Reducing Spinal Hypotension During Cesarean Delivery with Glycopyrrolate: A meta-analysis
Abstract Number: SA-26
Abstract Type: Original Research
Hypotension is a common and important complication associated with spinal anesthesia for cesarean delivery.(1) The objective of this meta-analysis was to determine if prophylactic glycopyrrolate administration reduces the hypotensive changes associated with spinal anesthesia.
A literature search (Medline, Embase, CINAHL, Scopus and Pubmed) was performed to identify randomized controlled trials investigating the effect of glycopyrrolate on spinal-induced hypotension for cesarean delivery. Primary outcomes were incidence of hypotension and dose of vasopressor used (ephedrine equivalent). Secondary outcomes included: incidence of bradycardia, incidence of nausea and vomiting and incidence of dry mouth. Risk ratios (RR), odd ratios (OR) and weighted mean differences (WMD) were calculated using random effects modeling with 95% confidence interval.
Five RCTs met our inclusion criteria. A total of 311 patients were recruited in all study groups: 153 patients in the glycopyrrolate group and 158 in the control group. The incidence of spinal-induced hypotension was no different with prophylactic glycopyrrolate administration compared to placebo controls (RR 0.93 [0.71, 1.21]; p=0.59), but the dose of ephedrine required to treat hypotension was significantly reduced in the glycopyrrolate group (WMD -5.3 mg[-8.80 mg, -1.79 mg]; p=0.003). The glycopyrrolate group had a lower incidence of bradycardia (RR 0.15 [0.03, 0.80]; p=0.03), and the maximal HR achieved was significantly higher compared to the control group (MD 15.85 [7.90, 23.81]; p<0.0001). The incidences of nausea and vomiting, and dry mouth were similar between both groups with OR 0.7 [0.2, 2.45]; p=0.58 and RR 1.56 [0.10, 23.24]; p=0.75 respectively.
Prophylactic glycopyrrolate administration for cesarean delivery does not affect the incidence of spinal-induced hypotension, but does result in a modest reduction in vasopressor requirements and incidence of bradycardia. Utilizing glycopylorrate for cesarean delivery under spinal anesthesia should be considered. However larger, adequately powered studies investigating side-effects are still needed before routine use can be recommended.
1. Stewart A et al. The dose-dependent effects of phenylephrine for elective cesarean delivery under spinal anesthesia. Anesth Analg 2010; 111: 1230 -1237.