A Dose-Response Study of Four Fixed Weight-Based Phenylephrine Dosages in Obese Cesarean Delivery Patients to Prevent Spinal Anesthesia-Induced Hypotension

• Published in: Clinical pharmacokinetics 2024-12, Vol.63 (12), p.1749
• Main Authors: Xing, Li, Xu, Hai-Feng, Wang, Yang, Shi, Hong-Shu, Xiao, Fei, Shen, Yao-Hua, Lin, Su-Feng
• Format: Article
• Language: English
• Subjects: Adult; Anesthesia, Epidural - adverse effects; Anesthesia, Epidural - methods; Anesthesia, Obstetrical - adverse effects; Anesthesia, Obstetrical - methods; Anesthesia, Spinal - adverse effects; Anesthesia, Spinal - methods; Blood Pressure - drug effects; Body Weight; Cesarean Section - methods; Dose-Response Relationship, Drug; Female; Humans; Hypotension - chemically induced; Hypotension - prevention & control; Obesity - complications; Phenylephrine - administration & dosage; Pregnancy; Vasoconstrictor Agents - administration & dosage; Vasoconstrictor Agents - therapeutic use
• ISSN: 1179-1926; 1179-1926
• DOI: 10.1007/s40262-024-01448-2

Reports have suggested the use of intravenous infusion of vasopressors as an approach to prevent spinal anesthesia-induced hypotension (SAIH) in women undergoing cesarean deliveries. However, data on the suitability of this technique for obese people are limited. As such, the current experiment was designed to clarify the dose-response relationship associated with the preventive administration of phenylephrine to avoid SAIH during cesarean delivery in obese parturients under combined spinal-epidural anesthesia. The current study included 100 parturients with a body mass index ≥30 kg/m who were undergoing cesarean section delivery. They were randomly treated with phenylephrine at different doses: 0.375, 0.5, 0.625, or 0.75 μg/kg/min. An infusion of phenylephrine was deemed beneficial if hypotension was absent, with hypotension defined as a systolic blood pressure