A Comparison of Prophylactic Intravenous Glycopyrrolate and Ephedrine in the Prevention of Spinal Induced Maternal Hypotension during Caesarean Section

Abstract

Background: Spinal anaesthesia is complicated by hypotension and bradycardia. There are many risk factors for bradycardia in parturients who present for caesarean section. Due to the different pathophysiology of bradycardia, prophylactic administration of a vagolytic (glycopyrrolate) may however counter bradycardia thereby maintains blood pressure. Ephedrine is gradually falling out of favour because of the associated tachyarrhythmia and foetal acidosis. This study compared the effect of preoperative administration of intravenous glycopyrrolate and ephedrine on spinal induced maternal hypotension.
Patients and Methods: Fifty patients scheduled for elective C/S were randomized into two groups of 25 each. Group G received 0.2mg of glycopyrrolate while Group E received 6mg of ephedrine immediately before spinal anaesthesia was established. Intrathecal bupivacaine 2.0ml with 25μg fentanyl was injected into the subarachnoid space in both groups. Primary outcome was the mean systolic blood pressure and incidence of hypotension. The secondary outcomes were the total amount of rescue ephedrine used, incidence of nausea-vomiting and side effects (dry mouth, tachycardia).
Results: There was a statistical difference in the mean intraoperative systolic between per-operatively administered intravenous glycopyrrolate and ephedrine, (p = 0.001) but there was no difference in the incidence of hypotension, (p = 0.115) pulse rate and the total amount of rescue vasopressor used (p value 0.667)
Conclusion: There was a difference in the mean maternal intraoperative systolic blood pressure between pre-operatively administered intravenous glycopyrrolate and ephedrine. This has clinical consequence, in that glycopyrrolate may be used in place of ephedrine which is gradually falling out of favour or when it's not available.

Keywords: Prophylactic glycopyrrolate and ephedrine, maternal blood pressure, pulse rate, caesarean section.