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Randomized Controlled Trial
. 2021 Apr;41(4):370-378.
doi: 10.1002/phar.2514. Epub 2021 Mar 5.

Prophylactic norepinephrine infusion for postspinal anesthesia hypotension in patients undergoing cesarean section: A randomized, controlled, dose-finding trial

Affiliations
Randomized Controlled Trial

Prophylactic norepinephrine infusion for postspinal anesthesia hypotension in patients undergoing cesarean section: A randomized, controlled, dose-finding trial

Yi Chen et al. Pharmacotherapy. 2021 Apr.

Abstract

Study objective: Prophylactic norepinephrine infusion effectively lowers the incidence of postspinal anesthesia hypotension. The optimal prophylactic dose of norepinephrine remains undefined. The purpose of this study was to investigate the optimal prophylactic dose of norepinephrine to prevent postspinal anesthesia hypotension in patients undergoing cesarean section.

Design: Prospective, double-blind, randomized, controlled, dose-finding trial.

Setting: Operating room from March 2020 to June 2020.

Patients: Ninety nine primipara or multipara women 18 - 40 years of age, singleton pregnancy ≥ 37 weeks, American Society of Anesthesiologists' physical status 1 or 2, scheduled for elective cesarean section under spinal anesthesia were included in this study.

Intervention: Patients were randomly assigned into groups to receive normal saline (NS) or one of four different prophylactic doses (0.025 [NE25], 0.05 [NE50], 0.075 [NE75], and 0.1 [NE100] ug/kg/min) of norepinephrine. The primary end point was the incidence of postspinal anesthesia hypotension (systolic blood pressure [SBP] < 80% of baseline) within 15 min after spinal anesthesia. Secondary outcomes included the overall stability of SBP control versus baseline (median performance error [MDPE] and median absolute performance error [MDAPE]), the dose that would be effective in preventing postspinal anesthesia hypotension in 50% (effective dose, ED 50) and 90% (ED90) of patients, other adverse events (bradycardia, nausea, vomiting, hypertension, and the total additional bolus of norepinephrine and atropine), and neonatal outcomes (blood gas values and Apgar scores).

Measurements and main results: The incidence of postspinal anesthesia hypotension in NS, NE25, NE50, NE75, and NE100 groups was 68.42% (13/19), 40.00% (8/20), 20.00% (4/20), 15.00% (3/20), and 10.00% (2/20), respectively. With increasing prophylactic doses of norepinephrine, the incidence of postspinal anesthesia hypotension decreased (p < 0.001), SBP was maintained closer to the baseline (MDPE, p < 0.001; MDAPE, p = 0.001), and the total additional bolus of norepinephrine decreased (p < 0.001). The ED50 and ED90 values of norepinephrine were 0.016 (95% CI: -0.014 - 0.033) and 0.088 (95% CI: 0.068 - 0.133) ug/kg/min, respectively. Other adverse effects, neonatal outcomes, and the total additional bolus of atropine did not differ among the five groups.

Conclusions: A prophylactic dose of 0.05 or 0.075 μg/kg/min norepinephrine prevents postspinal anesthesia hypotension in patients undergoing cesarean section.

Keywords: cesarean section; dose finding; hypotension; norepinephrine; spinal anesthesia.

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References

REFERENCES

    1. Allen TK, George RB, White WD, Muir HA, Habib AS. A double-blind, placebo-controlled trial of four fixed rate infusion regimens of phenylephrine for hemodynamic support during spinal anesthesia for cesarean delivery. Anesth Analg. 2010;111(5):1221-1229.
    1. Apfelbaum JL, Hawkins JL, Agarkar M, et al. Practice guidelines for obstetric anesthesia. an updated report by the american society of anesthesiologists task force on obstetric anesthesia and the society for obstetric anesthesia and perinatology. Anesthesiology. 2016;124(2):270-300.
    1. Kinsella SM, Carvalho B, Dyer RA, et al. International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia. Anaesthesia. 2018;73(1):71-92.
    1. Higgins N, Fitzgerald PC, van Dyk D, et al. The effect of prophylactic phenylephrine and ephedrine infusions on umbilical artery blood pH in women with preeclampsia undergoing cesarean delivery with spinal anesthesia: a randomized, double-bind trial. Anesth Analg. 2018;126(6):1999-2006.
    1. Dyer R, Reed A, van Dyk D, et al. Hemodynamic effects of ephedrine, phenylephrine, and the coadministration of phenylephrine with oxytocin during spinal anesthesia for elective cesarean delivery. Anesthesiology. 2009;111(4):753-765.

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