Combined usage of inhaled and intravenous milrinone in pulmonary hypertension after heart valve surgery

Secondary pulmonary hypertension is a frequent condition after heart valve surgery. It may significantly complicate the perioperative management and increase patients' morbidity and mortality. The treatment has not been yet completely defined principally because of lack of the selectivity of drugs for the pulmonary vasculature. The usage of inhaled milrinone could be the possible therapeutic option. Inodilator milrinone is commonly used intravenously for patients with pulmonary hypertension and ventricular dysfunction in cardiac surgery. The decrease in systemic vascular resistance frequently necessitates concomitant use of norepinephrine. Pulmonary vasodilators might be more effective and also devoid of potentially dangerous systemic side effects if applied by inhalation, thus acting predominantly on pulmonary circulation. There are only few reports of inhaled milrinone usage in adult post cardiac surgical patients. We reported 2 patients with severe pulmonary hypertension after valve surgery. Because of desperate clinical situation, we decided to use the combination of inhaled and intravenous milrinone. Inhaled milrinone was delivered by means of pneumatic medication nebulizer dissolved with saline in final concentration of 0.5 mg/ml. The nebulizer was attached to the inspiratory limb of the ventilator circuit, just before the Y-piece. We obtained satisfactory reduction in mean pulmonary artery pressure in both patients, and they were successfully extubated and discharged. Although it is a very small sample of patients, we conclude that the combination of inhaled and intravenous milrinone could be an effective treatment of secondary pulmonary hypertension in high-risk cardiac valve surgery patient. The exact indications for inhaled milrinone usage, optimal concentrations for this route, and the beginning and duration of treatment are yet to be determined.