Study of the Normal Value of Neonatal Blood Pressure according to Postconceptional Age / 대한주산의학회잡지

ABSTRACT

OBJECTIVE: Neonatal blood pressure is one of the vital signs used to assess the general health of a newborn infant. But, it is difficult to measure and varies according to the model of sphygmomanometer, the used method, the postconceptional age, birth weight, asphyxia, postnatal age and activity. We have assessed the rnean value of blood pressure(BP) according to postconceptional age. Variations caused by the postconceptional age, birth weight, body surface area(BSA), postnatal age, and sex were analyzed to determine the rnost important factor influencing the neonatal BP. METHODS: This study included 448 normal fullterm infants and healthy preterm infants born from Jan. 1995 to Aug. 1997 at Ewha Dongdaemoon and Mokdong Hospital. The BP was taken on day 1, 3, 5 with the oscillometric device(Dinamap 1846 critikon Inc.), for premature infants BP was followed up every week afterward. RESULTS: The neonatal BP was related to the postconceptional age(R=0.204, P<0.05), BSA(R =0.191, P<0.05), birth weight(R=0.183, P<0.05) and the postnatal age in fullterm infants(R=0.022, P<0.05) but not with the sex of the infant. The postconceptional age was the most significant variable among those influencing the BP. The normal value of the systolic and the diastolic BP was expressed as mean+/-2SD according to the postconceptional age, less than 28 weeks(n=27) systolic/diastolic pressure 50.4+/-23.1mmHg/26.2+/-12.8mmHg, 28-32weeks(n= 63) 60.1+/- 30.6mmHg/33.6+/-16.7mmHg, 32-36weeks(n = 139) 63.2+/- 20.4mmHg/37.7+/- 19.8 mmHg, 36- 40weeks(n=543) 65.6+/-18.5mmHg/38.6+/-17.3mmHg, more than 40weeks(n= 136) 67.7+/-16,9mmHg/39.3+/- 15.8mmHg. The increase in blood prssure with the postconceptional age was statistically significant. CONCLUSION: The normal range of neonatal BP, especially preterm infants, was presented, and it would be much valuable for the evaluation of BP in neonate if standardized by postconceptional age.