Forty years of neuromuscular monitoring and postoperative residual curarisation: a meta-analysis and evaluation of confidence in network meta-analysis.

Background: The reported incidence of postoperative residual curarisation (PORC) is still unacceptably high. The capacity of intraoperative neuromuscular monitoring (NMM) to reduce the incidence of PORC has yet to be established from pooled clinical studies. We conducted a meta-analysis of data from 1979 to 2019 to reanalyse this relationship.

Methods: English language, peer-reviewed, and operation room adult anaesthesia setting articles published between 1979 and 2019 were searched for on PubMed, Cochrane Central Register of Controlled Trials, ISI-WoK, and Scopus. The primary outcome was PORC incidence as defined by an at- or post-extubation train-of-four ratio (TOFR) of lower than 0.7, 0.9, or 1.0. Additional collected variables included the duration of action of neuromuscular blocking agents (NMBAs) used, sugammadex or neostigmine use, and the technique of anaesthesia maintenance.

Results: Fifty-three studies (109 study arms, 12 664 patients) were included. The pooled PORC incidence associated with the use of intermediate duration NMBAs and quantitative NMM was 0.115 (95% confidence interval [CI], 0.057-0.188). This was significantly lower than the PORC rate for both qualitative NMM (0.306; 95% CI, 0.09-0.411) and no NMM (0.331; 95% CI, 0.234-0.435). Anaesthesia type did not significantly affect PORC incidence. Sugammadex use was associated with lower PORC rates. The GRADE global level of evidence was very low and the refined assessment of the network meta-analysis by means of a confidence in network meta-analysis raised concerns on within- and across-study bias.

Conclusions: Quantitative NMM outperforms both subjective and no NMM monitoring in reducing PORC as defined by a TOFR of <0.9.