Incidence of postoperative residual neuromuscular blockade in the postanaesthesia care unit: an observational multicentre study in Portugal.

CONTEXT: Residual neuromuscular blockade still presents despite the use of intermediate duration muscle relaxants and is a risk factor for postoperative morbidity. OBJECTIVE: To determine the incidence of incomplete postoperative neuromuscular recovery from anaesthesia in a postanaesthesia care unit. DESIGN: Multicentre observational study. SETTING: Public Portuguese hospitals. PATIENTS: Adult patients scheduled for elective surgery requiring general anaesthesia with neuromuscular blocking agents. MAIN OUTCOME MEASURES: An independent anaesthesiologist measured neuromuscular transmission by the TOF-Watch SX acceleromyograph. Train-of-four ratios at least 0.9 and less than 0.9 were assessed as complete and incomplete neuromuscular recovery following general anaesthesia, respectively. RESULTS: The study population consisted of 350 patients [134 men and 216 women, mean (SD) age 54.3 (15.9) years]. Ninety-one patients had a train-of-four ratio less than 0.9 on arrival in the postanaesthesia care unit, an incidence of residual neuromuscular blockade of 26% [95% confidence interval (CI) 21 to 31%]. The most frequent neuromuscular blockers were rocuronium (44.2%) and cisatracurium (32%). A neuromuscular block reversal agent was used in 66.6% of the patients (neostigmine in 97%). The incidence of residual neuromuscular blockade in patients receiving reversal agents was 30% (95% CI 25 to 37%). There were no statistically significant differences in the occurrence of residual blockade relating to the neuromuscular blocker used, although higher percentages were observed for cisatracurium (32.4%) and vecuronium (32%) compared with atracurium (23.6%) and rocuronium (20.8%). Incomplete neuromuscular recovery was significantly more frequent among patients who had received a reversal agent (30.5 vs. 17.1%, P = 0.01). Incomplete neuromuscular recovery was more frequent in patients given propofol than in those exposed to sevoflurane (26.2 vs. 14.3%). CONCLUSION: The incidence of incomplete neuromuscular recovery of 26% confirms that it is relatively frequent in the postoperative period and calls attention to the dimension of this problem in Portugal.

Incidence of postoperative residual neuromuscular blockade - A multicenter, observational study in Portugal (INSPIRE 2).

Background: Although the use of neuromuscular blocking agents (NMBAs) optimizes surgical conditions and facilitates tracheal intubation, it can lead to residual neuromuscular blockade (RNMB), with postoperative complications. This study aimed to assess RNMB incidence and management in Portugal. Methods: Prospective observational study of patients admitted for elective surgery requiring general anesthesia with nondepolarizing NMBAs between July 2018 and July 2019 at 10 Portuguese hospitals. The primary endpoint was the proportion of patients arriving at postanesthesia care unit (PACU) with a TOF ratio <0.9. Results: A total of 366 patients were included, with a median age of 59 years, and 89.1% classified as ASA II or III. Rocuronium was the most used NMBA (99.5%). A total of 96.2% of patients received a reversal agent, 96.6% of which sugammadex and 3.4% neostigmine. Twenty patients displayed a TOF ratio <0.9 at PACU arrival, representing an RNMB incidence of 5.5% (95% CI, 3.1%-7.8%). Only two patients displayed a TOF ratio <0.7. RNMB incidence was 16.7% with neostigmine and 5.3% with sugammadex (P = .114). In patients with intraoperative neuromuscular blockade (NMB) monitoring, RNMB incidence was 5% (95% CI, 2%-8%), which varied significantly according to the type of monitoring (P = .018). Incidence of adverse events was 3.3% (2 severe and 10 moderate). Conclusions: The reported overall incidence of 5.5% is numerically lower than results from similar observational studies. An appropriate pharmacological neuromuscular reversal strategy, guided by quantitative neuromuscular monitoring, has the potential to achieve even better results, converting RNMB from an unusual to a very rare or even inexistent event.

Efeito da alopregnanolona sobre o desenvolvimento da tolerância rápida ao efeito ansiolítico do etanol / Effect of allopregnanolone on development of rapid tolerance to the anxiolytic effect of ethanol

Estudos prévios têm mostrado que o neuroesteróideis o pregnanolona bloqueou o desenvolvimento datolerância rápida ao efeito ansiolítico do etanol. O objetivo do presente estudo foi investigar a influência da alopregnanolona sobre o desenvolvimento da tolerância rápida ao efeito ansiolítico do etanol em camundongos (ratones). No primeiro experimento, o objetivo foi investigar o efeito da alopregnanolona (0.05, 0.10 ou0.20 mg/kg) sobre a tolerância rápida ao etanol (1.5 g/kg). No segundo experimento, o efeito do flumazenil (2.0 mg/kg) sobre a influência da alopregnanolona na tolerância rápida ao etanol foi investigado. Os resultados mostram que o tratamento prévio com alopregnanolona interferiun o desenvolvimento da tolerância rápida ao efeito ansiolítico etanol. Além disso (Además), o tratamento prévio com flumazenil não interferiu (no interfirió) na ação inibitória da alopregnanolona sobre o desenvolvimento da tolerância rápida ao etano.