Mechanism: extensive vasodilation triggered by nitrous oxide (NO) and cyclic guanosine monophosphate (cGMP).
Features of the vasoplegic syndrome:
(1) severe hypotension
(2) tachycardia
(3) cardiac output that is normal or increased
(4) low systemic vascular resistance
(5) decreased cardiac filling pressures
(6) exclusion of sepsis and alternative explanations
The vasoplegic syndrome can occur:
(1) following open heart surgery with cardiopulmonary bypass
(2) off-pump coronary artery bypass surgery
(3) liver transplantation
Risk factors for vasoplegia include:
(1) pre-operative therapy with angiotensin-converting enzyme (ACE) inhibitors
(2) pre-operative administration of intravenous heparin
(3) blood product transfusion
