Unexplained and prolonged perioperative hypotension after orthotopic liver transplantation: undiagnosed systemic mastocytosis.

Arterial vasodilation is common in end-stage liver disease, and systemic hypotension often may develop, despite an increase in cardiac output. During the preparation for and the performance of orthotopic liver transplantation, expected and transient hypotension may be caused by induction agents, anesthetic agents, liver mobilization, or venous clamping. A mild decrease of the already low systemic vascular resistance is often observed, and intermittent use of short-acting agents for vasopressor support is not uncommon. In this report, we describe a patient with unexpected and prolonged hypotension due to vasodilation during and after orthotopic liver transplantation. The preoperative end-stage liver disease evaluation, intraoperative events, and intensive care unit course were reviewed, and no cause for the vasodilation and prolonged hypotension was evident. The explant pathology report was later available and showed systemic mastocytosis. We hypothesize that the unexpected hypotension and vasodilation were caused by mast cell degranulation and its systemic effects on arterial tone.