umu.sePublications
Change search
Refine search result
12 1 - 50 of 53
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Anderson, M
    et al.
    Domellöf, L
    Eksborg, S
    Häggmark, S
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, G
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, S
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Herslöf, Å
    Pharmacokinetics and Central Haemodynamic Effects of Doxorubicin and 4'Epi-Doxorubicin in the Pig1989In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 28, no 5, p. 709-714Article in journal (Refereed)
  • 2.
    Andersson, Magnus
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Domellöf, Lennart
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Gustavsson, Bengt
    Cardiopulmonary hemodynamics and pharmacokinetics after hepatic intraarterial infusion of 5-fluorouracil (5-FU)1988In: Cancer Chemotherapy and Pharmacology, ISSN 0344-5704, E-ISSN 1432-0843, Vol. 22, no 3, p. 251-255Article in journal (Refereed)
  • 3.
    Andersson-Wenckert, Ingrid
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Lindkvist, Robert
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Anevac-D, a new system for close scavenging of anesthetic gases in dental practice1989In: Scandinavian Journal of Dental Research, ISSN 0029-845X, Vol. 97, no 5, p. 456-64Article in journal (Refereed)
    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.

  • 4.
    Axelsson, Birger
    et al.
    Örebro University, Örebro, Sweden .
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Svenmarker, Staffan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Gupta, Anil
    Örebro University, Örebro, Sweden .
    Tyden, Hans
    Örebro University, Örebro, Sweden .
    Wouters, Patrick
    Ghent, Belgium.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Effects of Combined Milrinone and Levosimendan Treatment on Systolic and Diastolic Function During Postischemic Myocardial Dysfunction in a Porcine Model2016In: Journal of Cardiovascular Pharmacology and Therapeutics, ISSN 1074-2484, E-ISSN 1940-4034, Vol. 21, no 5, p. 495-503Article in journal (Refereed)
    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.

  • 5.
    Axelsson, Birger
    et al.
    Dept of Cardiovascular and Thoracic Surgery and Anesthesiology and Intensive Care, Örebro University Hospital.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Svenmarker, Staffan
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    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 University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Systolic and diastolic effects of milrinone and levosimendan in porcine post-ischemic myocardial dysfunctionManuscript (preprint) (Other academic)
  • 6.
    Broomé, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Haney, Michael
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Åneman, Anders
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Acute effects of angiotensin II on myocardial performance2001In: Acta Anaesthesiol Scand, Vol. 45, no 9, p. 1147-54Article in journal (Refereed)
    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.

  • 7.
    Broomé, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Haney, Michael
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Åneman, Anders
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Pressure-independent cardiac effects of angiotensin II in pigs.2004In: Acta Physiologica Scandinavica, ISSN 0001-6772, Vol. 182, no 2, p. 111-9Article in journal (Refereed)
  • 8.
    Broomé, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Haney, Michael
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Österlund, Barbro
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    The cardiac effects of intracoronary angiotensin II infusion2002In: Anesth Analg, Vol. 94, no 4, p. 787-93, table of contentsArticle in journal (Refereed)
    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.

  • 9.
    Broomé, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Åneman, Anders
    Haney, Michael
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Angiotensin II mesenteric and renal vasoregulation: dissimilar modulatory effects with nitroprusside2000In: Acta Anaesthesiol Scand, Vol. 44, no 10, p. 1238-45Article in journal (Refereed)
    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.

  • 10.
    Bålfors, E.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nyhman, H.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Rydvall, A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Droperidol inhibits the effects of intravenous ketamine on central hemodynamics and myocardial oxygen consumption in patients with generalized atherosclerotic disease1983In: Anesth Analg, Vol. 62, no 2, p. 193-7Article in journal (Refereed)
    Abstract [en]

    A 2-mg/kg dose of ketamine was administered intravenously to 16 patients with generalized atherosclerotic disease. Eight patients were given 200 mu/kg of droperidol intravenously 10 min before ketamine administration; eight patients not given droperidol served as controls. Central hemodynamics, coronary flow (thermodilution technique) and myocardial oxygen, lactate, hypoxanthine, and catecholamine balances were studied. In control patients, ketamine increased mean blood pressure by 42%, pulmonary capillary wedge pressure by 144%, mean right atrial pressure by 60%, heart rate by 15%, and systemic vascular resistance by 40% without changes in cardiac index, stroke volume index, or left ventricular stroke work index. These data indicate that cardiac performance did not increase in parallel with the rise in afterload. However, the 50% increase in myocardial oxygen demand was associated with a 48% increase in coronary blood flow without changes in coronary vascular resistance or myocardial oxygen extraction. Augmented sympathetic activity was manifested by 397% and 164% increases in plasma levels of epinephrine and norepinephrine, respectively. The hemodynamic and cardiometabolic effects of ketamine were abolished when patients were pretreated with droperidol. The increase in plasma epinephrine levels was likewise inhibited by droperidol; significantly lower plasma norepinephrine levels also were observed. These findings suggest that droperidol inhibits the cardiovascular effects of ketamine by a centrally mediated reduction in sympathetic activity and by peripheral alpha receptor blockade.

  • 11.
    Haney, Michael F
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    ST changes and temporal relation to the J point during heart rate increase and myocardial ischemia.2009In: Journal of electrocardiology, ISSN 1532-8430, Vol. 42, no 1, p. 6-11Article in journal (Refereed)
    Abstract [en]

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

  • 12.
    Haney, Michael F
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Myocardial systolic function increases during positive pressure lung inflation.2005In: Anesthesia and Analgesia, ISSN 0003-2999, Vol. 101, no 5, p. 1269-74Article in journal (Refereed)
    Abstract [en]

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

  • 13.
    Haney, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Analysis of left ventricular systolic function during elevated external cardiac pressures: an examination of measured transmural left ventricular pressure during pressure-volume analysis2001In: Acta Anaesthesiol Scand, Vol. 45, no 7, p. 868-74Article in journal (Refereed)
    Abstract [en]

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

  • 14.
    Haney, Michael
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Heart-lung interactions during positive pressure ventilation: left ventricular pressure-volume momentary response to airway pressure elevation2001In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 45, no 6, p. 702-709Article in journal (Refereed)
    Abstract [en]

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

  • 15.
    Haney, Michael
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Method of preload reduction during LVPVR analysis of systolic function: airway pressure elevation and vena cava occlusion2002In: Anesthesiology, Vol. 97, no 2, p. 436-46Article in journal (Refereed)
    Abstract [en]

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

  • 16.
    Hohner, P.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Backman, C.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Diamond, G.
    Friedman, A.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, G.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Karp, K.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Reiz, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Anaesthesia for abdominal aortic surgery in patients with coronary artery disease, Part II: Effects of nitrous oxide on systemic and coronary haemodynamics, regional ventricular function and incidence of myocardial ischaemia1994In: Acta Anaesthesiol Scand, Vol. 38, no 8, p. 793-804Article in journal (Refereed)
    Abstract [en]

