Comparison of the rate of successful endotracheal intubation between the "sniffing" and "ramped" positions in patients with an expected difficult intubation: a prospective randomized study

Abstract

BackgroundOptimal head and neck positioning and clinical experience are important factors for successful endotracheal intubation in patients with a difficult airway. This study aimed to investigate the rate of successful endotracheal intubation between the sniffing and ramped positions in patients with an expected difficult intubation.MethodsThe study included 204 patients with an expected difficult intubation (airway difficulty score ≥ 8) based on the preoperative airway assessment. The patients were randomized into the following groups: group S was placed in the sniffing position, and group R was placed in the ramped position during direct laryngoscopy. The primary outcome was successful endotracheal intubation and the secondary measure was laryngeal view in the ramped or sniffing position when the operating table was placed at two different heights.ResultsGroup R showed a higher rate of successful endotracheal intubation and better laryngeal view than group S (P < 0.05). The rate of successful endotracheal intubation was higher in group R than in group S at both heights of the operating table; but, it was not different within each group. Laryngeal view was not different between the two groups and within each group when the two heights of the operating table were used. Fully trained and experienced attending anesthesiologists achieved a higher rate of successful endotracheal intubation than less experienced residents in group R (P < 0.05) but not in group S.ConclusionsRamped position and clinical experience can be important factors for laryngeal view and success rate of endotracheal intubation in patients with an expected difficult intubation.

Video Laryngoscopy Compared to Augmented Direct Laryngoscopy in Adult Emergency Department Tracheal Intubations: A National Emergency Airway Registry (NEAR) Study

“…One randomized controlled trial of ramped versus sniffing head position during urgent intubations in the ICU found that ramping worsened the Cormack-Lehane grade view of the airway, while a similar study in an operating room population showed significantly better laryngeal views when patients were ramped. 20,21 Despite these mixed data, more than one-quarter of all patients in our study were placed in a ramped position. This parallels the percentage of patients listed as being either obese or morbidly obese.…”

A randomised comparative study on customised versus fixed sized pillow for tracheal intubation in the sniffing position by Macintosh laryngoscopy

“…This is also the aim in 'ramping' which has an established role in obese patients. [ 8 9 ] This practice is however not routine for non-obese patients. The aim of the present study was to compare a fixed height obtained by routinely used ring versus a customised height by addition of sheets (for horizontal alignment of EAM and sternum) to achieve head elevation for tracheal intubation in terms of glottis visualisation and time taken for intubation.…”

Modified-ramped position: a New Position for Intubation of Obese Females. A Randomized Controlled Pilot Study

“…Since then, the studies which compared the ramped position and the sniffing position showed relatively conflicting results. Ramped position was proved superior to sniffing position in both obese, non-obese populations [11]; and in patients with expected difficult intubation [12]. Semler et al had, surprisingly, reported different results which favored the sniffing position over the ramped position in 260 critically ill patients [6].…”