Blood pressure in full-term healthy neonates

The blood pressure (BP) of 46 healthy full-term infants was studied in the first 6 consecutive days of life using the Dinamap. The BP gradually increased with age to peak at 4 or 5 days of age before subsiding a little at 6 days. There was a significant increase in BP values from the second to the third day of life in both the systolic and diastolic pressures during the waking state but not during sleep. The waking and sleeping BP, almost identical in the first day, diverged with increasing age, although no significant difference could be demonstrated between the respective values during the 6 days of study in systolic, diastolic, or mean arterial pressure. BP values obtained in the left and right upper limbs and right lower limb were similar for the respective days, with minor variations in pattern. The waking and sleeping heart rate, identical on the first day, also diverged with increase in age but again no significant difference was observed on the first 6 days. There was no correlation between the BP and heart rate on any of the 6 days. However, a positive correlation between the daily mean systolic pressure and heart rate only in the waking state was observed over the course of the 6-day study period.