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

  • 17.
    Hohner, Per
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nancarrow, Craig
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Backman, Clas
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Fridén, Håkan
    Diamond, George
    Friedman, Arnold
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Anaesthesia for abdominal vascular surgery in patients with coronary artery disease (CAD), Part I: Isoflurane produces dose-dependent coronary vasodilation1994In: Acta Anaesthesiol Scand, Vol. 38, no 8, p. 780-92Article in journal (Refereed)
    Abstract [en]

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

  • 18.
    Häggmark, Sören
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael F
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jensen, Steen M
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    ST-segment deviations during pacing-induced increased heart rate in patients without coronary artery disease.2005In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 25, no 4, p. 246-522Article in journal (Refereed)
    Abstract [en]

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

  • 19.
    Häggmark, Sören
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael F
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Vectorcardiographic ST deviations related to increased heart rate in the absence of ischemia in an experimental pig model.2006In: Journal of Electrocardiology, ISSN 0022-0736, E-ISSN 1532-8430, Vol. 39, no 2, p. 169-176Article in journal (Refereed)
    Abstract [en]

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

  • 20.
    Häggmark, Sören
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, Sebastian
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Contributions of myocardial ischemia and heart rate to ST segment changes in patients with or without coronary artery disease.2008In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 52, no 2, p. 219-228Article in journal (Refereed)
    Abstract [en]

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

  • 21.
    Häggmark, Sören
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences.
    Hohner, Per
    Östman, Margareta
    Friedman, Arnold
    Diamond, George
    Lowenstein, Edward
    Reiz, Sebastian
    Comparison of hemodynamic, electrocardigraphic, mechanical, and metabolic indicators of intraoperative myocardial ischemia in vascular surgical patients with coronary artery disease.1989In: Anesthesiology, ISSN 0003-3022, E-ISSN 1528-1175, Vol. 70, no 1, p. 19-25Article in journal (Refereed)
    Abstract [en]

    To compare mechanical, electrocardiographic, and metabolic indices of myocardial ischemia, the cardiokymogram (CKG), the V5 ECG, left anterior descending coronary artery territory lactate extraction, and pulmonary capillary wedge pressure (PCWP) were measured in 53 vascular surgical patients with coronary artery disease. Measurements were performed preoperatively and at four specific intraanesthetic intervals: after tracheal intubation, before surgery, and 10 and 30 min after incision. Measurements and sampling sequence took 5-7 min, and therapy for the probable cause of ischemia was instituted following completion of this sequence. Myocardial ischemia was defined as type II or III CKG, 0.1 mV or greater horizontal or downsloping depression of V5 ECG ST segment, 0.2 mV or greater elevation of V5 ECG ST segment, or myocardial lactate production. Thirty-nine patients (74%) had a total of 89 episodes of myocardial ischemia. Seventy-four episodes (83%) were detected by the CKG, 31 (44%) were evident on the ECG, and 13 (15%) by evidence of lactate production. The concordance among the indices of myocardial ischemia was poor. Patients with an abnormal preoperative ECG experienced a greater number of ischemic episodes (P less than 0.001). Elevation of PCWP or the presence of A-C or V-waves greater than 5 mmHg above the mean did not individually reflect ischemia reliably. Intraoperative myocardial ischemia is common in vascular surgical patients and is most sensitively detected by ventricular wall motion abnormality.

  • 22.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    On-line computerized vectorcardiography: influence of body position, heart rate, radiographic contrast fluid and myocardial ischemia1997In: Cardiology, Vol. 88, no 6, p. 576-84Article in journal (Refereed)
    Abstract [en]

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

  • 23.
    Jensen, Steen
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Karp, Kjell
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Clinical Physiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Assessment of myocardium at risk in pigs with single photon emission computed tomography and computerized vectorcardiography during transient coronary occlusion2000In: Scand Cardiovasc J, Vol. 34, no 2, p. 142-8Article in journal (Refereed)
    Abstract [en]

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

  • 24.
    Konrad, David
    et al.
    Karolinska Institutet, Anestesiologi och Intensivvård, Stockholm.
    Oldner, Anders
    Karolinska Institutet, Anestesiologi och Intensivvård, Stockholm.
    Wanecek, Michael
    Karolinska Institutet, Anestesiologi och Intensivvård, Stockholm.
    Rudehill, Anders
    Karolinska Institutet, Anestesiologi och Intensivvård, Stockholm.
    Weitzberg, Eddie
    Karolinska Institutet, Anestesiologi och Intensivvård, Stockholm.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Positive inotropic and negative lusitropic effects of endothelin receptor agonism in vivo.2005In: American Journal of Physiology, Heart and Circulatory Physiology, ISSN 0363-6135, Vol. 289, no 4, p. H1702-9Article in journal (Refereed)
    Abstract [en]

    The endothelin (ET) system is involved in the regulation of myocardial function in health as well as in several diseases, such as congestive heart failure, myocardial infarction, and septic myocardial depression. Conflicting results have been reported regarding the acute contractile properties of ET-1. We therefore investigated the effects of intracoronary infusions of ET-1 and of the selective ET(B) receptor-selective agonist sarafotoxin 6c with increasing doses in anesthetized pigs. Myocardial effects were measured through analysis of the left ventricular pressure-volume relationship. ET-1 elicited increases in the myocardial contractile status (end-systolic elastance value of 0.94 +/- 0.11 to 1.48 +/- 0.23 and preload recruitable stroke work value of 68.7 +/- 4.7 to 83.4 +/- 7.2) that appear to be mediated through ET(A) receptors, whereas impairment in left ventricular isovolumic relaxation (tau = 41.5 +/- 1.4 to 58.1 +/- 5.0 and t(1/2) = 23.0 +/- 0.7 to 30.9 +/- 2.6, where tau is the time constant for pressure decay and t(1/2) is the half-time for pressure decay) was ET(B) receptor dependent. In addition, intravenous administration of ET-1 impaired ventricular relaxation but had no effect on contractility. Intracoronary sarafotoxin 6c administration caused impairments in left ventricular relaxation (tau from 43.3 +/- 1.8 to 54.4 +/- 3.4) as well as coronary vasoconstriction. In conclusion, ET-1 elicits positive inotropic and negative lusitropic myocardial effects in a pig model, possibly resulting from ET(A) and ET(B) receptor activation, respectively.

