Assessment of Truflex™ articulating stylet versus conventional rigid Portex™ stylet as an intubation guide with the D-blade of C-Mac™ videolaryngoscope during elective tracheal intubation: study protocol for a randomized controlled trial

BACKGROUND A variety of videolaryngoscopes with angulated blade have been recently introduced into clinical practice. They provide an indirect view of the glottic structures in normal and challenging clinical settings. Despite the very good visualization of the laryngeal structures by these devices, the insertion and advancement of the endotracheal tube may be prolonged and occasionally fail as it does not conform to the enhanced angulation of the blade. To overcome this handicap, it is recommended to use a pre-shaped, styleted tracheal tube during intubation. Unfortunately, these malleable rigid stylets permit only a fixed shape to the advancing endotracheal tube. This may necessitate withdrawal of endotracheal tube-stylet assembly for reshaping, before undertaking a new attempt. This may cause soft tissue injury and hemodynamic disturbance.This single-blinded randomized clinical trial aims to overcome these handicaps using a novel method of dynamically changing the shape of the advancing endotracheal tube by Truflex articulating stylet as per need during D-blade C-Mac videolaryngoscopy. METHODS One hundred and fifty four patients between 18 and 60 years of age belonging to either sex undergoing tracheal intubation under uniform general anesthetic technique will be randomly divided into Portex malleable stylet group and Truflex articulating stylet group. The primary efficacy variable of success/failure between the two groups will be analyzed using the chi square test. For comparison of intubation times and the Intubation Difficulty Score, ANOVA will be used. Primary efficacy endpoint results will be successful or failed tracheal intubation in the first attempt, total intubation time and the intubation difficulty score. Secondary efficacy endpoints will be overall user satisfaction graded from 1 to 10 (1 = very poor, 10 = excellent), Cormack and Lehane's grading, glotticoscopy time and ETT negotiation time and total number of intubation attempts. Result of safety endpoints will include dental and airway trauma, hemodynamic disturbances, arrhythmias or cardiac arrest. TRIAL REGISTRATION Current Controlled Trials ISRCTN57679531; Date of registration 12/02/2013.