Efficacy and safety of neostigmine for neuromuscular blockade reversal in patients under general anesthesia: a systematic review and meta-analysis

Background: Since the antagonistic effect of neostigmine on muscle relaxation is still controversial, this study aimed to evaluate the efficacy and safety of neostigmine for the reversal of neuromuscular blockade in patients recovering from general anesthesia. Methods: Multiple databases, including PubMed, Web of Science, the Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI), were electronically searched up to August 2021. Relevant studies on the use of neostigmine for neuromuscular blockade reversal in patients under general anesthesia were retrieved. Two reviewers independently screened and extracted data from the retrieved studies, and assessed their risk of bias. Review Manager 5.2 was used to evaluate the efficacy and safety of neostigmine based on the included articles. Heterogeneity and related subgroup, sensitivity, and bias analyses were carried out. Results: The analysis included 14 studies involving 2,109 patients, including 1,209 in the neostigmine group and 990 in the control group. Results from the random-effects model showed that neostigmine reduced the length of stay in the post-anesthesia care unit [mean difference (MD) =-17.73, 95% Confidential interval (CI): - 22.06 to - 13.41, P<0.0001], the time to recovery of train-of-four ratio =0.9 (MD =-16.60, 95% CI: -23.67 to -9.52, P<0.0001), and the extubation time (MD =-16.69, 95% CI: -28.22 to -5.17, P=0.005). However, no difference was observed in adverse events between the neostigmine and control groups [odds ratio (OR) =0.97, 95% CI: 0.84-1.12, P=0.71]. Subgroup analyses adjusted for the dosage of neostigmine had no effect on the above results. Conclusions: Neostigmine can effectively and safely enhance neuromuscular recovery from nondepolarizing muscle relaxants in patients under general anesthesia.

Automated summary

Neostigmine has been shown to effectively reduce post-anesthesia care unit stay, time to recovery of train-of-four ratio =0.9, and extubation time in patients recovering from general anesthesia. However, there were no significant differences in adverse events between the neostigmine and control groups. Subgroup analyses based on neostigmine dosage did not affect the overall results. Neostigmine can safely enhance neuromuscular recovery from nondepolarizing muscle relaxants in patients under general anesthesia.