  • 25.
    Nath, Sherdil
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Differential depressant and electrophysiologic cardiotoxicity of local anesthetics: an experimental study with special reference to lidocaine and bupivacaine1986In: Anesth Analg, Vol. 65, no 12, p. 1263-70Article in journal (Refereed)
    Abstract [en]

    In 15 pigs lidocaine and bupivacaine were injected into the left anterior descending (LAD) coronary artery to investigate the cardiotoxic effects of these drugs. Anesthesia was maintained by a continuous intravenous pentobarbital infusion and ventilation was controlled. Aortic, pulmonary arterial, right atrial, and left ventricular pressures, a standard 12 lead ECG, cardiac output, and great cardiac venous blood flow were recorded. The local anesthetics were administered at body temperature over approximately 10 sec in a random, crossover fashion at the following equipotent anesthetic doses: bupivacaine, 0.25, 0.5, 1, 2, and 4 mg; lidocaine, 1, 2, 4, 8, and 16 mg. The hemodynamic effects were short-lived, peaking about 5 sec after drug infusion. At the highest dose, both drugs decreased left ventricular dP/dT by 28% (P less than 0.001) and aortic blood pressure by 12% (lidocaine) and 8% (bupivacaine) (P less than 0.001 and P less than 0.01). Heart rate, cardiac output, and coronary venous blood flow did not change. Thus, the cardiodepressant ratio between the two drugs was comparable with their local anesthetic the two drugs was comparable with their local anesthetic potency ratio (bupivacaine/lidocaine, 4:1). Seven animals died in ventricular fibrillation within 1 min after 4 mg bupivacaine dose. All animals given 16 mg lidocaine survived. Ventricular fibrillation was preceded by progressive widening of the QRS complexes recorded over the area perfused by the LAD. The ECG changes after 16 mg lidocaine were of the same magnitude as those recorded after 1 mg bupivacaine. In five of the surviving animals 32 and 64 mg lidocaine were injected intracoronarily after termination of the crossover study.(ABSTRACT TRUNCATED AT 250 WORDS)

  • 26.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Marklund, Stefan
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Clinical chemistry.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    A closed-chest myocardial occlusion-reperfusion model in the pig: techniques, morbidity and mortality1992In: Eur Heart J, Vol. 13, no 9, p. 1282-9Article in journal (Refereed)
    Abstract [en]

    Extensive preparative surgery and lengthy experimentation may lead to high rate of complications and mortality in myocardial ischaemia studies. These problems are particularly common when pigs are used as the subject as they are prone to develop lethal ventricular arrhythmias. Here, a closed-chest model is presented, in which the trauma of major preparative surgery is avoided. One-hundred and twelve pentobarbital-anaesthetized, mechanically ventilated pigs were used. Coronary occlusion was produced by injection of a 2 mm diameter ball via a modified coronary angiography catheter. Reperfusion was induced by retraction of the ball via a thin filament attached to the ball. The amount of the myocardium at risk (MAR) was 8.23 +/- 2.41% (mean +/- SD) of the left plus right ventricular weight. It was possible to carry out scheduled 24 h experiments in 87 out of 93 animals (93.5%). Preparative mortality was 1.8% and 24 h mortality 6.5%. Ventricular fibrillation (VF) occurred during preparation in 3.6%, during coronary occlusion in 7.3% and during reperfusion in 5.0% of the animals. VF was significantly related to a large zone of MAR and insufficient premedication. Catheter- or ball-induced complications were found in 10.7%. Mortality and incidence of VF are considerably lower in this closed-chest model than in a previously reported open-chest pig preparation.

  • 27.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Marklund, Stefan
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Clinical chemistry.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Limitation of myocardial infarct size by superoxide dismutase as an adjunct to reperfusion after different durations of coronary occlusion in the pig1990In: Circ Res, Vol. 66, no 5, p. 1294-301Article in journal (Refereed)
    Abstract [en]

    Superoxide dismutase (SOD) has been documented to limit myocardial infarct size in the richly collateralized dog heart. This study was designed to explore this concept in a low-collateralized animal model. A blind, randomized, placebo-controlled protocol was used in 65 pentobarbital-anesthetized pigs subjected to closed-chest left anterior descending coronary artery occlusion for 30 (n = 22), 60 (n = 22), and 90 (n = 14) minutes followed by reperfusion up to 24 hours from the start of occlusion. Another seven control pigs were subjected to 24 hours of permanent occlusion. A total dose of 9 mg/kg bovine CuZn SOD was administered as a bolus injection immediately before reperfusion followed by a 1-hour infusion. Infarct size was assessed by tetrazolium staining. Myocardium at risk and collateral flow were determined by using cerium-141-labeled microspheres (15 microns) during the occlusion. After 30 minutes of occlusion, infarct sizes in placebo versus SOD-treated animals were 45.5 +/- 15.7% vs. 23.8 +/- 15.6% of myocardium at risk (p = 0.007). The corresponding values after 60 minutes of occlusion were 78.6 +/- 9.3% vs. 66.9 +/- 14.6% (p = 0.035). SOD administered after 90 minutes of occlusion did not limit infarct size (88.5 +/- 4.8% vs. 92.3 +/- 5.2%). Twenty-four hours of coronary occlusion resulted in infarction of 92.4 +/- 4.2% of myocardium at risk. (All values are mean +/- SD.) Ventricular fibrillation occurred in only nine pigs distributed equally between SOD and placebo. The results indicate that CuZn SOD has the potential to further improve the myocardial salvage established by reperfusion of an ischemic pig heart territory. However, the narrow time window for limiting infarct size in the pig by reperfusion is not much extended by SOD.

  • 28.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Marklund, Stefan
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Clinical chemistry.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Öberg, Agneta
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Clinical chemistry.
    Superoxide dismutase and catalase reduce infarct size in a porcine myocardial occlusion-reperfusion model1986In: J Mol Cell Cardiol, Vol. 18, no 10, p. 1077-84Article in journal (Refereed)
    Abstract [en]

    We investigated if superoxide dismutase and catalase could reduce myocardial infarct size in an open chest occlusion-reperfusion model. Thirty pigs were used for the experiment. The left anterior descending artery was ligated for 60 min followed by a 5 h reperfusion period. After randomisation and blinding the two enzymes or placebo were injected into the left atrium as a bolus immediately before and at the end of the occlusion and as a continuous infusion over the first hour of the reperfusion period. The total dose for each enzyme was 8 mg/kg bw. Tetrazolium staining was used to determine infarct size. The study code was not broken until all calculations and exclusions had been made. Nine animals died from intractable ventricular fibrillation, most commonly during the occlusion. Another three were excluded for technical reasons. We found that superoxide dismutase and catalase reduced infarct size in relation to myocardium at risk from a mean of 89% to 63% (P less than 0.01). Initial plasma half life for the two enzymes after the bolus infusions were calculated to be 30 min.

