Hepatosplanchnic oxygenation is better preserved during mild hypothermic than during normothermic cardiopulmonary bypass.
OBJECTIVE
To assess and compare the effects of normothermic and mild hypothermic cardiopulmonary bypass (CPB) on hepatosplanchnic oxygenation.


METHODS
We studied 14 patients scheduled for elective coronary artery bypass graft surgery who underwent normothermic (>35 degrees C; group I, n=7) or mild hypothermic (32 degrees C; group II, n=7) CPB. After induction of anesthesia, a hepatic venous catheter was inserted into the right hepatic vein to monitor hepatic venous oxygen saturation (ShvO(2)) and hepatosplanchnic blood flow by a constant infusion technique that uses indocyanine green.


RESULTS
The ShvO(2) decreased from a baseline value in both groups during CPB and was significantly lower at ten minutes and 60 min after the onset of CPB in group I (39.5 +/- 16.2% and 40.1 +/- 9.8%, respectively) than in group II (61.1 +/- 16.2% and 61.0 +/- 17.9%, respectively; P <0.05). During CPB, the hepatosplanchnic oxygen extraction ratio was significantly higher in group I than in group II (44.0 +/- 7.2% vs 28.7 +/- 13.1%; P <0.05).


CONCLUSIONS
Hepatosplanchnic oxygenation was better preserved during mild hypothermic CPB than during normothermic CPB.
Okano
N
N
Department of Anesthesiology, Saitama Cardiovascular and Pulmonary Center, Saitama, Japan. richard@ka2.so-net.ne.jp
Hiraoka
H
H
Owada
R
R
Fujita
N
N
Kadoi
Y
Y
Saito
S
S
Goto
F
F
Morita
T
T
D002315:Cardiopulmonary Bypass; D001026:Coronary Artery Bypass; D006503:Hepatic Veins / Q000378:metabolism*; D006801:Humans; D007036:Hypothermia, Induced; D019344:Lactic Acid / Q000378:metabolism; D008102:Liver Circulation; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D013152:Splanchnic Circulation
D019344:Lactic Acid; D010100:Oxygen