The pulse pressure in a premature infant less than 37 weeks gestational age with a patent ductus arteriosus

Abstract

A widened pulse pressure could be a sign of a patent ductus arteriosus in an infant. This is defined as a difference between systolic and diastolic blood pressure of greater than 15 to 25 mmHg, in premature infants and greater than 25 mmHg in term infants [1]. It is thought that diastolic runoff from blood flow shunting across the aorta to the pulmonary artery, through the patent ductus arteriosus, will produce a lower diastolic pressure and therefore widen the pulse pressure in the affected infant [1]. In our retrospective chart review, 116 premature infants were identified with a patent ductus arteriosus and compared to 42 premature infants without a patent ductus arteriosus. The blood pressures obtained were recorded for the first 7 days of life of the patients. Our studies revealed that premature infants with a patent ductus arteriosus had a mean pulse pressure of19 mmHg (p-value 0.129) when compared to infants without a patent ductus arteriosus,16 mmHg, on day 1 of life. The mean pulse pressures were ~20 mmHg in both groups on days 2 - 3. On days 4 - 7 mean pulse pressures were greater than20 mmHg for both groups (p-values 0.35, 0.19, 0.74, 0.8). It was noticed that mean pulse pressures in the patent ductus arteriosus group were within 0-4 mmHg when compared to the group without a patent ductus arteriosus and therefore not clinically relevant or statistically significant.