Prevalence and Risk Factors of Postoperative Residual Curarization in Patients Arriving at Postanesthesia Care Unit after General Anesthesia: A Prospective Cohort Study

Abstract

Background: Postoperative residual curarization (PORC) following the use of neuromuscular blocking drugs (NMBDs) remains a significant problem. The purpose of this study was to determine the prevalence and risk factors of PORC in patients who were admitted to postanesthesia care unit (PACU) after general anesthesia during our routine clinical practice.Methods: This was a prospective, observational cohort study. Patients who were admitted to PACU after general anesthesia were enrolled. Neuromuscular function was monitored using acceleromyography and train-of-four (TOF) stimulation. A TOF ratio of less than 0.9 was defined as having PORC. Multivariate Logistic regression analysis was performed to identify risk factors of PORC.Results: A total of 542 patients completed the study. PORC occurred in 30.6% (166/542) of patients. Increasing age (odds ratio [OR] 1.211, 95% confidence interval [CI] 1.068-1.374, P=0.003), combined use of two different non-depolarizing NMBDs during surgery (OR 1.693, 95% CI 1.138-2.520, P=0.009) and hypothermia at PACU arrival (OR 1.778, 95% CI 1.043-3.032, P=0.035) were associated with increased risk of PORC, whereas administration of neostigmine at the end of surgery (OR 0.341, 95% CI 0.164-0.709, P=0.004) and prolonged time interval from last dose of NMBDs to PACU arrival (OR 0.326, 95% CI 0.215-0.496, P<0.001) were associated with decreased risk of PORC. Patients with PORC at PACU arrival had prolonged PACU stay, increased occurrence of adverse events during PACU stay and increased rate of PORC at PACU discharge.Conclusions: PORC was common in patients who were admitted to PACU after general anesthesia. Increasing age, combined use of two different non-depolarizing NMBDs during surgery and hypothermia at PACU arrival were associated with increased risk of PORC. Citation: Min Xie, Dong-Xin Wang, Zhi-Yu Geng. Prevalence and risk factors of postoperative residual curarization in patients arriving at postanesthesia care unit after general anesthesia: a prospective cohort study. J Anesth Perioper Med 2014; 1: 72-8. doi: 10.24015/JAPM.2014.0012This is an open-access article, published by Evidence Based Communications (EBC). This work is licensed under the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution, and reproduction in any medium or format for any lawful purpose. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.