Time-to-intubation in obese patients. A randomized study comparing direct laryngoscopy and videolaryngoscopy in experienced anesthetists.

Background: Airway management may be difficult in obese patients. Moreover, during prolonged intubation, oxygen desaturation develops rapidly. Videolaryngoscopy improves the view of the larynx, and the Storz® C-MAC™ has been shown to be superior to other videolaryngoscopes in terms of intubation time in obese patients. However, no effort has been made to compare the Storz® C-MAC™ with direct laryngoscopy. The aim of the study was to evaluate if the use of Storz® C-MAC™ may reduce intubation time when compared to direct laryngoscopy (classic Macintosh® blade).

Methods: Eighty patients with Body Mass Index >35 kg/m2 were randomized to orotracheal intubation using either Macintosh® laryngoscope, or the Storz® C-MAC™ with the standard Macintosh blade. Patients had no previous history of a difficult airway. Time-to-intubation (TTI) was defined as the time from the moment anesthetist took the laryngoscope until end-tidal carbon dioxide was detected.

Results: No significant difference in TTI could be demonstrated between the two devices tested (mean difference -1.7 s (95% CI:-6.9 to 3.5 s). All patients in the videolaryngoscopy group were successfully intubated with the allocated device, whereas five patients in the direct laryngoscopy group required an alternative device for successful intubation. No significant difference regarding the subjective difficulty of intubation and postoperative sore throat between groups was demonstrated.

Conclusions: In obese patients the airway may be secured equally fast using direct laryngoscopy (Macintosh®) and with videolaryngoscopy using the Stortz® C-MAC™. The risk for failed intubation, however, appears to be greater with direct laryngoscopy, especially in male obese patients.