[Evaluation of arterial pressure in the first 3 days of life in a group of healthy newborn infants weighing between 2000 and 4600 g at birth]. / Valutazione della pressione arteriosa nei primi tre giorni di vita in un gruppo di neonati sani con peso alla nascita da 2000 a 4600 g.

Systolic, mean and diastolic arterial pressure (AP) was measured on the first and third days of life in a group of 270 infants born in our Hospital. The aim of this work is to see if there are modifications of AP in the first 3 days of life, and correlations between AP and weight at birth, gestational age, and different methods of delivery. Gestational age was between 34 and 42 weeks and birth weight between 2000 and 4600 grams. We excluded infants who developed any illness, those with a low Apgar score, and those whose mothers were given antihypertensive drugs. None of the examined infants received transfusion or drug which could affect the AP. Blood pressure was measured using the automatic oscillometric method. The infant's group was divided into 6 subgroups according to weight (table 1). For statistical analysis we used linear regressions and Student's "t" test. According to our data no correlation was found between birth weight and AP, nor between AP and gestational age; results obtained from other studies concerning this subject didn't agree. On the other and, we found an increase of values of AP in the third day; this agrees with the results of other Authors and is considered a consequence of the rise in peripheral vascular resistance in the postanal period. No difference was observed between the AP values of infants born by normal delivery and cesarean section.