You are caring for a parturient at 38 weeks gestation who is undergoing an urgent cesarean delivery with spinal anesthesia due to labor with a breech presentation and fetal macrosomia. Her medical history includes pulmonary hypertension, for which she is currently taking sildenafil three times daily. The obstetricians are having a difficult time delivering the large fetus and ask you to administer sublingual nitroglycerin, which you refuse. Your refusal is due to concern about which of the following adverse effects?
Sildenafil is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5, and administration results in smooth muscle relaxation. Besides its use in erectile dysfunction, sildenafil is approved by the U.S. Food and Drug Administration for the treatment of pulmonary arterial hypertension. Nitroglycerin causes smooth muscle relaxation by releasing nitric oxide. Nitroglycerin is among those agents that can be used to induce rapid uterine relaxation, and its use for...
