Bolus norepinephrine and phenylephrine for maternal hypotension during elective cesarean section with spinal anesthesia: a randomized, double-blinded study
10.1097/CM9.0000000000000621
- VernacularTitle:Bolus norepinephrine and phenylephrine for maternal hypotension during elective cesarean section with spinal anesthesia: a randomized, double-blinded study
- Author:
Xian WANG
1
;
Mao MAO
;
Su-Su ZHANG
;
Zhao-Hui WANG
;
Shi-Qin XU
;
Xiao-Feng SHEN
Author Information
1. Department of Anesthesiology, Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, Jiangsu 210004, China
- Keywords:
Norepinephrine;
Phenylephrine;
Cardiac output;
Cesarean section
- From:
Chinese Medical Journal
2020;133(5):509-516
- CountryChina
- Language:Chinese
-
Abstract:
Background::In recent years, norepinephrine has attracted increasing attention for the management of maternal hypotension during elective cesarean section with spinal anesthesia. Intermittent bolus is a widely used administration paradigm for vasopressors in obstetric anesthesia in China. Thus, in this randomized, double-blinded study, we compared the efficacy and safety of equivalent bolus norepinephrine and phenylephrine for rescuing maternal post-spinal hypotension.Methods::In a tertiary women’s hospital in Nanjing, China, 102 women were allocated with computer derived randomized number to receive prophylactic 8 μg norepinephrine (group N; n = 52) or 100 μg phenylephrine (group P; n = 50) immediately post-spinal anesthesia, followed by an extra bolus of the same dosage until delivery whenever maternal systolic blood pressure became lower than 80% of the baseline. Our primary outcome was standardized maternal cardiac output (CO) reading from spinal anesthesia until delivery analyzed by a two-step method. Other hemodynamic parameters related to vasopressor efficacy and safety were considered as secondary outcomes. Maternal side effects and neonatal outcomes were collected as well. Results::Compared to group P, women in group N had a higher CO (standardized CO 5.8 ± 0.9 vs. 5.3 ± 1.0 L/min, t = 2.37, P = 0.02) and stroke volume (SV, standardized SV 73.6 ± 17.2 vs. 60.0 ± 13.3 mL, t = 4.52, P < 0.001), and a lower total peripheral resistance (875 ± 174 vs. 996 ± 182 dyne·s/cm 5, t = 3.44, P < 0.001). Furthermore, the incidence of bradycardia was lower in group N than in group P (2% vs. 14%, P= 0.023), along with an overall higher standardized heart rate (78.8 ± 11.6 vs. 75.0 ± 7.3 beats/min, P = 0.049). Other hemodynamics, as well as maternal side effects and neonatal outcomes, were similar in two groups ( P > 0.05). Conclusions::Compared to equivalent phenylephrine, intermittent bolus norepinephrine provides a greater CO for management of maternal hypotension during elective cesarean section with spinal anesthesia; however, no obvious maternal or neonatal clinical advantages were observed for norepinephrine.
