Incidence of insufficient intraoperative neuromuscular paralysis. A retrospective registry analysis

Effect of neuromuscular block on surgical conditions during laparoscopic surgery in neonates and small infants: A randomised controlled trial

BACKGROUND

Neuromuscular block (NMB) is routinely used in paediatric and adult anaesthesia to facilitate endotracheal intubation and optimise surgical conditions. However, there are limited data regarding NMB and optimising the conditions for laparoscopic surgery in neonates and small infants.

OBJECTIVE

The goal of this study was to determine the effect of NMB on the conditions for laparoscopic surgery in neonates and small infants.

DESIGN

A randomised controlled trial.

SETTING

Single-centre Children's Hospital, conducted from November 2021 to December 2022.

PATIENTS

One hundred and two ASA I-II neonates and small infants aged up to 60 weeks postmenstrual age who were scheduled to undergo an elective laparoscopic Ladd's procedure were included in the study.

INTERVENTIONS

Patients were randomised into three groups: no NMB group, shallow NMB group and moderate NMB group. Each group was given different doses of rocuronium to achieve the target depth of NMB.

MAIN OUTCOME MEASURES

The primary outcome was the quality of the surgical conditions evaluated with the Leiden-Surgical Rating Scale (L-SRS) by a blinded surgeon. Secondary outcomes included tracheal intubating conditions and adverse events.

RESULTS

The percentage of L-SRS scores of 4 or 5 was similar among the three groups at all the assessment times ( P  > 0.05 for each time interval). The distribution of L-SRS scores was also similar among the three groups. There were no significant differences in operating condition scores between the groups at any time interval ( P  > 0.05 for each time interval). The incidence of adverse events during anaesthesia induction was significantly higher in the no NMB group (51.4%) than in the other two groups (13.6% and 14.7%) (adjusted P  = 0.012 and adjusted P  = 0.003). In particular, clinically unacceptable intubation conditions occurred in 12 patients (34.3%) in the no NMB group, significantly more than in the shallow NMB group (6.1%, adjusted P  = 0.012) and moderate NMB group (2.9%, adjusted P  = 0.003). There was no statistically significant difference in the incidence of adverse events in the PACU among the three groups ( P  = 0.103).

CONCLUSIONS

The depth of NMB was not associated with superior surgical conditions during laparoscopic surgery, but it was associated with a reduction in adverse events during induction and maintenance of anaesthesia in neonates and small infants.

TRIAL REGISTRATION

Registered at www.chictr.org.cn (ChiCTR2100052296).

Hand or foot train-of-four tests and surgical site muscle relaxation assessed with multiple motor evoked potentials: A prospective observational study

BACKGROUND

Intra-operative muscle relaxation is often required in orthopaedic surgery and the hand train-of-four (TOF) test is usually used for its quantification. However, even though full muscle relaxation is claimed by anaesthesiologists based on a TOF count of zero, surgeons observe residual muscle activity.

OBJECTIVE

The aim of the study was to assess if hand or foot TOF adequately represents intra-operative muscle relaxation compared with multiple motor evoked potentials.

DESIGN

Prospective observational study.

SETTING

A single-centre study performed between February 2016 and December 2018 at the Balgrist University Hospital, Zurich, Switzerland.

PATIENTS

Twenty patients scheduled for elective lumbar spinal fusion were prospectively enrolled in this study after giving written informed consent.

INTERVENTIONS

To assess neuromuscular blockade (NMB) with the intermediate duration nondepolarising neuromuscular blocking agent rocuronium, hand TOF (adductor pollicis) and foot TOF (flexor hallucis brevis) monitoring, and muscle motor evoked potentials (MMEPs) from the upper and lower extremities were assessed prior to surgery under general anaesthesia. Following baseline measurements, muscle relaxation was performed with rocuronium until the spinal surgeon observed sufficient relaxation for surgical intervention. At this timepoint, NMB was assessed by TOF and MMEP.

MAIN OUTCOME MEASURES

The primary outcome was to determine the different effect of rocuronium on muscle relaxation comparing hand and foot TOF with the paraspinal musculature assessed by MMEP.

RESULTS

Hand TOF was more resistant to NMB and had a shorter recovery time than foot TOF. When comparing MMEPs, muscle relaxation occurred first in the hip abductors, and the paraspinal and deltoid muscles. The most resistant muscle to NMB was the abductor digiti minimi. Direct comparison showed that repetitive MMEPs simultaneously recorded from various muscles at the upper and lower extremities and from paraspinal muscles reflect muscle relaxation similar to TOF testing.

CONCLUSION

Hand TOF is superior to foot TOF in assessing muscle relaxation during spinal surgery. Hand TOF adequately represents the degree of muscle relaxation not only for the paraspinal muscles but also for all orthopaedic surgical sites where NMB is crucial for good surgical conditions.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03318718).

Deep neuromuscular block does not improve surgical conditions in patients receiving sevoflurane anaesthesia for laparoscopic renal surgery

Background

Deep neuromuscular block is associated with improved working conditions during laparoscopic surgery when propofol is used as a general anaesthetic. However, whether deep neuromuscular block yields similar beneficial effects when anaesthesia is maintained using volatile inhalation anaesthesia has not been systematically investigated. Volatile anaesthetics, as opposed to intravenous agents, potentiate muscle relaxation, which potentially reduces the need for deep neuromuscular block to obtain optimal surgical conditions. We examined whether deep neuromuscular block improves surgical conditions over moderate neuromuscular block during sevoflurane anaesthesia.

Methods

In this single-centre, prospective, randomised, double-blind study, 98 patients scheduled for elective renal surgery were randomised to receive deep (post-tetanic count 1–2 twitches) or a moderate neuromuscular block (train-of-four 1–2 twitches). Anaesthesia was maintained with sevoflurane and titrated to bispectral index values between 40 and 50. Pneumoperitoneum pressure was maintained at 12 mm Hg. The primary outcome was the difference in surgical conditions, scored at 15 min intervals by one of eight blinded surgeons using a 5-point Leiden-Surgical Rating Scale (L-SRS) that scores the quality of the surgical field from extremely poor¹ to optimal⁵.

Results

Deep neuromuscular block did not improve surgical conditions compared with moderate neuromuscular block: mean (standard deviation) L-SRS 4.8 (0.3) vs 4.8 (0.4), respectively (P=0.94). Secondary outcomes, including unplanned postoperative readmissions and prolonged hospital admission, were not significantly different.

Conclusions

During sevoflurane anaesthesia, deep neuromuscular block did not improve surgical conditions over moderate neuromuscular block in normal-pressure laparoscopic renal surgery.

Clinical trial registration

NL7844 (www.trialregister.nl).