Introduction: In cardiac surgery, patients with pulmonary hypertension (PHT) have markedly increased morbidity and mortality. The conventional therapy with intravenous vasodilators has limited results because of lack of pulmonary selectivity. We present our experience with inhaled iloprost, an analogue of prostacyclin, in significant secondary PHT (mean pulmonary artery pressure > 30 mmHg).
Method: Three adult patients, NYHA III, with moderate to severe PHT scheduled for elective valve replacement surgery maintained high values of pulmonary artery pressure after cardiopulmonary bypass (CPB). Iloprost was administered, after protamine, by an ultrasonic nebulizer at a concentration of 2 μg/mL. With an average nebulization rate 0.6 mL/min after 20 min a cumulative dose of 24 μg had been delivered. The following variables were measured or calculated: cardiac output and index (CO, CI); systolic and mean arterial blood pressures (SAP, MAP); systolic and mean pulmonary artery pressure (SPAP, MPAP); systemic and pulmonary vascular resistance (SVR, PVR).
Results: Patients were weaned from CPB on dobutamine and epinephrine to maintain a MAP greater or equal to 60mmHg. Haemodynamic data of the patients after protamine use and after inhaled iloprost are presented in Table 1.
Inhaled iloprost decreased MPAP by 30.8%, PVR by 26% and increased CI by 17%. Systemic arterial pressures were stable.
Conclusion: Inhaled iloprost appears to be a selective pulmonary vasodilator. The procedure is simple. Further studies are needed to promote routine use of inhaled iloprost in patients with perioperative moderate to severe secondary PHT in cardiac surgery.
1 Theodoraki K, Rellia P, Thanopoulos A, et al. Inhaled iloprost controls pulmonary hypertension after cardiopulmonary bypass. Can J Anaesth