Propofol decreased the etomidate-induced myoclonus in adult patients: a meta-analysis and systematic review

Myoclonus is one of the main complications of etomidate anesthesia, which would develop into serious consequences during surgery. The present analysis was performed to evaluate systematically the effect of propofol on preventing etomidate-induced myoclonus in adult patients.

Systematic electronic literature search was performed in the databases PubMed, Cochrane Library, OVID, Wanfang and China National Knowledge Infrastructure (CNKI) from inception to May 20, 2021, without any language restrictions. All randomized controlled trials evaluating the efficacy of propofol on preventing etomidate-induced myoclonus were enrolled. The primary outcome included the incidence and degree of etomidate-induced myoclonus.

1,420 patients (with 602 received etomidate anesthesia and 818 received propofol plus etomidate anesthesia) from 13 studies were eventually included. Whatever the intravenous propofol dose for anesthesia induction 0.8-2 mg/kg (RR:4.04, 95% CI [2.42,6.74] p<0.0001, I2=56.5%), or the dose of propofol for anesthesia induction 0.5-0.8 mg/kg (RR:3.26, 95% CI [2.03,5.22] p<0.0001, I2=0%), or the dose of propofol for anesthesia induction 0.25-0.5mg/kg (RR:1.68, 95% CI [1.1,2.56] p=0.0160, I2=0%), combination of propofol and etomidate could significantly decrease the occurrence of etomidate-related myoclonus (RR=2.99, 95% CI [2.40, 3.71] p<0.0001, I2=43.4%), compared with etomidate alone. In addition, propofol plus etomidate attenuated the incidence of mild (RR:3.40, 95% CI [1.7,6.82] p=0.0010, I2=54.3%), moderate (RR:5.4, 95% CI [3.01, 9.67] p<0.0001, I2=12.6%), severe (RR:4.15, 95% CI [2.11, 8.13] p<0.0001, I2=0%) of etomidate-induced myoclonus without adverse effects except for the increased incidence of pain on injection (RR:0.47, 95% CI [0.26, 0.83] p=0.0100, I2=41.5%) compared with etomidate alone.

The meta-analysis currently generates the evidence of combination of propofol with the dosage of 0.25-2 mg/kg and etomidate can alleviate the occurrence and severity of etomidate-induced myoclonus, with decreased incidence of postoperative nausea and vomiting (PONV) and comparative side effects of hemodynamic and respiratory depression of patients in comparison with etomidate alone.