Relationship between muscle mass ratio and rocuronium dose required for maintaining deep neuromuscular blockade: A prospective observational study

BACKGROUND

Deep neuromuscular blockade (NMB) has benefits in various surgical procedures, however, precise quantitative neuromuscular monitoring is crucial for its proper maintenance and recovery. Neuromuscular blocking agent dosage relies on actual body weight (ABW), but this varies among individuals. Therefore, this study hypothesizes that there is a correlation between the rocuronium requirement for deep NMB and muscle mass ratio measured by bioelectric impedance analysis.

METHODS

Ninety adult female patients undergoing laparoscopic operation were enrolled in this study. Muscle and fat masses were assessed using a body composition analyser. Deep NMB, defined as a post-tetanic count of 1-2, was maintained through the continuous infusion of rocuronium. The primary outcome involves determining the correlation between the rocuronium dose required for deep NMB and the muscle mass ratio. Conversely, secondary outcomes included assessing the relationship between the rocuronium dose for deep NMB and fat mass ratio, and ABW. Additionally, we investigated their relationship with rocuronium onset time and profound blockade duration.

RESULTS

No relationship was observed between the muscle mass ratio and rocuronium dose required for maintaining deep NMB (r = 0.059 [95% CI = 0.153-0.267], p = 0.586). Fat mass ratio and ABW showed no correlation with the rocuronium dose, whereas rocuronium onset time was positively correlated with muscle mass ratio (r = 0.327) and negatively correlated with fat mass ratio (r = -0.302), respectively. Profound blockade duration showed no correlation with any of the assessed variables.

CONCLUSIONS

No correlation was detected between muscle mass ratio and the rocuronium dose required to achieve deep NMB.

Perioperative neuromuscular blockade. 2020 update of the SEDAR (Sociedad Española de Anestesiología y Reanimación) recommendations

We present an update of the 2020 Recommendations on neuromuscular blockade of the SEDAR. The previous ones dated 2009. A modified Delphi consensus analysis (experts, working group, and previous extensive bibliographic revision) 10 recommendations were produced1: neuromuscular blocking agents were recommended for endotracheal intubation and to avoid faringo-laryngeal and tracheal lesions, including critical care patients.2 We recommend not to use neuromuscular blocking agents for routine insertion of supraglotic airway devices, and to use it only in cases of airway obstruction or endotracheal intubation through the device.3 We recommend to use a rapid action neuromuscular blocking agent with an hypnotic in rapid sequence induction of anesthesia.4 We recommend profound neuromuscular block in laparoscopic surgery.5 We recommend quantitative monitoring of neuromuscular blockade during the whole surgical procedure, provided neuromuscular blocking agents have been used.6 We recommend quantitative monitoring through ulnar nerve stimulation and response evaluation of the adductor pollicis brevis, acceleromyography being the clinical standard.7 We recommend a recovery of neuromuscular block of at least TOFr ≥ 0.9 to avoid postoperative residual neuromuscular blockade.8 We recommend drug reversal of neuromuscular block at the end of general anesthetic, before extubation, provided a TOFr ≥ 0.9 has not been reached.9 We recommend to choose anticholinesterases for neuromuscular block reversal only if TOF≥2 and a TOFr ≥ 0.9 has not been attained.10 We recommend to choose sugammadex instead of anticholinesterases for reversal of neuromuscular blockade induced with rocuronium.

Effects of depth of neuromuscular blockade on the BIS-guided propofol requirement: A randomized controlled trial

BACKGROUND

Deep neuromuscular blockade is considered beneficial for improving the surgical space condition during laparoscopic surgery. Adequacy of the surgical space condition may affect the anesthetists' decision regarding titration of depth of anesthesia. We investigated whether deep neuromuscular blockade reduces the propofol requirement under bispectral index monitoring compared to moderate neuromuscular blockade.

METHODS

Adult patients undergoing elective laparoscopic colorectal surgery were randomly allocated to a moderate or deep group. A train-of-four count of 1-2 in the moderate group, and a post-tetanic count of 1-2 in the deep group, were maintained by continuous infusion of rocuronium. The induction and maintenance of anesthesia were achieved by target-controlled infusion of propofol and remifentanil. The dose of propofol was adjusted to maintain the bispectral index in the range of 40-50. The remifentanil dose was titrated to maintain the systolic blood pressure to within 20% of the ward values.

RESULTS

A total of 82 patients were included in the analyses. The mean±SD dose of propofol was 7.54 ± 1.66 and 7.42 ± 1.01 mg·kg-1·h-1 in the moderate and deep groups, respectively (P = .104). The mean±SD dose of remifentanil was 4.84 ± 1.74 and 4.79 ± 1.77 μg kg-1 h-1 in the moderate and deep groups, respectively (P = .688). In comparison to the moderate group, the deep group showed significantly lower rates of intraoperative patient movement (42.9% vs 22.5%, respectively, P = .050) and additional neuromuscular blocking agent administration (76% vs 53%, respectively, P = .007). Postoperative complications, including pulmonary complications, wound problems and reoperation, were not different between the two groups.

CONCLUSION

Deep neuromuscular blockade did not reduce the bispectral index-guided propofol requirement compared to moderate neuromuscular blockade during laparoscopic colon surgery, despite reducing movement of the patient and the requirement for a rescue neuromuscular blocking agent.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT03890406).

Effects of magnesium on the dose of rocuronium for deep neuromuscular blockade: A randomised controlled trial

BACKGROUND

Magnesium is known to enhance the effect of rocuronium, but the extent is not quantified.

OBJECTIVES

We aimed to quantify the effect of magnesium on the dose of rocuronium for deep neuromuscular blockade.

DESIGN

A randomised controlled study.

SETTING

A single tertiary care hospital.

PATIENTS

Seventy males scheduled to undergo robot-assisted laparoscopic prostatectomy, aged between 20 and 80 years with American Society of Anesthesiologists physical status classification 1 or 2, were enrolled.

INTERVENTIONS

Patients were randomised to either the magnesium group or control group. The magnesium group were infused with 50 mg kg-1 of magnesium, followed by a continuous intra-operative infusion at 15 mg kg-1 h-1 while the control group were infused with the same volumes of 0.9% saline. Deep neuromuscular blockade was maintained with a continuous infusion of rocuronium and was reversed using sugammadex.

MAIN OUTCOME MEASURES

The primary outcome was the dose of rocuronium administered to maintain deep neuromuscular blockade. The secondary outcomes were recovery time, defined as the time from the administration of sugammadex to train-of-four ratio 0.9, and the incidence of postoperative nausea and vomiting.

RESULTS

The dose of rocuronium administered to maintain deep neuromuscular blockade was significantly lower in the magnesium group (7.5 vs. 9.4 μg kg-1 min-1, P = 0.01). There was no difference in recovery time or the incidence of nausea and vomiting.

CONCLUSION

Magnesium reduced the dose of rocuronium required for deep neuromuscular blockade by approximately 20% without affecting the recovery time after administration of sugammadex.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04013243.