Hemodynamic effects of delayed cord clamping in premature infants.

BACKGROUND AND OBJECTIVE Delayed cord clamping (DCC) has been advocated during preterm delivery to improve hemodynamic stability during the early neonatal period. The hemodynamic effects of DCC in premature infants after birth have not been previously examined. Our objective was to compare the hemodynamic differences between premature infants randomized to either DCC or immediate cord clamping (ICC). METHODS This prospective study was conducted on a subset of infants who were enrolled in a randomized controlled trial to evaluate the effects of DCC versus ICC. Entry criteria included gestational ages of 24(0) to 31(6) weeks. Twins and infants of mothers with substance abuse were excluded. Serial Doppler studies were performed at 6 ± 2, 24 ± 4, 48 ± 6, and 108 ± 12 hours of life. Measurements included superior vena cava blood flow, right ventricle output, middle cerebral artery blood flow velocity (BFV), superior mesenteric artery BFV, left ventricle shortening fraction, and presence of a persistent ductus arteriosus. RESULTS Twenty-five infants were enrolled in the DCC group and 26 in the ICC group. Gestational age, birth weight, and male gender were similar. Admission laboratory and clinical events were also similar. DCC resulted in significantly higher superior vena cava blood flow over the study period, as well as greater right ventricle output and right ventricular stroke volumes at 48 hours. No differences were noted in middle cerebral artery BFV, mean superior mesenteric artery BFV, shortening fraction, or the incidence of a persistent ductus arteriosus. CONCLUSIONS DCC in premature infants is associated with potentially beneficial hemodynamic changes over the first days of life.