Hepatic circulation during nonpulsatile cardiopulmonary bypass.
The arterial ketone body ratio, which reflects the hepatic mitochondrial redox potential (NAD+/NADH), decreases markedly during cardiopulmonary bypass (CPB). One of the reasons for arterial ketone body ratio reduction may be hepatic hypoperfusion during CPB. To evaluate the hepatic circulation under nonpulsatile CPB, the authors used color Doppler ultrasonography to measure the portal venous flow (PVF) in 24 adult patients before, during (aortic clamping and rewarming period), and after CPB. Nonpulsatile hypothermic CPB was performed at a flow rate of 2.4 L/min/m2. PVF was calculated from the product of mean flow velocity and cross-sectional area of the portal vein. PVF was maintained during CPB at 0.44 +/- 0.13 and at 0.54 +/- 0.18 L/min/m2. PVF (%) in relation to systemic blood flow was obtained by calculating PVF/CI or PVF/PI, where CI is the cardiac index and PI is the perfusion index. PVF (%) before, during, and after CPB was 18.3 +/- 9.3, 18.5 +/- 5.5, and 17.4 +/- 6.7%, respectively. In conclusion, PVF was maintained during nonpulsatile CPB at a flow rate of 2.4 L/min/m2 and depended upon systemic blood flow.
Yamada
T
T
Department of Cardiovascular Surgery, Kyoto University Faculty of Medicine, Japan.
Nomoto
S
S
Aota
M
M
Nishimura
K
K
Matsuda
K
K
Ban
T
T
D000328:Adult; D000368:Aged; D000818:Animals; D002315:Cardiopulmonary Bypass / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D007657:Ketone Bodies / Q000097:blood; D008102:Liver Circulation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D012212:Rheology; D018615:Ultrasonography, Doppler, Color
D007657:Ketone Bodies