Distinct outcomes of labetalol exposed infants: case reports and systematic review

Abstract

Background: The adverse effects of long-term maternal exposure of labetalol on neonates have been recognized clinically. But there are few systematic studies on their clinical demonstrations and potential mechanisms. Methods: A death case of an infant with long-term maternal labetalol exposure was reported and compared with two case reports from the literature. A systematic literature review was carried out followed by a retrospective analysis on neonatal labetalol withdrawal effects. Results: It was discovered that labetalol withdrawal effects initially cause various degrees of hypotension, hypoglycemia, and bradycardia among exposed neonates. Some life-threatening cases can also occur within 1 week after birth. Long-term maternal exposure of labetalol, preterm infants with birth asphyxia, acidosis, hypoalbuminemia, and cardiac defects are their primary features. Possible mechanisms were concluded as labetalol-induced effects on the vascular and sympathetic nervous system as well as tissue oxygen extraction. Conclusions: Neonatal labetalol withdrawal effects include early-onset and late-onset demonstrations, the latter can be life-threatening. A possible mechanism is multiple factors induced imbalance of sympathetic homeostasis increases neonatal vulnerability to common stresses. Long-term exposed preterm infants complicated with asphyxia, acidosis, hypoalbuminemia and cardiac defects, should be provided with intense care during the first week after birth. Further work is necessary to enrich this hypothesis.