The hemodynamic effects of neonatal patent ductus arteriosus shunting on superior mesenteric artery blood flow

Abstract

Objective: To determine if the ratio of the pulsatility index (PI) of the left pulmonary artery to the PI of the descending aorta, the Rp/Rs index, correlates with the degree of ductal steal from the intestine in neonates with a patent ductus arteriosus (PDA). Study design: Echocardiograms and Doppler studies of the superior mesentric artery (SMA) were performed in 41 neonates less than 35 weeks gestational age with a hemodynamically significant PDA (hsPDA). Results: There was a significant negative correlation between the Rp/Rs index and the SMA PI after controlling for ductal size (r = -0.476, p < 0.008). Conclusions: The Rp/Rs index can be used as an indicator of ductal steal on intestinal blood flow. The Rp/Rs index may be a useful adjunct to existing and new techniques for improving early assessment and treatment of hsPDA, and for evaluating the effects of hsPDA on systemic organs. © 2005 Nature Publishing Group All rights reserved.