1997 Volume 4 Issue 2 Pages 111-116
The arterial ketone body ratio (AKBR: arterial acetoacetate/β-hydroxybutyrate ratio) reflects the hepatic mitochondrial redox potential. It is frequently measured to evaluate hepatic dysfunction and multiple systems organ failure. We compared AKBR to the hepatic venous ketone body ratio (HKBR) to carify the doubt which exist as to whether AKBR really represents the ketone body ratio in hepatic venous blood.
This study was approved by our institutional review board and informed consents was obtained from thirteen consecutive patients undergoing hepatic resection surgery. After anesthetic induction, a radial arterial cannula was placed and 7.5-Fr fiberoptic catheters (OpticathModel P7110-EH, Oximetrix) were inserted into the pulmonary artery and the hepatic vein. Anesthesia was maintained with nitrous oxide and oxygen with isoflurane. We measured acetoacetate and β-hydroxybutyrate in each patient at one hour intervals while hepatic venous hemoglobin oxygen saturation was stable for a total of 80 sampling points. The results were evaluated with linear regression analysis and a p value of 0.05 or less was considered significant.
AKBR was significantly correlated to HKBR (r=0.880 (p<0.01), where AKBR=0.596×HKBR+0.119). On the linear regression line, HKBR was smaller than AKBR when AKBR was below 0.29, HKBR was larger than AKBR when AKBR was above 0.29. These results show that, the differences between HKBR and AKBR largely depend on the value of HKBR. The differences may be related to the ratio in which hepatic venous blood mixes with inferior vena cava blood. It is also possible that the differences were related to the clearance of ketone bodies which may vary depending on the value of HKBR.
These results were obtained during liver resection surgery, but may be applicable in general for the clinical evaluation of liver dysfunction associated with multiple systems organ failure.
