Changes in hepatic microcirculation and histomorphology in brain-dead organ donors: An experimental study in rats

Objective: To assess the effect of brain death on hormonal homeostasis, hep atic microcirculation, and histomorphology in organ donors. Design: Prospective randomised experimental study Setting: Institute for Surgical Research, Germany Subjects: 12 male Sprague-Dawley rats Interventions: 6 rats acted as controls, and 6 had brain death induced by i nflation of an intracranial balloon. Main outcome measures: Mean arterial pressure, serum concentration of antid iuretic hormone (ADH), thyroxine (T-4), free-T-4, triiodothyronine (T-3) an d free-T-3, bile production, intravital fluorescence microscopy and electro n microscopic appearances. Results: After induction of brain death mean arterial pressure rose within 5 minutes followed by significant hypotension (p < 0.01). ADH concentration was reduced (p < 0.01), as was bile production (p<0.05). There was impaire d sinusoidal perfusion and increased interaction between leucocytes and end othelium in the hepatic microvasculature. The electron microscopic analysis showed vacuolisation of hepatocytes. Conclusion: macrohaemodynamics, ADH homeostasis, and the hepatic microcircu lation deteriorate after brain death, which leads to histomorphological dam age of hepatocytes and compromised liver function.