Prophylactic Phenylephrine Infusion Versus Treatment With Vasopressor Bolus as Needed During Nonurgent Cesarean Delivery and Neonatal Acidemia: A Retrospective Cohort Study (2016-2021)

( Int J Obstet Anesth . 2024;60:104253. DOI: 10.1016/j.ijoa.2024.104253) Spinal anesthesia is commonly used for nonurgent cesarean deliveries (CD) with spinal hypotension—typically defined as a systolic blood pressure (SBP) below 100 mm Hg or <80% of baseline value—occurring in up to 74% of these procedures. The reported incidence of neonatal acidemia varies widely, ranging from 0.76% to 27%, and is often linked to maternal spinal hypotension. Historically, efforts to prevent spinal hypotension have included the use of vasopressors, either in bolus doses or as continuous infusions. In 2018, prophylactic phenylephrine infusions were introduced, which aim to stabilize maternal blood pressure during CD. This study investigated how prophylactic phenylephrine infusions affects neonatal acidemia, compared with the traditional approach of administering vasopressors only as needed.