Prophylaxis and Management of Vasoplegic Syndrome

The concept of the vasoplegic syndrome, characterized by hypotension associated with profound vasodilation unresponsive to conventional catecholamines or vasopressors, was introduced in association with CPB in the late 1990s by Gomes et al.cardiac vasoplegia syndrome is a form of vasodilatory shock that occurs in 9% to 44% of patients after cardiopulmonary bypass (CPB) surgery. These patients have profound vasodilation and loss of systemic vascular resistance, resulting in severe hypotension despite high cardiac outputs and adequate fluid resuscitation. This leads to inadequate tissue perfusion and metabolic acidosis.Cardiac vasoplegia syndrome has become a well recognized complication of cardiac surgery requiring CPB and is characterized by significant hypotension, high or normal cardiac outputs, low systemic vascular resistance and an increased requirement for vasopressors. This syndrome reflects the complex interactions among plasma proteins, leukocytes, platelets and endothelial cells.Vasoplegia syndrome carries a poor prognosis, especially norepinephrine- resistant vasoplegia. Catecholamine resistant vasoplegia lasting for more than 36 to 48 hours has a mortality rate as high as 25%.36 Vasoplegia syndrome is also associated with longer hospital stays, prolonged ICU stays, prolonged mechanical ventilation and more sternal infections.The initial management of patients with vasoplegia requires vasopressors, which do restore the hemodynamic function in most but not all patients; the most frequently used vasopressors are norepinephrine, VP and phenylephrine.Methylene blue provides an alternative drug for the treatment of catecholamine refractory vasoplegia.