  • 29.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Pennert, Kjell
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Marklund, Stefan
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Clinical chemistry.
    Effects of reperfusion and superoxide dismutase on myocardial infarct size in a closed chest pig model1992In: Cardiovasc Res, Vol. 26, no 2, p. 170-8Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The aim was to study the effects on myocardial infarct size of reperfusion alone or of CuZn superoxide dismutase (SOD) as an adjunct to reperfusion. METHODS: Occlusion was induced in closed chest, pentobarbitone anaesthetised, mechanically ventilated pigs by injection of a 2 mm ball into a preselected coronary artery. Reperfusion was achieved by retraction of the ball via an attached filament. Twenty nine placebo treated and 25 SOD treated animals were subjected to 30 (n = 21), 60 (n = 21), and 90 (n = 12) min of coronary occlusion followed by reperfusion to 24 h; a control group of 24 pigs was subjected to a sustained occlusion for 24 h. Infarct size was assessed by tetrazolium staining and plasma creatine kinase (CK), aspartate aminotransferase (ASAT), and lactate dehydrogenase (LD). In the CuZn SOD group, 200 mg bovine CuZn SOD was given as a bolus intravenously immediately before reperfusion followed by a continuous infusion (100 mg) for 60 min. The size of the ischaemic myocardium at risk was measured from post mortem autoradiograms. RESULTS: Infarct size as percent of myocardium at risk was 46.0(SD 15.5)%, 80.1(9.9)%, and 88.9(5.0)% respectively in placebo animals with 30, 60, and 90 min occlusion, and 94.2(5.1)% in pigs with 24 h sustained occlusion. Compared to 24 h sustained occlusion, limitation of infarct size by reperfusion was only demonstrated in the 30 (p less than 0.001) and 60 min groups (p less than 0.001). Plasma values of CK, ASAT, and LD at 90 min post-reperfusion correlated closely with infarct size as assessed by tetrazolium staining and were related to occlusion duration. No myocardial salvage, as assessed by plasma ASAT, CK, or LD, was shown in the SOD treated groups. CONCLUSIONS: Early reperfusion resulted in myocardial salvage as assessed by tetrazolium staining and peak ASAT, CK, and LD at 90 min after the reperfusion. No limitation of infarct size by SOD could be demonstrated from analyses of plasma CK, ASAT, or LD.

  • 30.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Ischaemia and reperfusion induced transient QRS vector changes: relationship to size of the ischaemic territory1993In: Cardiovasc Res, Vol. 27, no 2, p. 327-33Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The aim was to investigate QRS vector changes during the first 30 min of coronary occlusion or the early phase of reperfusion with special reference to location and size of myocardium at risk. METHODS: 24 h experiments were performed in closed chest anaesthetised pigs. QRS vectors were studied by computerised vectorcardiography via Frank leads. Occlusion of the left anterior descending coronary artery followed by reperfusion was induced in 23 pigs and a sustained occlusion in 20 pigs: left anterior descending coronary artery in seven, right coronary artery in eight, and left circumflex coronary artery in five. Myocardium at risk was measured in postmortem autoradiograms. Eight animals were excluded. RESULTS: Four minutes after occlusion, QRS(mean) deviated towards the ischaemic region in 34/35 animals and returned thereafter at varying speeds. In half of the reperfused animals, deviation of QRS vectors towards the ischaemic territory was also observed during the first minutes of reperfusion. A paradoxical increase in QRS vector changes, "reperfusion peak", was recorded during the initial minutes of reperfusion in 12/19 animals. Maximum spatial QRS vector magnitude increased in all right coronary or left circumflex coronary occlusion animals compared to 6/25 in left anterior descending coronary occlusion animals. QRS vector difference, change in spatial QRS vector angle, and maximum change in QRS azimuth 4 min after occlusion correlated significantly with extent of myocardium at risk. CONCLUSIONS: Marked directional and quantitative QRS vector changes, with significant relation to size and location of myocardium at risk, were recorded during the initial minutes of ischaemia. The transient increase in QRS vector changes during the first minutes of reperfusion deserves further exploration as a new indicator of reperfusion.

  • 31.
    Näslund, Ulf
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, Sebastian
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Quantification of myocardium at risk and detection of reperfusion by dynamic vectorcardiographic ST segment monitoring in a pig occlusion-reperfusion model1993In: Cardiovasc Res, Vol. 27, no 12, p. 2170-8Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The aim was to investigate whether continuous computerized vectorcardiographic monitoring of absolute spatial ST vector magnitude (ST-VM) and spatial ST change vector magnitude (STC-VM) during coronary occlusion could be used to estimate the size of myocardium at risk; and also to test whether reperfusion could be distinguished from sustained occlusion by continuous monitoring of ST vector alterations. METHODS: Computerised vectorcardiographic monitoring via Frank leads was applied in a closed chest occlusion-reperfusion pig model. Coronary occlusion over 24 h was produced in 20 animals by injecting a 2 mm ball into the left anterior descending coronary artery (n = 7), the right coronary artery (n = 8), and the left circumflex coronary artery (n = 5). Another 31 pigs were reperfused by retraction of the ball after 30 (n = 10), 60 (n = 15), or 90 (n = 6) min of left anterior descending artery occlusion. The extent of the myocardium at risk was measured by autoradiography. RESULTS: Seven animals were excluded. Irrespective of occluded coronary artery the relative parameters STC-VM over the first 30 min of occlusion correlated closely with area at risk, that is, the mean STC-VM between 10 and 30 min of occlusion (r = 0.78 p < 0.001). The absolute parameter ST vector magnitude (ST-VM) did not reflect ischaemia in 16/44 animals and did not correlate significantly with area at risk. The weight of myocardium at risk (MAR) was predictable from STC-VM: MAR weight (measured) = 0.97 x MAR weight (predicted) + 0.26 (g), r = 0.81, p < 0.001. STC-VM decline rate, time to STC-VM plateau, and cumulated sum plots of STC-VM were all able to distinguish reliably between reperfused animals and those with permanent occlusion. A paradoxical increase in STC-VM - "reperfusion peak" - was detected in 17/31 (55%) of the animals. This phenomenon was related to large amount of myocardium at risk or to a long occlusion time. CONCLUSION: Dynamic vectorcardiographic ST monitoring provides adequate estimation of myocardium at risk and enables detection of reperfusion in experimental myocardial ischaemia.

