Inhaled prostacyclin for the treatment of pulmonary hypertension after cardiac surgery

Objective: To describe the effects of inhaled prostacyclin administered after cardiopulmonary bypass (CPB) to a patient with severe pulmonary hypertension. Design: Case report and literature review. Setting: Cardiac surgical operating rooms and postoperative recovery unit. Patients: A 63-yr-old female who had undergone mitral and aortic valve replacement for rheumatic heart disease. Interventions: Administration of inhaled prostacyclin to decrease pulmonary artery pressures and to permit discontinuation of CPB. Measurements and Main Results: The patient was unable to be removed from CPB because of severe pulmonary hypertension precipitating acute right heart failure, despite administration of milrinone, norepinephrine, and nitroglycerin infusions. Inhaled prostacyclin was started at a dosage of 50 ng/kg/min, and the patient was able to be weaned from CPB. The inhaled prostacyclin was continued for 4 days postoperatively, with no signs of tolerance or systemic effects. Conclusion: Inhaled prostacyclin is an effective and selective pulmonary vasodilator at the dosage given in this report. Prolonged use is not associated with tolerance or systemic effects. The apparatus required for the delivery of inhaled prostacyclin is simple, inexpensive, and readily available in most hospitals. A review of the literature suggests that inhaled prostacyclin is effective in a number of clinical settings and displays comparable efficacy and hemodynamic effects to inhaled nitric oxide.