Effect of intraoral glossopharyngeal nerve block on hemodynamic response to mouth retractor placement in transoral robotic surgery: a randomized clinical trial.
Ankita Bhasin, Venkata Ganesh, Ajay Singh et al.
✦ AI-curated · Sources linked
In 30 seconds
This prospective, single-centre randomized clinical trial assessed whether bilateral intraoral glossopharyngeal nerve block attenuates the blood-pressure response to mouth retractor placement during transoral robotic surgery. Among 42 adults with ASA I–II status, a >20% increase in mean arterial pressure within 10 minutes occurred in 3 of 21 patients (14.3%) receiving the block versus 8 of 21 (38.1%) controls. The posterior mean absolute risk difference was -23.9% (95% credible interval [CrI]: -49.4% to 2.2%), with a 0.964 posterior probability of benefit, above the prespecified threshold. The authors note substantial uncertainty in the effect magnitude.
Key findings
- A >20% MAP increase occurred in 14.3% with block versus 38.1% in controls.
- The posterior mean absolute risk difference was -23.9% (95% CrI: -49.4% to 2.2%); P (ARD < 0) = 0.964.
- Maximum MAP and heart rate were lower in the block group, with posterior probabilities of a difference below zero of 0.998 and 0.995, respectively.
- Bispectral index values were comparable between groups throughout the procedure.
Why it matters
Rigid retractor placement can provoke a sympathetic response, which may be consequential for patients vulnerable to hemodynamic stress. This trial provides randomized evidence that targeting sensory innervation with a glossopharyngeal nerve block may reduce that response during TORS. However, the wide credible interval leaves the size of any benefit uncertain, and the study did not establish effects on clinical outcomes.
What to keep in mind
The single-centre trial included 42 patients with ASA I–II status. The credible interval was wide; the anaesthesiologist was not blinded, and no sham procedure was used. Clinical endpoints were not assessed.