Early cardiovascular effects of glucocorticoids for premature infants withbronchopulmonary dysplasia.

Objectives. - The aim of this study was to analyze the time course of cardi ovascular effects in glucocorticoid-treated premature infants with bronchop ulmonary dysplasia (BPD), Methods. - In a retrospective case study, 63 ventilator-dependent very-low- birth-weight neonates (mean gestational age = 27.9 +/- 2 weeks and mean bir th weight = 920 +/- 275 g) treated with dexamethasone (52%) or betamethason e (48%) were studied. The average value for each study day was calculated f or systolic arterial blood pressure and heart rate. Results. - At initiation of treatment, blood pressures increased significan tly from pre-treatment to day 1 and continued to increase during the first week: as a percentage of pre-treatment baseline the mean increase for systo lic arterial blood pressure was 19% (95% confidence interval [Cl] = 16, 22) on day 2 (P < 0.001). The maximum amplitude of variation was observed befo re day 2 for 75% of the study group. As a group as a whole, the heart rate value significantly decreased on day 1 (mean difference = -14.6 beats/min; 95% Cl = -16.5, -12.6; P < 0.001), and then reached pre-treatment value wit hin one week. Cardiovascular response was independent of gestational age, b irth weight and postnatal age at the beginning of treatment. Conclusion. - During postnatal steroid therapy a rise in blood pressure is a common side effect, but bradycardia is mentioned very occasionally. The p resent study shows a marked increase in blood pressure during the first 48 hours concomitant with a decrease in heart rate. The inverse relationship b etween systolic arterial blood pressure and heart rate suggests a barorefle x response. (C) 2001 Editions scientifiques et medicales Elsevier SAS.