Use of milrinone in the management of haemodynamic instability following duct ligation.

Haemodynamic instability affects 22% to 29% of very low birth weight infants in the acute period following ligation of the ductus arteriosus and contributes to the mortality seen in this group. Since the sudden elevation of systemic vascular resistance has been recognised to be one of the factors contributing to this instability, milrinone, an afterload reducing agent, might potentially be of significant therapeutic benefit. This report presents the clinical course of an infant born at 26 weeks gestation who required surgical ligation of a haemodynamically significant patent ductus arteriosus after two unsuccessful 6-day courses of intravenous indomethacin. The post-operative period was characterized by oxygenation failure, rising blood pressure and echocardiographic signs indicative of diastolic dysfunction. The infant was successfully managed with milrinone, a phosphodiesterase inhibitor, which acts both as an "inodilator" and has lusitropy properties. Post-duct ligation haemodynamic instability in a preterm infant was successfully managed with milrinone. The role of afterload-reducing agents such as milrinone in this setting should, therefore, be systematically analyzed.