvårdnadsåtgärder inom intensivvården - till mer skada än nytta för patienten?2012Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
  • 40.
    Brändstrom, H.
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Rydvall, A.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Stegmayr, B.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Söderberg-Svanström, J.
    Wikdahl, A. M.
    [A killer bacteria caused fasciitis with sepsis. Prompt handling saved the patient's life]1996Inngår i: Lakartidningen, Vol. 93, nr 42, 3687-9 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [sv]

    The article consists in a case report of a patient with rapidly progressive pain in the axillary region and deterioration in his clinical condition during the course of a skin infection, found to have pectoral muscle fascitis, and in whom progressive septic shock was accompanied by multiorgan failure. Blood culture yielded streptococci group A type 1 M1. In addition to conventional intensive care, he was treated with antibiotics, inotropic drugs, plasma exchange, and infusion of antithrombin and immunoglobulin. Surgical intervention such as fasciotomy was avoided initially and later proved unnecessary as the patient recovered well.

  • 41.
    Brändström, Helge
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Accidental hypothermia and local cold injury: physiological and epidemiological studies on risk2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background: (Papers I and II) The objectives were to first determine incidence and contributing factors to cold-related injuries in northern Sweden, both those that led to hospitalization and those that led to fatality.  (Papers III and IV) A further aim was to assess post-cooling hand-rewarming responses and effects of training in a cold environment, both on fingertip rewarming and on function of the autonomic nervous system, to evaluate if there was adaptation related to prolonged occupational cold exposure.

    Methods:  In a retrospective analysis, cases of accidental cold-related injury with hospital admission in northern Sweden during 2000-2007 were analyzed (Paper I).  Cases of fatal hypothermia in the same region during 1992-2008 were analyzed (Paper II).  A cohort of volunteers was studied before and after many months of occupational cold exposure. Subject hand rewarming response was measured after a cold hand immersion provocation and categorized as slow, moderate or normal in rewarming speed.  This cold provocation and rewarming assessment was performed before and after their winter training.  (Paper III).  Heart rate variability (HRV) was analyzed from the same cold provocation/recovery sequences (Paper IV).

    Results:  (Paper I) For the 379 cases of hospitalization for cold-related injury, annual incidences for hypothermia, frostbite, and drowning were 3.4/100,000, 1.5/100,000, and 1.0/100,000 inhabitants, respectively.  Male gender was more frequent for all categories.  Annual frequencies for hypothermia hospitalizations increased during the study period.  Hypothermia degree and distribution of cases were 20 % mild (between 32 and 35ºC), 40% moderate (31.9 to 28ºC), and 24% severe (< 28ºC), while 12% had temperatures over 35.0ºC.  (Paper II) The 207 cases of fatal hypothermia showed an annual incidence of 1.35 per 100,000 inhabitants, 72% in rural areas, 93% outdoors, 40% found within 100 meters of a building.  Paradoxical undressing was documented in 30%.  Ethanol was detected in femoral vein blood in 43%. Contributing co-morbidity was common including heart disease, previous stroke, dementia, psychiatric disease, alcoholism, and recent trauma.  (Paper III) Post-training, baseline fingertip temperatures and cold recovery variables in terms of final rewarming fingertip temperature and vasodilation time increased significantly in moderate and slow rewarmers.  Cold-related injury (frostbite) during winter training occured disproportionately more often in slow rewarmers (4 of the 5 injuries).  (Paper IV) At ‘pre- winter-training’, normal rewarmers had higher power for low frequency and high frequency heart rate variability.  After cold acclimatization (post-training), normal rewarmers showed lower resting power values for the low frequency and high frequency heart rate variability components. 

    Conclusions: Hypothermia and cold injury continues to cause injury and hospitalization in the northern region of Sweden.  Assessment and management is not standardized across hospitals.  With the identification of groups at high risk for fatal hypothermia, it should be possible to reduce the incidence, particularly for highest risk subjects; rural, living alone, alcohol-imbibing, and psychiatric diagnosis-carrying citizens.  Long-term cold-weather training may affect hand rewarming patters after a cold provocation, and a warmer baseline hand temperature with faster rewarming after a cold provocation may be associated with less general risk for frostbite.  Heart rate variability results support the conclusion that cold adaptation in the autonomic nervous system occurred in both groups, though the biological significance of this is not yet clear.

