Changes in the hepatic oxygenation state during hemorrhage and following epinephrine or dextran infusion as assessed by near-infrared spectroscopy
Kitai, T.; Tanaka, A.; Tokuka, A.; Tanaka, K.; Yamaoka, Y.; Ozawa, K.; Hirao, K.
Circulatory Shock 41(3): 197-205
1993
ISSN/ISBN: 0092-6213 PMID: 7505728 Document Number: 414171
Changes in the hepatic oxygenation state of rabbits during hemorrhage and subsequent epinephrine (n = 6) or dextran infusion (n = 6) were assessed by tissue near-infrared spectroscopy. Oxygen saturation of hemoglobin in the liver (hepatic SO-2), and redox transition of cytochrome aa-3 were analyzed by applying multicomponent analysis to the absorption spectrum of the liver. Hepatic SO-2, representing extracellular oxygenation state, decreased from 62.4 +- 2.7% (mean +- SEM) to 21.1 +- 7.3% after bleeding. It increased to 31.8 +- 6.6% after epinephrine infusion, but returned to near-control levels after dextran infusion. Intracellular oxygenation state as assessed by the changes in the oxidized and reduced forms of cytochrome aa-3 was impaired after bleeding, and remained as such even after epinephrine infusion. By contrast, it was normalized to near control levels after dextran infusion. Changes in the difference of hepatic SO-2 and hepatic venous SO-2 suggested that the intrahepatic blood flow was more heterogeneously distributed after bleeding, but that the heterogeneity of microcirculation was rather diminished after epinephrine infusion.