  • 32.
    Reiz, S.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Bålfors, E.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Gustavsson, B.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nath, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Rydvall, A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Truedsson, H.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Effects of halothane on coronary haemodynamics and myocardial metabolism in patients with ischaemic heart disease and heart failure1982In: Acta Anaesthesiol Scand, Vol. 26, no 2, p. 133-8Article in journal (Refereed)
    Abstract [en]

    Halothane was administered at an end-tidal concentration of 1% to 10 patients with stable ischaemic heart disease and clinical and haemodymanic signs of moderate heart failure. Measurements of central haemodynamic variables, coronary sinus blood flow and oxygen, lactate and hypoxanthine balances over the myocardium were done before and at steady state during halothane anaesthesia. Halothane induced marked haemodynamic changes with decreases in mean arterial pressure (-43%), mean pulmonary arteriolar occlusion pressure (-42%), systemic vascular resistance (-31%), cardiac index (-20%) stoke volume index (-31%) and left and right stroke work indices (-62% and -55%, respectively). Heart rate and pulmonary vascular resistance did not change. Coronary sinus blood flow decreased in parallel with perfusion pressure, and myocardial oxygen consumption decreased (-40%), as did myocardial oxygen extraction. Rate pressure product and triple product correlated better with changes in myocardial oxygen consumption in the present subset of patients than in healthy volunteers during halothane anaesthesia. The findings suggest that halothane, through its systemic vasodilatory effect, unloads the failing left ventricle and that this peripheral action predominates over the direct cardiodepressant action of the agent. The combined findings of unchanged coronary vascular resistance, decreased myocardial oxygen extraction and absence of increasing or pathological levels of lactate and hypoxanthine in coronary sinus blood imply a direct dilatory effect of halothane on the coronary vasculature.

  • 33.
    Reiz, S.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Bålfors, E.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nath, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Rydvall, A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Truedsson, H.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Myocardial oxygen consumption and coronary haemodynamics during fentanyl-droperidol-nitrous oxide anaesthesia in patients with ischaemic heart disease1981In: Acta Anaesthesiol Scand, Vol. 25, no 3, p. 286-92Article in journal (Refereed)
    Abstract [en]

    Eight patients with stable ischaemic heart disease were investigated to determine the effects of fentanyl (15 micrograms/kg) - droperidol (150 micrograms/kg) - nitrous oxide (75%) anaesthesia, without concomitant fluid challenge, on myocardial oxygen consumption and lactate uptake, and central and coronary haemodynamics. Anaesthesia induced reductions in mean arterial pressure (--35%, P less than 0.01), systemic vascular resistance (--30%, P less than 0.01), left ventricular stroke work index (--50%, P less than 0.01) and total body oxygen consumption (--23%, P less than 0.01), with no changes in heart rate, cardiac output or mean pulmonary arteriolar occlusion pressure. Mixed venous oxygen content increased (P less than 0.05). Systemic vasodilatation, circulatory adaptation to an overall lower metabolic rate, and clinically negligible cardiodepression are the likely mechanisms behind the central haemodynamic response to this form of anaesthesia. Coronary sinus blood flow (measured by the continuous thermodilution technique) decreased (P less than 0.01) in parallel with the decrease in coronary perfusion pressure. Thus coronary vascular resistance remained unchanged. As expected from the haemodynamic findings, myocardial oxygen consumption decreased (--37%, P less than 0.01). Coronary sinus oxygen content and myocardial oxygen extraction did not change, nor was myocardial lactate uptake affected. No ST-T-segment depressions or dysrhythmias were recorded. These observations indicate that myocardial oxygenation was adequate in spite of the reduction in coronary perfusion pressure. There was poor correlation between changes in myocardial oxygen consumption and rate pressure product (R = 0.455) or triple produce (R - 0.375).

  • 34.
    Reiz, S.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Rydvall, A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Östman, M.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Beta-blockers and thoracic epidural analgesia. Cardioprotective and synergistic effects1982In: Acta Anaesthesiol Scand Suppl, Vol. 76, p. 54-61Article in journal (Refereed)
    Abstract [en]

    Seven groups of patients with and without hypertension or with ischaemic heart disease, treated with different beta blockers were investigated to study the circulatory effects of neurolept anaesthesia alone or combined with thoracic epidural analgesia from T4 to T12/L2 during abdominal surgery. The combination of thoracic epidural analgesia and neurolept anaesthesia in hypertensive subjects treated with non-cardioselective beta blockers induced slightly lower blood pressure than measured in similar patients on cardioselective beta blockers with neurolept anaesthesia only. Patients on non-selective beta blockers with intrinsic stimulatory activity (ISA) had higher blood pressure and heart rate after neurolept anaesthesia induction than patients on cardioselective blockers. During surgery, heart rate remained at a higher level in the patients treated with ISA blockers, whereas blood pressure increased to the same level as in patients with cardioselective blockers. Cardiovascular stability was, however, best maintained in the epidural group, where myocardial energy expenditure during maximal surgical stress was comparable to that in a group of healthy subjects with the same format of anaesthesia and significantly lower than in healthy subjects with neurolept anaesthesia alone. No circulatory side effects of the combination of thoracic epidural analgesia and beta blockade were seen. In patients with ischaemic heart disease, with or without non-selective beta blockade, similar haemodynamic changes were recorded following neurolept anaesthesia. During maximal surgical stress, unmasking of alpha adrenergic activity with marked rise in blood pressure was seen in the beta-blocked patients. Despite the more accelerated haemodynamic changes in the blocked patients, a lower increase in myocardial oxygen consumption was recorded compared with the non-blocked patients.(ABSTRACT TRUNCATED AT 250 WORDS)

  • 35.
    Reiz, S.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Rydvall, A.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Coronary haemodynamic effects of surgery during enflurane-nitrous oxide anaesthesia in patients with ischaemic heart disease1985In: Acta Anaesthesiol Scand, Vol. 29, no 1, p. 106-12Article in journal (Refereed)
    Abstract [en]

    The systemic and coronary haemodynamic effects of 1.5 MAC enflurane-nitrous oxide anaesthesia and abdominal surgery were investigated in nine patients with ischaemic heart disease. Anaesthesia decreased systemic blood pressure (-56%) by a combination of cardiodepression and peripheral vasodilation. A marked fall in myocardial oxygen extraction suggested a moderate coronary vasodilation. Surgery markedly increased the circulating levels of adrenaline and noradrenaline, manifested by increases in blood pressure (+76%) and systemic vascular resistance (+83%). Pulmonary capillary wedge pressure increased by 70% without any change in cardiac or stroke volume index, suggesting that the patients were performing at the horizontal part of their left ventricular function curve. Despite the marked rise in coronary perfusion pressure and a 62% increase in myocardial oxygen demand, coronary blood flow remained unaltered. This could be due either to coronary vasoconstriction overriding the normal coronary autoregulation or to an increase in coronary back pressure opposing the diastolic aortic pressure. When coronary blood flow could not increase to meet the demand for oxygen, the myocardium had to extract more oxygen to ensure appropriate oxygenation, demonstrating interference with coronary autoregulation. Surgery markedly increased myocardial extraction of adrenaline and noradrenaline. We could not find any relationship between myocardial adrenaline extraction and heart rate response to surgery or between myocardial noradrenaline extraction and changes in coronary blood flow, calculated coronary vascular resistance, incidence of myocardial ischaemia or cardiac dysrhythmias.

