PHILADELPHIA -- A deeper neuromuscular block (NMB) facilitated laparoscopic surgery without having an effect on intraoperative safety and postoperative outcomes, according to a multicenter randomized trial.
For patients undergoing a complex elective laparoscopic abdominal surgery in European centers, the incidence of adverse events (AEs) did not differ significantly between those randomized to deep NMB (post-tetanic count 1-2 twitches) or those assigned standard NMB (single shot NMB agent at induction only):
- Any intraoperative AEs: 14.9% vs 18.3%, respectively
- Anesthesia-related AEs: 7.7% vs 11.6%
- Surgical-related AEs: 7.7% vs 8.0%
Thirty-day postoperative complication and readmission rates were about the same between groups. Also comparable were their self-reported quality of recovery and quality-of-life scores, reported Merel Snoek, MD, of Leiden University Medical Center in the Netherlands.
However, working in favor of deep NMB was the secondary outcome of unfavorable surgical working conditions -- namely a limited laparoscopic working field or the presence of disruptive muscle contractions or movements -- which was less likely with deep NMB than with standard NMB (1.6% vs 10.4%, P<0.0001).
Thus, deep NMB improved surgical satisfaction despite not reducing intraoperative AEs and not improving postoperative patient outcomes, Snoek reported at the American Society of Anesthesiologists (ASA) annual meeting.
This trial thus lends some support to the to prevent abdominal contractions for improved views during laparoscopic surgery.
While NMB is frequently used in practice, routine deep NMB has been due to the lack of strong evidence of real patient benefit and the associated expense of costly to reverse the block.
Snoek said that her group is probably not changing practice based on the present results, in response to a question by ASA session co-moderator Joseph Pena, MD, of Northwell Health in Manhasset, New York.
The double-blind trial had 731 people enrolled from February 2020 to November 2023 at several European centers.
All participants underwent laparoscopic abdominal surgery under general anesthesia with propofol, sevoflurane, or desflurane targeting a hypnotic depth of BIS 50. Study procedures had a end-tidal pCO2 of 4.5-5.5 kPa (34-42 mmHg) and standard insufflation pressures targeted 12 mmHg, according to Snoek.
She said her group had characterized AEs based on ClassIntra scale, counting events ranging in severity from the patient needing additional minor treatment or intervention for moderate symptoms (grade II) to death (grade V).
A blinded team scored AEs at the end of every surgery, and a blinded adjudication committee reviewed them regularly.
AEs arose in 16.2% of cases. Hypotension with norepinephrine constituted the most frequent AE (31%). The incidence of inadequate anesthesia occurred in no patient under deep NMB, compared with 15 in the controls.
Surgical satisfaction was rated according to the (5-point scale ranging extremely poor conditions to optimal conditions).
Postoperative outcomes at 30 days were based on the Clavien-Dindo classification (38.4% with deep NMB vs 39.3% with standard NMB, P=0.855) and Comprehensive Complication Index (median 20.9 vs 15.0, P=0.693).
Disclosures
The trial was supported by Merck.
Snoek disclosed no relationships with industry.
Primary Source
American Society of Anesthesiologists
Snoek M, et al "The impact of deep versus standard neuromuscular blockade on intra-operative safety during laparoscopic surgery: an international multicenter randomized controlled double-blind strategy trial" ASA 2024.