Circulatory disturbances during the first postnatal 24 hours in extremely premature infants 25 weeks or less of gestation with histological fetal inflammation

Abstract

To investigate the effect of pre-existing fetal inflammation on hemodynamics during the first postnatal 24 h in extremely premature infants <or= 25 weeks of gestation. We defined fetal inflammation as the infiltration of neutrophils into the chorionic plate vessels or umbilical cord vessels on histological examination. In 41 infants born between 22 and 25 weeks of gestation, 23 displayed fetal inflammation and 18 displayed no fetal inflammation. Circulatory indices including blood pressure, heart rate, average urine flow, catecholamine index, ejection fraction of the left ventricle, and volume load for 24 h were compared between the two groups, as well as the incidence of intraventricular hemorrhage (IVH), periventricular leukomalacia (PVL), and death. The comparisons were made with repeated measure anova and with Fisher's exact test, or unpaired t-test. Probability values <0.05 were considered significant. Infants with and without fetal inflammation had similar birthweights and gestational age. There was no significant difference in incidence of PVL and death. However, infants with fetal inflammation had a significantly higher incidence of IVH >or= 3 than infants with no fetal inflammation (49% vs 17%) (P=0.04). Infants with fetal inflammation had significantly higher heart rate (P=0.005), catecholamine index (P=0.019) and volume load (P=0.021). Histological evidence of fetal inflammation in extremely premature infants is associated with circulatory disturbances over the first 24 h of life and increases in the incidence of IVH >or= 3.