Effects of levosimendan on indocyanine green plasma disappearance rate and the gastric mucosal-arterial pCO2 gradient in abdominal aortic aneurysm surgery.
BACKGROUND
Levosimendan has a dual mechanism of action: it improves myocardial contractility and causes vasodilatation without increasing myocardial oxygen demand. In a laboratory setting, it selectively increases gastric mucosal oxygenation in particular and splanchnic perfusion in general. The aim of our study was to describe the effects of levosimendan on systemic and splanchnic circulation during and after abdominal aortic surgery.


METHODS
Twenty abdominal aortic aneurysm surgery patients were randomized to receive either levosimendan (n=10) or placebo (n=10) in a double-blinded manner. Both the mode of anaesthesia and the surgical procedures were performed according to the local guidelines. Automatic gas tonometry was used to measure the gastric mucosal partial pressure of carbon dioxide. Systemic indocyanine green clearance plasma disappearance rate (ICG-PDR) was used to estimate the total splanchnic blood flow.


RESULTS
The immediate post-operative recovery was uneventful in the two groups with a comparable, overnight length of stay in the intensive care unit. Cumulative doses of additional vasoactive drugs were comparable between the groups, with a tendency towards a higher cumulative dose of noradrenaline in the levosimendan group. After aortic clamping, the cardiac index was higher [4(3.8-4.7) l/min/m(2) vs. 2.6(2.3-3.6) l/min/m(2); P<0.05] and the gastric mucosal-arterial pCO(2) gradient was lower in levosimendan-treated patients [0.9(0.6-1.2) kPa vs. 1.7(1.2-2.1) kPa; (P<0.05)]. However, the total splanchnic blood flow, estimated by ICG-PDR, was comparable [29(21-29)% vs. 20(19-25)%; NS]. Organ dysfunction scores (sequential organ dysfunction assessment) were similar between the groups on the fifth post-operative day.


CONCLUSIONS
Levosimendan favours gastric perfusion but appears not to have a major effect on total splanchnic perfusion in patients undergoing an elective aortic aneurysm operation.
Leppikangas
H
H
Critical Care Medicine Research Group, Department of Intensive Care, Tampere University Hospital, Tampere, Finland. heli.leppikangas@pshp.fi
Tenhunen
J J
JJ
Lindgren
L
L
Salenius
J-P
JP
Ruokonen
E
E
D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000378:metabolism / Q000601:surgery*; D001775:Blood Circulation / Q000187:drug effects*; D002245:Carbon Dioxide / Q000032:analysis; D004396:Coloring Agents / Q000493:pharmacokinetics*; D004311:Double-Blind Method; D005260:Female; D005753:Gastric Mucosa / Q000187:drug effects; D006801:Humans; D006835:Hydrazones / Q000494:pharmacology*; D007208:Indocyanine Green / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000627:therapeutic use; D011724:Pyridazines / Q000494:pharmacology*; D000077464:Simendan; D013152:Splanchnic Circulation / Q000187:drug effects; D013997:Time Factors; D016896:Treatment Outcome; D014662:Vasoconstrictor Agents / Q000627:therapeutic use; D014665:Vasodilator Agents / Q000494:pharmacology*
D004396:Coloring Agents; D006835:Hydrazones; D011724:Pyridazines; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D002245:Carbon Dioxide; D000077464:Simendan; D007208:Indocyanine Green; D009638:Norepinephrine