Hypoplastic Left Heart Syndrome Surgical Treatment Augmented with Phenoxybenzamine

Before these new procedure became available, comfort care was the only option for these neonates. When neonates with HLHS undergo the three-step Norwood procedure, they are expected to live to adulthood with a single ventricle supplying all the blood needed for the pulmonary and systemic circulations. They also end up depending on a shunt to supply blood between the pulmonary arteries and the aorta. Though these procedures are remarkable, they still have a high mortality rate because the cardiac output is decreased. There is also an imbalance between the pulmonary and systemic circulation which can result in a sudden collapse of the heart [1]. Because of the high mortality rate, many surgeons are opting for treatment with vasodilators, like phenoxybenzamine, postoperatively. The goal of treatment with phenoxybenzamine is to balance the circulation by reducing systemic vascular resistances (SVR) so that the neonates can have higher systemic blood flow as opposed to pulmonary blood flow. Ever since phenoxybenzamine has been tried postoperatively, however, there has been no significant research that reports on its effectiveness. This article discusses the basic pharmacology of phenoxybenzamine, and physiological and surgical results of its use with the Norwood procedure [1]. Discussion