BLOOD-PRESSURE INCREASES IN RESPONSE TO FEEDING IN THE TERM NEONATE

We studied blood pressure and heart rate of 18 medically well newborn babies before, during, and after feeding. Seven were breast-fed and 11 bottle-fed and all were studied between 24 and 92 hr of age. There was an increase in heart rate associated with sucking on a pacifier but no additional increase with feeding. By 30-60 min after feeding, heart rate had returned to baseline value. Blood pressure. however, did increase in response to feeding and showed a greater increase in the breast-fed group than in the bottle-fed group. Systolic blood pressure rose from 72 mmHg in the basal state to 85 mmHg during the first 3 min of feeding in the bottle-fed babies and from 73 to 99 mmHg during comparable periods in the breast-fed babies. The results for diastolic blood pressure were similar except that changes within the bottle-fed group were not statistically significant. Bottle-fed babies rose only from 42 to 47 mmHg while breast-fed babies rose from 42- to 61 mmHg from basal conditions to feeding. Blood pressure responses to feeding may have implications for susceptibility to necrotizing enterocolitis, for future blood pressure liability in adulthood and for later hypertensive disease.