Comparison of terbutaline and atosiban as tocolytic agents in intrauterine repair of myelomeningocele: a retrospective cohort study

Background: Myelomeningocele (MMC) is a neural tube defect disease. Antenatal repair of fetal MMC is an alternative to postnatal repair. Many agents can be used as tocolytics during the in utero fetal repair such as β2-agonists and oxytocin receptor antagonists, with possible maternal and fetal repercussions. This study aims to compare maternal arterial blood gas analysis between terbutaline or atosiban, as tocolytic agents, during intrauterine MMC repair. Methods: Retrospective cohort study. Patients were divided into two groups depending on the main tocolytic agent used during intrauterine MMC repair: atosiban (16) or terbutaline (9). Maternal arterial blood gas samples were analyzed on three moments: post induction (baseline, before the start of tocolysis), before extubation, and two hours after the end of the surgery. Results: Twenty-five patients were included and assessed. Before extubation, the terbutaline group showed lower arterial pH (7.347 ± 0.05 vs. 7.396 ± 0.02 for atosiban, p = 0.006) and higher arterial lactate (28.33 ± 12.76 mg.dL−1 vs. 13.06 ± 6.35 mg.dL−1, for atosiban, p = 0.001) levels. Conclusions: Patients who received terbutaline had more acidosis and higher levels of lactate, compared to those who received atosiban, during intrauterine fetal MMC repair.