Comparison of 3 Rates for the Continuous Infusion of Mivacurium During Ambulatory Vitreoretinal Surgery Under General Anesthesia: A Prospective, Randomized, Controlled Clinical Trial

Purpose

Mivacurium, the shortest-acting benzylisoquinoline nondepolarizing neuromuscular blocker used in clinical practice, is suitable for short-term ambulatory operations under general anesthesia. We investigated the neuromuscular blockade effect of different maintenance doses of mivacurium during ambulatory vitreoretinal surgery under general anesthesia and tried to determine the appropriate maintenance dose.

Patients and Methods

Ninety-nine patients undergoing general anesthesia for elective ambulatory vitreoretinal surgery were randomly divided into three groups using the random number table method. Patients received three maintenance doses of mivacurium during surgery as follows: 3 μg/(kg·min) in group M1 (n = 33), 6 μg/(kg·min) in group M2 (n = 33), and 9 μg/(kg·min) in group M3 (n = 33). The primary outcome was the time from mivacurium withdrawal to a train-of-four stimulation ratio (TOFr) ≥ 0.9, and the secondary outcomes were the time from mivacurium withdrawal to TOFr ≥ 0.7, extubation time, incidence of TOFr < 0.9 after surgery and neuromuscular block effect.

Results

The time from mivacurium withdrawal to TOFr ≥ 0.9 and to TOFr ≥ 0.7 was significantly longer in group M3 than in groups M1 and M2 (25.6±7.2 min vs 16.4±5.9 min and 18.6±5.3 min, P < 0.001; 22.1±6.3 min vs 13.6 ± 5.8 min and 15.5 ± 4.8 min; P < 0.001, respectively). There was a significant difference in the extubation time, the incidence of TOFr < 0.9 during extubation and upon leaving the operating room between group M3 and group M1 (all P < 0.05), but there was no such significant difference between group M2 and group M1 (all P > 0.05). The intraoperative depth of neuromuscular blockade in the three groups was significantly different, with 69.7% shallow block in group M1, 75.8% moderate block in group M2 and 63.6% deep block in group M3 (P < 0.001). One patient in group M1 experienced slight body movement during the operation.

Conclusion

An intraoperative continuous infusion of 6 μg/(kg·min) mivacurium can not only achieve good postoperative recovery but also provide a satisfactory neuromuscular blockade effect during surgery, and this maintenance dose is suitable for neuromuscular blockade during ambulatory vitreoretinal surgery.

Comparative Analysis of the Anesthesia Effect of Cisatracurium Besylate and Mivacurium Chloride Otolaryngology Surgery

Objective

The aim is to investigate and compare the anesthesia effect of cisatracurium besylate and mivacurium chloride otolaryngology surgery.

Materials and Methods

108 patients who underwent ENT surgery under general anesthesia in our hospital from November 2021 to March 2022 were recruited for retrospective analysis, in which patients in the experimental group A were anesthetized with cisatracurium besylate and patients in the experimental group B were anesthetized with mivacurium, and the anesthetic effects and recovery of the two groups were compared and analyzed.

Results

There was no significant difference in mean arterial pressure, heart rate, and pulse oximetry levels between the two groups at the six time points of admission, anesthesia induction, intubation, end of operation, recovery of consciousness, and extubation (all P > 0.05). The train of four stimulation values at end of operation, recovery of consciousness, and extubation were significantly higher than those of the experimental group A (all P > 0.05). The recovery time of self-consciousness, extubation time, and eye-opening time of the experimental group B were significantly shorter than those of the experimental group A, and the occurrence of agitation was significantly less than that of the experimental group A (all P > 0.05). The total incidence of adverse conditions in the experimental group B was significantly lower than that in the experimental group A (P > 0.05).

Conclusion

Compared with cisatracurium besylate in otolaryngology surgery, mivacurium chloride anesthesia offers a promising route with respect to less impact on hemodynamics, faster postoperative recovery, absence of the accumulation of neuromuscular blockade, less adverse reactions, and higher safety.

Neuromuscular-blocking agents for tracheal intubation in pediatric patients (0-12 years): A systematic review and meta-analysis

BACKGROUND

The benefit of using neuromuscular-blocking agents to facilitate tracheal intubation in pediatric patients remains unclear due to variations in design, treatments, and results among trials. By combining the available evidence, we aimed to establish whether scientific findings are consistent and can be generalized across various populations, settings, and treatments.

METHODS

A systematic search for randomized controlled trials, related to the use of neuromuscular-blocking agents for tracheal intubation in American Society of Anesthesiologists class I-II participants (0-12 years), was performed. We considered all randomized controlled trials that studied whether intubation conditions and hemodynamics obtained by using neuromuscular-blocking agents were equivalent to those that were achieved without neuromuscular-blocking agents. We combined the outcomes in Review Manager 5.3 (RevMan, The Cochrane Collaboration) by pairwise random-effects meta-analysis using a risk ratio (RR) for intubation conditions and mean difference for hemodynamic values (mean [95% Confidence Intervals]). Heterogeneity among trials was explored using sensitivity analyses.

RESULTS

We identified 22 eligible randomized controlled trials with 1651 participants. Overall, the use of a neuromuscular-blocking agent was associated with a clinically important increase in the likelihood of both excellent (RR = 1.41 [1.19-1.68], I²  = 76%) and acceptable (RR = 1.13 [1.07-1.19], I²  = 68%) intubating conditions. There is strong evidence that both unacceptable intubation conditions (RR = 0.35 [0.22-0.46], I²  = 23%) and failed first intubation attempts (RR = 0.25 [0.14-0.42], I²  = 0%) were less likely to occur when a neuromuscular-blocking agent was used compared with when it was not. Higher systolic or mean arterial pressures (mean difference = 13.3 [9.1-17.5] mm Hg, I²  = 69%) and heart rates (mean difference = 15.9 [11.0-20.8] beats/min, I²  = 75%) as well as a lower incidence of arrhythmias were observed when tracheal intubation was facilitated by neuromuscular-blocking agents.

CONCLUSION

The use of a neuromuscular-blocking agent during light-to-moderate depth of anesthesia can improve the quality as well as the success rate of tracheal intubation and is associated with better hemodynamic stability during induction of anesthesia.