  • 36.
    Reiz, Sebastian
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nath, Sherdil
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Cardiotoxicity of ropivacaine--a new amide local anaesthetic agent1989In: Acta Anaesthesiol Scand, Vol. 33, no 2, p. 93-8Article in journal (Refereed)
    Abstract [en]

    Anaesthetically equipotent doses of lidocaine, bupivacaine and a new bupivacaine-like local anaesthetic agent, ropivacaine, were injected into the left anterior descending coronary artery of pentobarbital-anaesthetized pigs. The aim was to study the cardiotoxicity of ropivacaine in relation to the two other drugs. A random, crossover, dose response study design was used. The following doses of the drugs were administered: lidocaine (L): 1,2,4,8 and 16 mg, bupivacaine (B): 0.25, 0.5, 1,2 and 4 mg and ropivacaine (R): 0.33, 0.66 1.33, 2.66 and 5.33 mg. Systemic haemodynamics, left ventricular dP/dT and a 12-lead electrocardiogram were recorded continuously during the study period. The drugs depressed cardiac contractility in relation to their local anaesthetic potency on the isolated nerve-4:3:1 (B:R:L). The prolongation of the ECG QRS-interval was regarded as a measure of electrophysiologic toxicity. Comparable prolongation of the QRS-interval was recorded after 2 mg of bupivacaine, 4.5 mg of ropivacaine and 30 mg of lidocaine. Thus, the electrophysiological toxicity ratio was 15:6.7:1 (B:R:L). Provided local anaesthetic potency data can be extrapolated from the isolated nerve preparation to regional anaesthesia in humans, ropivacaine appears to provide a greater margin of safety than bupivacaine, if inadvertently injected into the venous circulation.

  • 37.
    Rydvall, A.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Nyhman, H.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Reiz, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Effects of enflurane on coronary haemodynamics in patients with ischaemic heart disease1984In: Acta Anaesthesiol Scand, Vol. 28, no 6, p. 690-5Article in journal (Refereed)
    Abstract [en]

    The effects of enflurane with and without nitrous oxide on coronary haemodynamics and myocardial oxygenation were investigated in 11 patients with generalised atherosclerotic disease. Enflurane decreased systemic blood pressure (-50%) mainly by systemic vasodilation (SVR -41%) and to a lesser degree by impairment of cardiac performance (CO -27%). A change from 1MAC enflurane-nitrogen-oxygen (70/30) to 1MAC enflurane-nitrous oxide-oxygen (70/30) decreased blood pressure and cardiac output further (-16% and -14%). Enflurane-nitrogen-oxygen decreased coronary blood flow (-29%) and perfusion pressure (-47%). Coronary vascular resistance fell (-20%) along with decreases in myocardial oxygen consumption and extraction (-40% and -16%). Regional coronary blood flow measurements in four of the patients revealed maldistribution of blood flow. During enflurane-nitrous oxide-oxygen, myocardial oxygen consumption and extraction decreased further (-29% and -12%) without change in coronary blood flow or resistance. Myocardial ischaemia was observed in four patients during enflurane-nitrogen. During enflurane-nitrous oxide, ischaemia disappeared in two of the previously ischaemic patients and appeared in two not previously ischaemic. The regional blood flow maldistribution was abolished with nitrous oxide. It is concluded that enflurane is a powerful coronary vasodilator and in this respect slightly less potent than isoflurane. Enflurane may induce myocardial ischaemia by redistributing coronary blood flow and/or by producing hypotension. Nitrous oxide added to enflurane depresses cardiac function and augments the coronary vasodilatory effect of enflurane to a level at which coronary blood flow becomes totally pressure dependent.

  • 38. Seeman‐Lodding, Helen
    et al.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jern, Christina
    Jern, Sverker
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Systemic levels and preportal organ release of tissue‐type plasminogen activator are enhanced by PEEP in the pig1999In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 43, no 6, p. 623-633Article in journal (Refereed)
  • 39. Seeman-Lodding, Helene
    et al.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jern, Christina
    Jern, Sverker
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Anesthesia and surgery influences regional net release and uptake rates of tissue-type plasminogen activator. An experimental study in the intact pig1997In: Acta Anaesthesiol Scand Suppl, Vol. 110, p. 151-3Article in journal (Refereed)
  • 40. Seeman-Lodding, Helene
    et al.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jern, Christina
    Jern, Sverker
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Aortic cross-clamping influences regional net release and uptake rates of tissue-type plasminogen activator in pigs1997In: Acta Anaesthesiol Scand, Vol. 41, no 9, p. 1114-23Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The key regulator of intravascular fibrinolysis, tissue-type plasminogen activator (t-PA), is released from a dynamic endothelial storage pool. The aim of the study was to investigate regional t-PA net release and uptake rates in response to infra-renal aortic cross-clamping (AXC) and declamping (DC). METHODS: Anesthetized pigs were studied during 5 min of AXC, followed by a 35-min declamping (DC) period. Arterio-venous concentration gradients of total and active t-PA, as well as respective plasma flows, were simultaneously obtained across the preportal, hepatic, coronary and pulmonary vascular beds. Plasma levels of total t-PA (ELISA with purified porcine t-PA as standard), and active t-PA (spectrophotometric functional assay) were determined. RESULTS: Prior to AXC, we found a high net release rate of total t-PA across the preportal vascular bed (1700 ng.min-1 P < 0.001), and a high hepatic net uptake (4900 ng.min-1, P < 0.001), while coronary and pulmonary t-PA net fluxes were small and variable. AXC per se did not induce significant alterations in net fluxes of t-PA. Following DC, preportal and coronary net releases of total t-PA increased (to 2900 ng.min-1 and 60 ng.min-1, respectively). Despite an increase in hepatic net uptake of total t-PA (to 6100 ng.min-1) after DC, a significant increase in hepatic venous total t-PA occurred. CONCLUSIONS: The release and uptake of t-PA is indicated to be dynamic and organ-specific. DC induces an acute profibrinolytic reaction in preportal organs. The high hepatic t-PA uptake capacity restricts preportal profibrinolytic events to affect the systemic circulation.

  • 41. Sellgren, Johan
    et al.
    Söderstrom, Stefan
    Johansson, Göran
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Biber, Björn
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Pontén, Johan
    Preload changes by positive pressure ventilation can be used for assessment of left ventricular systolic function2003In: Acta Anaesthesiol Scand, Vol. 47, no 5, p. 541-8Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Assessment of preload independent left ventricular function with conductance volumetry is traditionally accomplished by inflating a balloon in the inferior caval vein. Our aim was to investigate if a similar change in preload could be achieved by positive pressure ventilation with large tidal volume. METHODS: Conductance volumetry generating left ventricular pressure-volume loops was used in seven pentobarbital-anesthetized pigs. Changes in preload recruitable stroke work were studied, comparing the effects of inferior vena cava occlusion (IVCO) or large tidal volume (LTV). Cardiodepression was induced by halothane anesthesia and halothane + phenylephrine, and stimulation by epinephrine infusion. RESULTS: Although the decreasis in left ventricular end diastolic volume was slightly less with LTV (16.5 +/- 1.7 ml, mean +/- SEM) than with IVCO (22.4 +/- 1.7 ml) (P < 0.0001) the PRSW-slopes showed a high degree of correlation (r=0.80, P < 0.0001). Although peak tracheal pressures increased significantly to 27.8 +/- 0.9 mmHg during LTV, esophageal pressures (used as an indicator of pericardial pressure) were unchanged. CONCLUSIONS: Positive pressure ventilation with LTV is similar to IVCO in creating transient changes in preload, necessary for assessment of left ventricular systolic function. This observation was valid also during drug-induced cardiac depression and stimulation. The preload recruitable stroke work used for this validation was shown to be a reliable and stable method.

