Initial enthusiasm for the use of vasodilators to improve pulmonary hemodynamics and symptomatic status in pulmonary hypertension of diverse etiologies has been tempered by the high incidence of serious complications, especially hypotension. However, the unrelenting hypoxia of pulmonary hypertension without treatment and the improved pulmonary hemodynamics and symptomatic states of some patients during vasodilator therapy provide the rationale for a therapeutic test of vasodilators in hemodynamically monitored patients. We report that vasodilator therapy in a patient with severe hypoxia due to pulmonary hypertension and sickle cell crisis was fatally complicated by hypotension and extensive small-bowel infarction.