Mean arterial blood pressure changes in premature infants and those at risk for intraventricular hemorrhage

Bedside microcomputer-derived, minute-to-minute mean arterial pressure (MAP) values during the first 48 hours of life were studied in 100 preterm babies with birth weight ≤1500 gm. In those babies (n=72) with no periventricular-intraventricular hemorrhage (PV-IVH) or with grade 1 PV-IVH, the MAP values increased during the study period, with minute-to-minute variation and interval undulation. The MAP values in those with birth weight>1000 gm were higher than in those of lower birth weight. Infants in whom grades 2 to 4 PV-IVH developed (n=28) had consistently lower MAP values during the study period. Minute-to-minute variability, expressed as the average of the coefficients of variation at 15-minute intervals, did not differ between birth weight groups, nor did they differ between the PV-IVH group and their matched control subjects. However, those with PV-IVH spent a greater percentage of time, with a coefficient of variation≥13% or