  • 42.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Eriksson, Anders
    Umeå universitet, Medicinska fakulteten, Institutionen för samhällsmedicin och rehabilitering, Rättsmedicin.
    Giesbrecht, Gordon
    University of Manitoba, Winnipeg, Canada. Dep of Anesthesia.
    Ängquist, Karl-Axel
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Fatal hypothermia: an analysis from a sub-arctic region2012Inngår i: International Journal of Circumpolar Health, ISSN 1239-9736, Vol. 71, nr 0, 1-7 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Objectives. To determine the incidence as well as contributing factors to fatal hypothermia.

    Study design. Retrospective, registry-based analysis.

    Methods. Cases of fatal hypothermia were identified in the database of the National Board of Forensic Medicine for the 4 northernmost counties of Sweden and for the study period 1992-2008. Police reports, medical records and autopsy protocols were studied.

    Results. A total of 207 cases of fatal hypothermia were noted during the study period, giving an annual incidence of 1.35 per 100,000 inhabitants. Seventy-two percent occurred in rural areas, and 93% outdoors. Many (40%) were found within approximately 100 meters of a building. The majority (75%) occurred during the colder season (October to March). Some degree of paradoxical undressing was documented in 30%. Ethanol was detected in femoral vein blood in 43% of the victims. Contributing co-morbidity was common and included heart disease, earlier stroke, dementia, psychiatric disease, alcoholism, and recent trauma.

    Conclusions. With the identification of groups at high risk for fatal hypothermia, it should be possible to reduce risk through thoughtful interventions, particularly related to the highest risk subjects (rural, living alone, alcohol-imbibing, and psychiatric diagnosis-carrying) citizens.

  • 43.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Giesbrecht, Gordon
    Winsö, Ola
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Ängquist, Karl-Axel
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Accidental cold-related injury leading to hospitalization in northern Sweden (2000-2007)Manuskript (preprint) (Annet vitenskapelig)
  • 44.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Grip, Helena
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Hallberg, Per
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Centrum för medicinsk teknik och fysik (CMTF).
    Grönlund, Christer
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Ängquist, Karl-Axel
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Giesbrecht, Gordon G
    Hand cold recovery responses before and after 15 months of military training in a cold climate2008Inngår i: Aviation, Space and Environmental Medicine, ISSN 0095-6562, E-ISSN 1943-4448, Vol. 79, nr 9, 904-908 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    INTRODUCTION: The ability of fingers to rapidly rewarm following cold exposure is a possible indicator of cold injury protection. We categorized the post-cooling hand-rewarming responses of men before and after participation in 15 mo of military training in a cold environment in northern Sweden to determine: 1) if the initial rewarming category was related to the occurrence of local cold injury during training; and 2) if cold training affected subsequent hand-rewarming responses. METHODS: Immersion of the dominant hand in 10 degrees C water for 10 min was performed pre-training on 77 men. Of those, 45 were available for successful post-training retests. Infrared thermography monitored the dorsal hand during 30 min of recovery. Rewarming was categorized as normal, moderate, or slow based on mean fingertip temperature at the end of 30 min of recovery (TFinger,30) and the percentage of time that fingertips were vasodilated (%VD). RESULTS: Cold injury occurrence during training was disproportionately higher in the slow rewarmers (four of the five injuries). Post-training, baseline fingertip temperatures and cold recovery variables increased significantly in moderate and slow rewarmers: TFinger30 increased from 21.9 +/- 4 to 30.4 +/- 6 degrees C (Moderate), and from 17.4 +/- 0 to 22.3 +/- 7 degrees C (Slow); %VD increased from 27.5 +/- 16 to 65.9 +/- 34% (Moderate), and from 0.7 +/- 2 to 31.7 +/- 44% (Slow). CONCLUSIONS: Results of the cold recovery test were related to the occurrence of local cold injury during long-term cold-weather training. Cold training itself improved baseline and cold recovery in moderate and slow rewarmers.

  • 45.
    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 analysis2014Inngår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, ISSN 1757-7241, E-ISSN 1757-7241, Vol. 22, 6- s.Artikkel i tidsskrift (Fagfellevurdert)
    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).

