Use of Targeted Neonatal Echocardiography to Prevent Postoperative Cardiorespiratory Instability after Patent Ductus Arteriosus Ligation

Abstract

To investigate the value of targeted neonatal echocardiography (TnECHO) in predicting cardiorespiratory instability after patent ductus arteriosus (PDA) ligation, and to evaluate the impact of TnECHO-directed care. We reviewed serial echocardiography evaluations of 62 preterm infants after PDA ligation to investigate the relationship between indices of myocardial performance and postoperative cardiorespiratory instability. Apredictive model was developed based on TnECHO criteria, with targeted initiation of intravenous milrinone. A comparative evaluation was performed between matched infants in the previous era (epoch 1; n=25) and current era (epoch 2; n=27) of TnECHO-guided treatment. Left ventricular output <200 mL/kg/min at 1 hour after PDA ligation was a sensitive predictor of systemic hypotension and the need for inotropes, and was used for initiation of i.v. milrinone infusion in epoch 2. Infants treated with milrinone had a lower incidence of ventilation failure (15% vs 48%; P=.02) and less need for inotropes (19% vs 56%; P=.01), and showed a trend toward improved oxygenation (P=.08). TnECHO facilitates early detection of infants at greatest risk for subsequent cardiorespiratory deterioration. Administration of milrinone to neonates with low cardiac output may lead to improved postoperative stability.