  • 42. Sundeman, Henrik
    et al.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Broomé, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    The effects of desflurane on cardiac function as measured by conductance volumetry in swine1998In: Anesth Analg, Vol. 87, no 3, p. 522-8Article in journal (Refereed)
    Abstract [en]

    The purpose of the investigation was to assess the effects of desflurane (DES) on left ventricular heart function during basal barbiturate anesthesia in a closed-pericardium, closed-chest acute swine model. The study was performed in 11 normoventilated adult pigs. Hemodynamic measurements were obtained using arterial, central venous, and pulmonary artery catheters, as well as a conductance volumetry and tip manometry catheter placed in the left ventricle. Hemodynamic measurements were recorded during basal pentobarbital anesthesia and with the addition of 1%, 2%, 4%, and 6% DES. DES dose-dependently decreased mean arterial pressure, systemic vascular resistance, left ventricular end-systolic pressure, dP/dtMAX and dP/dtMIN. At doses >1%, decreases in CO, stroke volume, ejection fraction, end-systolic elastance, preload recruitable stroke work, preload adjusted maximal power, and peak filling rate were observed. Heart rate decreased at 4% and 6% DES. Isovolumetric relaxation time increased only at 6% DES. We conclude that smaller doses of DES have a significant cardiodepressive effect in the setting of barbiturate infusion, as measured by conductance volumetry. IMPLICATIONS: Desflurane, in very small doses, depressed cardiac function during pentobarbital anesthesia with ketamine and benzodiazepine premedication in swine, as assessed by conductance volumetry and left ventricular pressure and volume relationship analysis. These results suggest that desflurane, in combination with certain anesthetics, can be cardiodepressive even in very small doses.

  • 43. Sundeman, Henrik
    et al.
    Åneman, Anders
    Broomé, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Haney, Michael
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Biber, Björn
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Effects of desflurane on the pig intestinal circulation during hypotension1999In: Acta Anaesthesiol Scand, Vol. 43, no 10, p. 1069-77Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The aim of the present study was to analyze the perfusion pressure dependency for the splanchnic vascular effects of desflurane (DES). METHODS: We measured portal blood flow (QPORT, perivascular ultrasound) and jejunal mucosal perfusion (JMP; laser Doppler) in pentobarbital-anesthetized pigs (n=10). Experimentally, decreases in mean arterial pressure (MAP) were produced by pericardial infusions of dextran. The protocol included sets of measurements at incremental doses of DES (1, 2, 4 and 6%) prior to and during pericardial infusions. RESULTS: Although QPORT and JMP decreased significantly during pericardial infusions, DES, irrespective of dose, did not reduce QPORT until MAP had decreased below 65-70 mm Hg. In higher MAP ranges, vasodilation in pre-portal tissues was powerful enough to maintain QPORT in spite of concurrent decreases in driving arterial pressure, as produced by either DES or pericardial infusion, or by a combination of both. We found no effects of DES on JMP even at very low MAP (about 40 mm Hg during pericardial infusion), indicating that the normal physiological response of the small intestine to redistribute blood flow from deeper to more superficial layers during hypotension was unimpaired by DES. CONCLUSIONS: Our data suggest a wide dose-tolerability of DES as regards the splanchnic circulation during hypotensive states.

  • 44.
    Svenmarker, S.
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Jansson, E.
    Lindholm, R.
    Appelblad, M.
    Sandström, E.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Åberg, T.
    Use of heparin-bonded circuits in cardiopulmonary bypass improves clinical outcome2002In: Scand Cardiovasc J, Vol. 36, no 4, p. 241-6Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: The use of heparin-coated surfaces in cardiopulmonary bypass has been shown to decrease the inflammatory response imposed by the contact between blood and artificial surfaces. One would expect this reaction to improve clinical outcome. However, this has been difficult to verify. This investigation is based on an aggregation of two randomized studies from our institution and highlights possible effects of heparin coating on a number of clinically oriented parameters. DESIGN: Departmental analysis of patients subjected to coronary artery bypass surgery using heparin-coated circuits. Cardiopulmonary bypass was employed using either the Carmeda or Duraflo heparin coatings compared with a control. The systemic heparin dose was reduced in the heparin-coated groups (ACT > 250 s) vs control group patients (ACT > 480 s). The effects of heparin coating related to clinical outcome were studied. RESULTS: The use of heparin-coated circuits reduced the mean length of stay in hospital from 7.8 +/- 2.5 to 7.3 +/- 1.8 days (p = 0.040) and postoperative ventilation time from 9.7 +/- 9.2 to 8.2 +/- 8.5 h (p = 0.018), blood loss 8 h post surgery from 676 +/- 385 to 540 +/- 245 ml (p = 0.001), individual perioperative change of haemoglobin loss (p = 0.001), leukocyte count (p = 0.000) and creatinine elevation (p = 0.000), proportion of patients exposed to allogenous blood transfusions 39.2 vs 23.9% (p = 0.001), postoperative coagulation disturbances 4.4 vs 0.4% (p = 0.006), postoperative deviations from the normal postoperative course 47.2 vs 36.7% (p = 0.035), neurological deviations 9.4 vs 3.9% (p = 0.021) and atrial fibrillation 26.4 vs 18.0% (p = 0.041). No effects were found with respect to perioperative platelet count, postoperative fever reaction and 5-year survival. CONCLUSION: Based on several indicators, the use of heparin coating in cardiopulmonary bypass is associated with improved clinical results.

  • 45.
    Svenmarker, S.
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Sandström, E.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Karlsson, T.
    Häggmark, S.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Jansson, E.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Appelblad, M.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Lindholm, R.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Åberg, T.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Neurological and general outcome in low-risk coronary artery bypass patients using heparin coated circuits2001In: European Journal of Cardio-Thoracic Surgery, ISSN 1010-7940, E-ISSN 1873-734X, Vol. 19, no 1, p. 47-53Article in journal (Refereed)
    Abstract [en]

    Objective: The clinical significance of heparin coating in cardiopulmonary bypass has previously been investigated. However, few studies have addressed the possible influence on brain function and memory disturbances.

