A comment on oral vs. nasal intubation and post-extubation laryngeal injury

To the editor,

I read with great interest the report by Meena & Gill [1], which prospectively and commendably under clinician blind- ing assessed early laryngoscopic findings after extubation. The pragmatic design and timely endoscopic verification make a useful contribution to the perioperative airway litera- ture. However, two clarifications would strengthen reproduc- ibility and align the conclusions with the study’s design.

The analysis records “intubation duration,” which appears to reflect time to achieve intubation rather than the total time patients remained intubated during surgery the latter being the physiologically relevant dose for pressure and friction- mediated injury. Crucially, cuff pressure (and its time course) was not measured. Because both total intubation time and cuff pressure-time exposure are primary determinants of mucosal ischemia and contact trauma, their omission likely induces nondifferential exposure misclassification, biasing route comparisons toward no difference. Even if the two routes truly differ under longer anesthesia or higher cuff pres- sures, the current specification would dilute that signal. Mini- mal remediation is possible by reporting anesthesia/airway time from records, stratifying by case length, and conducting sensitivity analyses that model plausible cuff-pressure ranges.

Airway route was chosen by surgical indication and anes- thesiologist preference a classic confounding by indication setting. With a modest sample and few moderate-to-severe events, a standard multivariable model cannot reliably con- trol imbalances in case mix (operative field, positioning, instrumentation such as Magill forceps, operator effects In this context, a non-significant p-value is not evidence of equivalence; it only indicates insufficient power to detect a difference. An appropriate inference framework would pre- specify a clinically meaningful non-inferiority margin (e.g., absolute risk difference ≤ 10%), estimate effect sizes with 95% CIs, and use balancing methods (propensity scores/ IPTW) to address allocation bias. Absent these elements, concluding that routes “demonstrated comparable rates and severity” overstates what the design can support.