The association between residual neuromuscular blockade (RNMB) and critical respiratory events: a prospective cohort study

Abstract

Background Inadequate neuromuscular recovery might impair pulmonary function among adult patients who undergo general anaesthesia and might thus contribute to critical respiratory events in the post-anaesthesia care unit (PACU). The pilot study aims to understand the baseline incidence of residual neuromuscular blockade (RNMB) and postoperative critical respiratory events (CREs), which are described in a modified Murphy’s criteria in the PACU. Method This is a prospective cohort study from January to March 2017 from a tertiary hospital in Saudi Arabia with thirty adult patients over 18 years old scheduled for elective surgery under general anaesthesia with neuromuscular blocking drugs (NMBDs) who were enrolled in the study. The Mann-Whitney U tests, chi-square tests and independent-samples T tests were used. The train-of-four (TOF) ratios were measured upon arrival in the PACU by using acceleromyography with TOF-Scan. Subjects’ demographics, perioperative data and the occurrence of postoperative CREs in the PACU were recorded. Results Twenty-six (86.7%) patients out of thirty in the study have received rocuronium as NMBDs whilst neostigmine as a reversal drug with only 23 (76.7%). The incidence of RNMB (TOF ratio < 0.9) was in 16 patients (53.3%). The incidence of RNMB was significantly higher in female patients (p = 0.033), in patients who had not undergone quantitative neuromuscular monitoring before extubation (p = 0.046) and in patients with a shorter duration of surgery (p = 0.001). Postoperative CREs occurred in twenty patients (66.7%), and there were significantly more of these CREs among patients with RNMB (p = 0.001). In addition, a statistically significant difference was observed in the occurrence of CREs according to body mass index (p = 0.047). Conclusion This research showed that RNMB is a significant contributing factor to the development of critical respiratory events during PACU stay. Therefore, routine quantitative neuromuscular monitoring is recommended to reduce the incidence of RNMB.

2023 American Society of Anesthesiologists Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade: A Report by the American Society of Anesthesiologists Task Force on Neuromuscular Blockade

“…Patients with adequate spontaneous recovery to train-offour ratio greater than or equal to 0.9 can be identified only with quantitative monitoring, and these patients do not require pharmacological antagonism. The body of evidence included 16 studies (10 randomized controlled trials, 3,12,[39][40][41]47,[169][170][171][172] 2 before-after design, 44,46 3 prospective cohort studies, 42,45,48 and 1 retrospective cohort study 43 ) comparing the effects of quantitative monitoring with qualitative assessment or clinical assessment on patient outcomes. Studies enrolled a median of 135 participants (range, 30 to 17,150).…”

“…Residual Neuromuscular Blockade. A total of five randomized controlled trials 3,12,[39][40][41] and three observational studies [42][43][44] reported lower incidences of residual neuromuscular blockade with quantitative monitoring compared with qualitative assessment or clinical assessment (supplemental tables S8 and S9, http://links.lww.com/ALN/C928). Although both train-of-four ratio thresholds and place (operating room or PACU) where residual neuromuscular blockade were assessed differently across the studies, there is general consistency in the estimated risk ratios.…”

“…Although both train-of-four ratio thresholds and place (operating room or PACU) where residual neuromuscular blockade were assessed differently across the studies, there is general consistency in the estimated risk ratios. A prospective study 42 and a retrospective cohort study 43 included comparisons of quantitative monitoring with clinical assessment alone; a before–after design 44 compared quantitative monitoring with peripheral nerve stimulator or clinical assessment—all defined residual neuromuscular blockade as a train-of-four ratio less than 0.9 assessed in the PACU. Recognizing the clinical and methodological diversity across studies, given the consistent effects reported, the results were pooled both for randomized controlled trials alone (pairwise) and in a network meta-analysis.…”

“…The body of evidence included 16 studies (10 randomized controlled trials, 3,12,39–41,47,169–172 2 before–after design, 44,46 3 prospective cohort studies, 42,45,48 and 1 retrospective cohort study 43 ) comparing the effects of quantitative monitoring with qualitative assessment or clinical assessment on patient outcomes. Studies enrolled a median of 135 participants (range, 30 to 17,150).…”

“…The body of evidence enrolling adults included 191 studies (133 randomized controlled trials, 4,59–90,92,95,98–104,110–114,118–127,132–141,145–148,155–157,163,173–181,206–254 11 nonrandomized trials, 17,128,142,182–184,191,255–258 45 cohort studies, 15,42,86,91,93,94,96,97,105–109,116,117,129–131,143,144,186–190,227,259–277 and 2 before–after designs 115,168 ) evaluating efficacy and safety of antagonist drugs for neuromuscular blockade. The randomized controlled trials enrolling only adults had a median of 88 participants (range, 16 to 350).…”