Role of hypotension in brain-death associated impairment of liver microcirculation and viability

Hypotension in brain-dead organ donors is considered a determinant factor o f graft viability. The aim of this study was to elucidate the role of hypot ension in brain-death associated impairment of hepatic microcirculation and function. Male Sprague-Dawley rats with an intracranial balloon were used. Group I (n = 7) served as sham controls. In group ZI (n = 7) brain death w as induced through inflation of an intracranial balloon. In group III (n = 7) hypotension without brain death was induced by means of pentobarbital. I n group II, a steep rise of arterial pressure was followed by a fall to a l ower level (P < 0.01, vs. group I). Also in group III arterial pressure was lower (P < 0.01, vs. group I). In group II, bile production was diminished (P < 0.05). Impaired sinusoidal perfusion (P < 0.01) and enhanced leukocyt e endothelium interaction (P < 0.05) were documented in hepatic microvascul ature. Electron microscopic analysis revealed vacuolization of hepatocytes; these changes were not observed in group III. Brain death induces specific changes of liver microcirculation, function and histomorphology. Independe nt of associated hypotension, brain death per se impairs donor liver graft quality.