Hepatic Function in Hemorrhagic Shock.

摘要

For the wounded soldier in combat, the time between his injury and treatment can be quite long and variable depending on the combat circumstance. The duration and severity of this hypotensive period are critical factors in determining his responsiveness to resuscitative efforts when aid does arrive. Due to the venous nature of the bulk of its blood flow, the liver is particularly susceptible to decreases in its blood flow and has been found to suffer high energy phosphate depletion relatively early in the course of hemorrhagic shock, and thus metabolic anomalies in this organ are especially relevant to the pathogenesis of the shock state. We have explored the effects of graded hypotension and isobaric hemorrhagic hypotension on hepatic oxygen delivery, defined by portal flow, hepatic tissue PO2 and arterial B-hydroxybutyrate/acetoacetate ratio measurements and function as assessed specifically by ethanol clearance. The results show that the B-hydroxybutyrate/acetoacetate ratio and the lactate/pyruvate ratios are equivalent in their indication of the hepatic aerobic to anaerobic transition within the fed and fasted groups but the absolute values of the ratio attained in this transition were significantly different although hepatic high energy phosphate status was equivalent. Due to these nutritional effects, single point determinations will have little value in evaluating hepatic oxygenation state during hypotension but may be valuable if followed serially. Hepatic clearance of ethanol was decreased proportionately with decreases in blood pressure down to 60 mm Hg and hepatic PO2 values <2 mm Hg where