Normative blood pressure data in non-ventilated premature neonates from 28-36 weeks gestation.

Blood pressure (BP) measurement in the premature neonate is an essential component of neonatal intensive care. Despite significant advances in neonatal care, the data available on BP in the premature neonate are limited. The aim of this study was to determine normative BP measurements for non-ventilated stable premature neonates of gestation age 28-36 weeks in the first month of life using an oscillometric method. Neonates born at 28-36 weeks gestation who did not require ventilation for >24 h or inotrope support for >24 h were enrolled into the study. Blood pressure measurements were taken on days 1, 2, 3, 4, 7, 14, 21 and 28 where possible prior to discharge. A total of 147 infants were included in the study, and 10th and 90th percentiles BPs were obtained for gestation as well as birthweight. Changes in BP over time for each gestational week were determined. A significant difference in BP from day 1 to day 7 and from day 7 to 14 was observed in those born at less than 31 weeks gestation, and from day 1 to 7 in those born at more than 31 weeks gestation, but not from day 14 to 21 and from day 21 to 28 for any gestation period. Data on BP for stable non-ventilated premature infants using an oscillometric method provide useful information for determining hypotension and hypertension in the premature neonate. Premature neonates stabilize their BP after 14 days of life, and at this time they have a BP similar to that of term infants.