Transient suppression of pancreatic endocrine function in patients following brain death

To investigate pancreatic endocrine function in brain-dead patients, an intravenous glucose tolerance test (i.v. GTT) was performed in 8 brain-dead subjects maintained using the combined administration of vasopressin (ADH) and catecholamines during the first 3 days following the onset of brain death. Ten healthy adults served as control subjects. Although plasma glucose concentrations markedly increased and exceeded 300 mg/dl in most subjects just after the onset of brain death, they decreased to less than 200 mg/dl in most subjects after 24 h. The early insulin release also was significantly lower in brain dead subjects compared to controls (p < 0.01). The late insulin release was not decreased compared to controls but rather increased, which was accompanied by decreased glucose disappearance rate. The early insulin release recovered rapidly during the first 3 days following brain death without significant changes in the plasma hormone concentrations such as epinephrine, human growth hormone, thyroid-stimulating hormone, triiodothyronine, thyroxine, cortisol, and glucagon. The early insulin release and the plasma glucose concentration just before i.v. GTT was negatively correlated (R = -0.55, p < 0.05). We suggest awaiting recovery from hyperglycemia and early insulin release provides a reasonable approach to transplantation of the pancreas.