Norepinephrine vs. Phenylephrine for Hypotension in Low-Dose Spinal Anesthesia for Cesarean Delivery

This clinical trial was conducted to compare the effectiveness and safety of two medications, norepinephrine and phenylephrine, in preventing hypotension during low-dose spinal anesthesia for cesarean delivery (CD). Although low-dose spinal anesthesia combined with opioids is widely used to mitigate hypotension, the incidence remains unacceptably high. Thus, vasopressors remain essential in maintaining maternal blood pressure during these procedures. In this study, 100 women were initially assessed, with 2 excluded. The remaining 98 were randomly assigned to receive a continuous infusion of either norepinephrine or phenylephrine. During the follow-up process, 2 patients from each group were lost, resulting in 47 participants per group for final analysis. The results showed that norepinephrine was significantly more effective, with a lower incidence of hypotension (14.9% vs. 42.6%). It also provided more stable heart rates with fewer episodes of bradycardia and less need for rescue medications. Both treatments were safe for the babies with comparable Apgar scores. This study suggests that Norepinephrine infusion at 0.05 mcg/kg/min is more effective than phenylephrine at 0.25 mcg/kg/min in preventing hypotension during low-dose SA in CD, providing better hemodynamic stability and fewer episodes of bradycardia

NCT Number	NCT07327320
Lead Sponsor	Tam Anh Research Institute
Conditions	Anesthesia, Spinal, Cesarean Section, Hypotension, Controlled
Enrollment	100 participants
Start Date	2024-06-06
Primary Completion	2025-10-04 (estimated)
Study Completion	2025-10-04 (estimated)
Updated on ClinicalTrials.gov	2026-01-21