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 aim of this study to investigate whether critical respiratory events (CREs) that described in a modified Murphy’s criteria are significantly associated with residual neuromuscular blockade (RNMB).Method: A prospective cohort study from January to March 2017 from a tertiary hospital from Saudi Arabia for thirty adult patients over 18 years old scheduled for elective surgery under general anaesthesia with neuromuscular blocking drugs (NMBDs) 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: 26 (86.7%) patients out of thirty in the study has received Rocuronium as NMBDs while 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 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.