[Cerebral hemorrhage and periventricular leucomalacia in preterm neonates after intravenous tocolysis with fenoterol: results of postnatal ultrasound examination]

Abstract

Background: This study tested whether tocolysis with beta-adrenergic agonists (Fenoterol) had an effect on the frequency of cerebral lesions in preterm neonates.

Patients and methods: Head ultrasound scans of preterm neonates who were born after long-term (> 24 h) tocolysis were compared with scans of preterm neonates without preceding tocolysis. The gestational and neonatal data were analyzed retrospectively.

Results: Preterm neonates after (n = 102) and without (n = 101) tocolysis were subdivided into three groups according to their gestational age (23 - 28 wk: n = 41; 29 - 33 wk: n = 66; 34 - 36 wk: n = 96). Within these groups, no significant differences were found with respect to birth weight, rate of cesarean section, or pulmonary morbidity. Preterm babies < 28 weeks of gestation from the control group had lower Apgar scores (after 1 and 5 minutes, respectively) and arterial umbilical cord pH values. Intravenous tocolysis did not lead to an increase in pseudocystic periventricular leucomalacia (PVL) or intracerebral hemorrhage (ICH) in any of the subgroups studies. However, cerebral lesions were found in preterm neonates after tocolysis who exhibited signs of infection (29 - 33 wk: PVL n = 2; 23 - 28 wk: ICH n = 1) and in preterm neonates without tocolysis who had undergone fetal hypoxia or abruptio placentae (29 - 33 wk: PVL n = 4; antenatal terminal vein bleeding n = 1; 23 - 28 wk: PVL n = 2; terminal vein bleeding n = 5; posterior cerebral artery bleeding n = 1). When compared to preterm neonates of 34 - 36 weeks of gestation, the risk of infection was increased 4-fold in neonates of 29 - 33 weeks of gestation (odds ratio 5.43, 1.10 - 26.83) and 10-fold in neonates of 23 - 28 weeks of gestation (odds ratio 20.50, 3.65 - 115.03). Chorioamnionitis also was a more common finding in preterm neonates < 28 weeks of gestation.

Conclusion: Preterm neonates who were born after intravenous long-term (> 24 h) tocolysis with Fenoterol do not exhibit an increase in periventricular leucomalacia or intracranial hemorrhage. The occurrence of cerebral lesions in these patients merely depends on their degree of immaturity and on the presence or absence of perinatal infection. In preterm neonates without tocolysis, brain lesions are mainly associated with hypoxic events.