Quantitative Neuromuscular Monitoring With Train-of-Four Ratio During Elective Surgery: A Prospective, Observational Study

Postoperative residual neuromuscular block (PRNB) is a serious problem that can cause death after surgery. It was aimed to evaluate the adequacy of neuromuscular block (NMB) during endotracheal intubation and the adequacy of neuromuscular recovery during clinically extubation decision and follow-up with the train-of-four ratio (TOFR) using quantitative monitoring.This study has a prospective-observational single-blind study design. A total of 205 adult patients who underwent elective surgery, who had American Society of Anesthesiologists physical statuses I to III, and who were intubated with neuromuscular blocking agent under general anesthesia were included in the study. Train-of-four ratio measurements were provided single-blindly by another anesthesiologist outside the team. The TOFRs were measured at the time of intubation (TOFRind), before reversal agent administration (TOFRpre-rev) and after (TOFRpost-rev), at the time of extubation (TOFRext), and on admission to the postoperative care unit (TOFRPACU). If clinical signs of PRNB appeared, the recovery protocol was applied and then TOFRrec was measured. Postoperative respiratory complications were also evaluated for the first 24 hours after surgery.Endotracheal intubation was performed in 41.5% of the patients (n = 85) without adequate NMB. In 48.8% (n = 100) of the patients, adequate recovery (TOFRext ˂0.9) was not available at the time of extubation. Adequate TOFRPACU rate was found to be significantly higher in those who did not receive additional neuromuscular blocking agent doses (P < 0.001). In the recovery protocol, low-dose sugammadex administered to patients with clinical signs of PRNB significantly increased the TOFRrec rate compared with neostigmine (P ˂ 0.001). The first 24 hours, postoperative respiratory complication rate was 5.4% (n = 11), and the most common hypoxemia was observed.Approximately half of the patients are intubated without sufficient NMB and extubated without sufficient neuromuscular recovery. This suggests that routine use of quantitative neuromuscular monitoring is necessary for patient safety.