  • 46.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Sedig, Karin
    Lundälv, Jörgen
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    KAMEDO report no. 77: sinking of the MS Sleipner, 26 November 19992006Inngår i: Prehospital and Disaster Medicine, ISSN 1049-023X, Vol. 21, nr 2 Suppl 2, 115-116 s.Artikkel i tidsskrift (Fagfellevurdert)
  • 47.
    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 simulation2017Inngår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, ISSN 1757-7241, E-ISSN 1757-7241, Vol. 25, 50Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 48.
    Brändström, Helge
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Wiklund, Urban
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Karlsson, Marcus
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Ängquist, Karl-Axel
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Kirurgi.
    Grip, Helena
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Autonomic nerve system responses for normal and slow rewarmers after hand cold provocation: effects of long-term cold climate training2013Inngår i: International Archives of Occupational and Environmental Health, ISSN 0340-0131, E-ISSN 1432-1246, Vol. 86, nr 3, 357-365 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    PURPOSE: Differences among individuals concerning susceptibility to local cold injury following acute cold exposure may be related to function of the autonomic nervous system. We hypothesized that there are differences in heart rate variability (HRV) between individuals with normal or more pronounced vasoconstriction following cold exposure and that there is an adaptation related to prolonged cold exposure in autonomic nervous system response to cold stimuli.

    METHODS: Seventy-seven young men performed a cold provocation test, where HRV was recorded during cold hand immersion and recovery. Forty-three subjects were re-examined 15 months later, with many months of cold weather training between the tests. Subjects were analyzed as 'slow' and 'normal' rewarmers according to their thermographic rewarming pattern.

    RESULTS: For the 'pre-training' test, before cold climate exposure, normal rewarmers had higher power for low-frequency (P(LF)) and high-frequency (P(HF)) HRV components during the cold provocation test (ANOVA for groups: p = 0.04 and p = 0.005, respectively). There was an approximately 25 % higher P(HF) at the start in normal rewarmers, in the logarithmic scale. Low frequency-to-high frequency ratio (P(LF)/P(HF)) showed lower levels for normal rewarmers (ANOVA for groups: p = 0.04). During the 'post-training' cold provocation test, both groups lacked the marked increase in heart rate that occurred during cold exposure at the 'pre-training' setting. After cold acclimatization (post-training), normal rewarmers showed lower resting power values for the low-frequency and high-frequency HRV components. After winter training, the slow rewarmers showed reduced low-frequency power for some of the cold provocation measurements but not all (average total P(LF), ANOVA p = 0.05), which was not present before winter training.

    CONCLUSIONS: These HRV results support the conclusion that cold adaptation occurred in both groups. We conclude that further prospective study is needed to determine whether cold adaptation provides protection to subjects at higher risk for cold injury, that is, slow rewarmers.

  • 49.
    Brändström, Helge
    et al.
    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.
    Lindholm, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Haney, Michael
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Regional intensive care transports: a prospective analysis of distance, time and cost for road, helicopter and fixed-wing ambulances2014Inngår i: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, ISSN 1757-7241, E-ISSN 1757-7241, Vol. 22, 36- s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: There are three different types of ambulance systems, all of which can manage the same secondary intensive care patient transport mission: road ambulance, rotor-wing ambulance, and fixed-wing ambulance. We hypothesized that costs for specific transport distances would differ between systems. We aimed to analyze distances and observed times for ambulance intensive care secondary transport missions together with system costs to assess this. Methods: We prospectively collected data for consecutive urgent intensive care transports into the regional tertiary care hospital in the northern region of Sweden. Distances and transport times were gathered, and a cost model was generated based on these together with fixed and operating costs from the three different ambulance systems. Distance-cost and time-cost estimations were then generated for each transport system. Results: Road ambulance cost relatively less for shorter distances (within 250 kilometers/155 miles) but were relatively time ineffective. The rotor-wing systems were most expensive regardless of distance; but were most time-effective up to 400-500 km (248-310 miles). Fixed-wing systems were more cost-effective for longer distance (300 km/186 miles), and time effective for transports over 500 km (310 miles). Conclusions: In summary, based on an economic model developed from observed regional ICU patient transports, and cost estimations, different ambulance system cost-distances could be compared. Distance-cost and time results show that helicopters can be effective up to moderate ICU transport distances (400-500), though are expensive to operate. For longer ICU patient transports, fixed-wing transport systems are both cost and time effective compared to helicopter-based systems.

  • 50.
    Byström, Emma
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap, Anestesiologi och intensivvård.
    Postoperative nausea andvomiting in ambulatory surgeryHas it improved?2015Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
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