The influence of propofol and midazolam/halothane anesthesia on hepatic SvO2 and gastric mucosal pH during cardiopulmonary bypass.
OBJECTIVE
Because propofol is known to reduce vascular resistance, the objective of this study was to compare the indices of hepatosplanchnic circulation and oxygenation during cardiopulmonary bypass (CPB) in patients anesthetized with either propofol or midazolam/halothane.


METHODS
A prospective, randomized, nonblinded study.


METHODS
A university hospital.


METHODS
Twenty patients undergoing cardiac surgery with CPB.


METHODS
Nine patients were anesthetized with propofol/fentanyl/pancuronium and 11 patients were anesthetized with midazolam/halothane/fentanyl/pancuronium. All patients had a nasogastric tonometer tube and two fiberoptic thermodilution catheters inserted; one in the pulmonary artery and one in the upper right hepatic vein. During bypass, SvO2s were measured from the venous line of the heart-lung machine.


RESULTS
Gastric mucosal pH (pHi) was measured prebypass, 30 minutes after the start of CPB, and just before weaning off CPB. Hepatic SvO2 (HSvO2) values were recorded every 5 minutes. The pH gap was less at 30 minutes of hypothermic CPB in the propofol group. In the midazolam/halothane group, the HSvO2 decreased after the start of rewarming, whereas in the propofol group the values remained almost at the prebypass levels. At the end of rewarming, the HSvO2 was almost identical in the two groups.


CONCLUSIONS
Propofol preserved the HSvO2 during CPB and produced a more optimal relationship between the hepatosplanchnic blood flow and oxygen consumption.
Department of Anaesthesia, Skejby Hospital, Aarhus, Denmark.
C L
CL
Christiansen
P
P
Ahlburg
C J
CJ
Jakobsen
E B
EB
Andresen
P K
PK
Paulsen
D000759:Adjuvants, Anesthesia / Q000008:administration & dosage / Q000494:pharmacology*; D000368:Aged; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000494:pharmacology*; D018686:Anesthetics, Intravenous / Q000008:administration & dosage / Q000494:pharmacology*; D002315:Cardiopulmonary Bypass; D005283:Fentanyl / Q000008:administration & dosage; D005500:Follow-Up Studies; D005753:Gastric Mucosa / Q000187:drug effects* / Q000502:physiology; D006221:Halothane / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007036:Hypothermia, Induced; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008102:Liver Circulation / Q000187:drug effects; D008297:Male; D008874:Midazolam / Q000008:administration & dosage / Q000494:pharmacology*; D008875:Middle Aged; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage; D010101:Oxygen Consumption / Q000187:drug effects*; D010197:Pancuronium / Q000008:administration & dosage; D011312:Pressure; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D011446:Prospective Studies; D017694:Rewarming; D013152:Splanchnic Circulation / Q000187:drug effects; D013815:Thermodilution; D014655:Vascular Resistance / Q000187:drug effects
D000759:Adjuvants, Anesthesia; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D003473:Neuromuscular Nondepolarizing Agents; D010197:Pancuronium; D008874:Midazolam; D005283:Fentanyl; D006221:Halothane; D015742:Propofol