Evaluation of laryngoscopic view, intubation difficulty and sympathetic response during direct laryngoscopy in sniffing position and simple head extension: a prospective and randomized comparative study

Background: Airway management is critical to the care of patients and direct laryngoscopy is the mainstay of airway management. Despite the proliferation of difficult airway devices, sniffing position for laryngoscopy remains the gold standard and ideal position. This prospective, randomized and single-blind study was done to evaluate and compare the laryngoscopic view, complexity of intubation and sympathetic response during laryngoscopy in sniffing position and simple head extension.Methods: One hundred and twenty patients, aged 20-50 years with American Society of Anesthesiologists (ASA) status 1 and 2 undergoing general anesthesia requiring orotracheal intubation were randomized into two groups. Group A used sniffing position and group B was put in simple head extension. Glottis visualization was assessed using Cormack and Lehane grade and ease of intubation was assessed on intubation difficulty scale. Laryngoscopic sympathetic response in two positions was also assessed.Results: Both the groups were comparable in demographic profiles. Glottic visualization and intubation difficulty score were better and statistically significant in sniffing position as compared to simple head extension. Although, sympathetic response was lower in sniffing position as compared to simple head extension, it was statistically insignificant.Conclusion: Sniffing position provided better glottis visualization and intubation difficulty score and increased the success rate of intubation as compared to simple head extension.