Association of low systolic and diastolic blood pressure with significant patent ductus arteriosus in the very low birth weight infant.

The systolic, diastolic, and pulse pressures of 34 infants weighing less than 1200 g, who required mechanical ventilation for hyaline membrane disease, were prospectively evaluated in the first week of life and related to the magnitude of ductal shunting. Seventeen infants developed a large patent ductus arteriosus (PDA) corresponding to significant left-to-right ductal shunting and requiring surgical ligation. By the second day of life these patients with large PDAs had significantly lower mean systolic and diastolic BPs than the non-PDA infants. There were no significant differences in pulse pressures between groups. Both systolic and diastolic BPs promptly returned to control values after ligation. A mean diastolic BP less than 28 mm Hg on the third day of life was significantly associated with a PDA in 93% of patients.