Vasopressor Strategy for Neuraxial Related Hypotension During CrashCesarean
Keywords:
Cesarean section, Spinal anesthesia, Hypotension, Vasoconstrictor agents, Phenylephrine, NorepinephrineAbstract
Background: Crash cesarean requires rapid, reliable hemodynamic control. Neuraxial anesthesia
frequently precipitates hypotension, therefore optimized vasopressor strategies are central to maternal safety and fetal perfusion.
Methods: We conducted a systematic search of PubMed from inception to April 2024. Eligible studies were clinical trials or cohorts evaluating vasopressors for prevention or treatment of neuraxial related hypotension during crash or urgent cesarean. Two reviewers screened records, assessed risk of bias with appropriate tools, and extracted data in duplicate. The primary outcome was the incidence of maternal hypotension. Secondary outcomes were maternal bradycardia, nausea or vomiting, rescue vasopressor use, and neonatal Apgar scores and umbilical arterial pH. No meta-analysis was performed.
Results: The search identified 547 records, 72 duplicates were removed, 475 titles and abstracts were screened, 45 full texts were assessed, and 10 studies were included (total n = 1150). Prophylactic infusions reduced hypotension compared with reactive bolus strategies, with absolute risk differences commonly between 30 and 70 percentage points across trials, for example 20% vs 90%, 31–37% vs 67%, and 15.5% vs 71.1. When active agents were compared, norepinephrine and phenylephrine maintained blood pressure similarly, while norepinephrine reduced maternal bradycardia relative to phenylephrine. Ephedrine was associated with more maternal nausea or vomiting, for example 22.2% vs 4.4% with phenylephrine. Neonatal outcomes, including umbilical arterial pH and Apgar scores, did not differ meaningfully across agents.
Conclusions: In crash or urgent cesarean under neuraxial anesthesia, protocolized vasopressor infusions provided superior prevention of hypotension compared with bolus only approaches. Agent selection may be individualized, with phenylephrine or norepinephrine as first line and ephedrine reserved for selected physiologic profiles.
