PROSPECTIVE RANDOMIZED CROSSOVER COMPARATIVE STUDY OF DIRECT LARYNGOSCOPIC VIEW IN SNIFFING AND 25 DEGREES BACKUP POSITION

Withthis study we want to evaluate whether laryngoscopic view is better in 25degrees back up position as compared to sniffing position?  B. J. Lee et al in2007 have shown that during laryngoscopy, the laryngeal view, as assessed byPercentage of glottis opening (POGO) scores, improves significantly in the 25degrees back-up position when compared with the flat supine position.However 25 degrees back-up position has not been compared with the sniffingposition which is standard of care for direct laryngoscopy. The aim ofthis study is to evaluate the effect of 25 degree back up position on laryngealview compared with the sniffing position during direct laryngoscopy. Theprimary objective is to compare the laryngeal view in both positions by bymodified Cormack – Lehane grading.  Secondary Objectives are to compare thelaryngeal view in both positions after applying external laryngeal  pressure if necessary, to compare thedifficulty in intubation with the help of Intubation Difficulty Scale(IDS)and to find out the mode value ofpillow height required to achieve optimal sniffing ( external auditory meatusto sternal notch ) position. 100 adult patients ASA I, II and III physicalstatus posted for surgery under general anaesthesia with endotrachealintubation will be studied. A detailed preanaesthetic evaluation of airway willbe performed which includes BMI, thyromental distance, interincisor gap andmodified Mallampatti grading, and adequacy of neck movement.Patients will be randomized as Group S where intubation will be done insniffing position and Group B where intubation will be done in 25 degreesbackup position. Laryngoscopy will be performed in both positions in eachpatient followed by endotracheal intubation. Glottic visualization will beassessed by modified Cormack Lehane classification. IntubationDifficulty Scale (IDS) will assess the intubation difficulty.