    Methods: Three hundred low-risk patients exposed to coronary bypass surgery were randomised into three groups according to type of heparin coating: Carmeda Bioactive Surface, Baxter Duraflo II and a control group. Outcome was determined from a number of clinically oriented parameters, including a detailed registry of postoperative deviations from the normal postoperative course. Brain damage was assessed through S100 release and memory tests, including a questionnaire follow-up.

    Results: Clinical outcome was similar for all groups. Blood loss (Duraflo only), transfusion requirements and postoperative creatinine elevation were reduced in the heparin-coated groups. A lower incidence of atrial fibrillation was noted in the Duraflo group. Heparin coating did not uniformly attenuate the release of S100 or the degree of memory impairment.

    Conclusions: Cardiopulmonary bypass (CPB) with heparin coating and a reduced dose of heparin seems to be safe. Clinical outcome and neurological injury seem not to be associated with type of heparin coating used for CPB. However, blood loss and transfusion requirements may be reduced.

  • 46.
    Svenmarker, Staffan
    et al.
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Appelblad, Micael
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Surgery.
    Jansson, Erica
    Häggmark, Sören
    Measurement of the activated clotting time during cardiopulmonary bypass: differences between Hemotec ACT and Hemochron Jr apparatus.2004In: Perfusion, ISSN 0267-6591, Vol. 19, no 5, p. 289-94Article in journal (Refereed)
  • 47.
    Svenmarker, Staffan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Serum markers are not reliable measures of renal function in conjunction with cardiopulmonary bypass2011In: Interactive Cardiovascular and Thoracic Surgery, ISSN 1569-9293, E-ISSN 1569-9285, Vol. 12, no 5, p. 713-717Article in journal (Refereed)
    Abstract [en]

    The present study explored the influence of haemodilution on estimates of the glomerular filtration rate (GFR) in conjunction with cardiopulmonary bypass (CPB) and cardiac surgery. Ninety-eight patients (n = 98) undergoing coronary artery bypass grafting with the aid of CPB were examined. The serum concentration of cystatin C and creatinine was analysed prior to surgery, after completion of CPB and in the intensive care the day after surgery. The estimated GFR was calculated using standard equations based on the serum concentration of cystatin C and creatinine. It was found that haemodilution induced by CPB had significant effects on the estimated GFR. For cystatin C, the GFR increased by 50.5 ± 2.5 ml/min (P = 0.000) and for creatinine based GFR with 22.5 ± 0.9 ml/min (P = 0.000) using the 4-variable modification of diet renal disease formula and with 22.1 ± 0.93 ml/min (P = 0.000) for the Cockcroft-Gault formula, respectively. Similar effects of haemodilution on GFR were also detected postoperatively. Haemodilution induced by CPB may therefore significantly overestimate the renal function as indicated by GFR based on serum markers.

  • 48.
    Svenmarker, Staffan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Hultin, Magnus
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Static blood-flow control during cardiopulmonary bypass is a compromise of oxygen delivery2009In: European Journal of Cardio-Thoracic Surgery, ISSN 1010-7940, E-ISSN 1873-734X, Vol. 37, no 1, p. 218-222Article in journal (Refereed)
    Abstract [en]

    Background: Blood-flow control during cardiopulmonary bypass (CPB) is by tradition based on the patient's body surface area. Emergence of new techniques enables dynamic blood-flow control based on online measurement of venous oxygen saturation and oxygen consumption. Present investigation aimed to compare static versus dynamic blood-flow control with respect to use of oxygen and effects upon organ function. Methods: In this study, 100 coronary-artery-bypass surgical patients were prospectively randomised to static or dynamic hypothermic blood-flow control during CPB. In the static group, pump flow was set to 2.4 (litres per minute) times the patient's body surface area (m(2)) throughout the procedure. Pump flow in the dynamic group was varied according to the reading of the venous oxygen saturation and maintained at >75%. CPB-specific information was collected online. Blood samples were collected for analysis of haemoglobin, lactate, amylase, creatinine and C-reactive protein: pre-CPB, at weaning from CPB and on day 1 postoperatively. Results: Randomisation formed two uniform groups. Choice of static or dynamic blood-flow control during CPB had no significant effects on organ function as judged by lactate, amylase or creatinine levels. On increasing oxygen demand, oxygen balance was maintained by increasing venous oxygen extraction rates in the static flow mode and by increasing the pump flow rate in the dynamic group. Conclusions: Independent of the blood-flow control mode, oxygen balance remained preserved. However, the dynamic mode provided higher oxygen delivery, which may increase margins of safety and protection of organ function.

  • 49. Svenmarker, Staffan
    et al.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    Ostman, Margareta
    Umeå University, Faculty of Medicine, Surgical and Perioperative Sciences, Anesthesiology and Intensive Care.
    What is a normal lactate level during cardiopulmonary bypass?2006In: Scand Cardiovasc J, ISSN 1401-7431, Vol. 40, no 5, p. 305-11Article in journal (Refereed)
  • 50.
    Svenmarker, Staffan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Häggmark, Sören
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Östman, Margareta
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Holmgren, Anders
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences.
    Näslund, Ulf
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Central venous oxygen saturation during cardiopulmonary bypass predicts 3-year survival2013In: Interactive Cardiovascular and Thoracic Surgery, ISSN 1569-9293, E-ISSN 1569-9285, Vol. 16, no 1, p. 21-26Article in journal (Refereed)
    Abstract [en]

    Long-term survival after cardiac surgery is determined by a number of different risk factors. Central venous oxygen saturation (SvO2) measures the balance between oxygen delivery and demand. SvO2 levels in the intensive care situation are reported to be associated with patient outcome. The present report explores the connection between SvO2 during cardiopulmonary bypass (CPB) and survival after cardiac surgery. Retrospective analysis of one thousand consecutive cardiac surgical patients was undertaken. SvO2 during CPB was monitored online. Registry data combining specific risk factors with SvO2 were selected for Kaplan-Meier and Cox regression analysis to examine the influence on 30-day and 3-year survivals. Nine-hundred and thirty-two patient records were eligible for analysis. SvO2 below 75% during CPB was associated with significantly shorter 30-day and 3-year survivals. Based on Kaplan-Meier statistics, the survival rate decreased by 3.1% (98.1-95.0), P = 0.011 and 6.1% (92.7-86.6), P = 0.003, respectively. The influence of SvO2 on 3-year survival remained statistically significant after controlling for a series of risk factors in the Cox regression analysis. Patients with SvO2 < 75% carried a 2-fold (odds ratio 2.1) increased relative risk of shortened 3-year survival (P = 0.003). Other risk factors statistically significantly associated with 3-year survival were age, gender, duration of CPB, blood temperature, hypertension, haematocrit and type of surgical procedure. We report decreased 30-day and 3-year survival expectancy for patients experiencing SvO2 lower than 75% during CPB.

12 1 - 50 of 53
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf