The pressure exerted on the tongue during intubation with simultaneous cervical spine immobilisation: a comparison between four videolaryngoscopes and the Macintosh laryngoscope—a manikin study

Abstract

Excessive pressures exerted on the tongue during intubation may be associated with serious complications and may make intubation more difficult. The aim of this study was to evaluate five different intubating devices in the hands of experienced anaesthetists during simulated conditions of reduced cervical spine mobility. Forty senior anaesthetists participated in the study (female = 18, male = 22). The mean pressure exerted on the tongue during intubation was recorded with a standard manometer. The overall intubation success rate as well as the difference in exerted pressures between female and male anaesthetists were also assessed. The five studied devices were used by each participant and they were randomly chosen. Each anaesthetists participating in the study had over 15 years of clinical anaesthetic practice. The mean pressure exerted on the tongue during intubation was significantly lower when the videolaryngoscopes (VLs) were used (p < 0.0001 for each of the studied VL). There were failed intubation attempts with all of the studied devices, the highest failure rate was in the Airtraq® group, 10 in 40 (25%). Female anaesthetists exerted lower pressures during intubation with all studied devices (except the Airtraq®). However, the difference was only significant for the Macintosh laryngoscope (p = 0.0083). The blades of VLs exerted lower pressures on the tongue during intubation than the Macintosh laryngoscope blade. Their use may be associated with less complications. Furthermore, male anaesthetists exerted higher pressures on the soft tissues although this was neither statistically nor clinically significant. There was higher failed intubation rate in the male anaesthetist group.

Video-assisted versus macintosh direct laryngoscopy for intubation of obese patients: a meta-analysis of randomized controlled trials

“…Most anesthesiologists are more familiar with direct laryngoscopy, but we couldn't analyze the level of experience in our review, as the level of experience with video-laryngoscopes or advanced airway technology has not been consistently reported. While previous studies have demonstrated a lower force applied on the teeth [35], the tongue [36], and the glottis [37] in patients undergoing video-laryngoscopy compared to direct laryngoscopy, this is, to our knowledge, the first study to systematically evaluate the incidence of intubation related injury in Video-assisted compared to direct laryngoscopy. The data obtained from the analysis of studies may suggest the superiority of particular methods of management; however, the clinical decision concerning the use of particular types of laryngoscopes must depend on the practice and protocols of a given institution as well as individual experience in the use of a given device and anatomical conditions of a specific patient.…”

Ergonomic Challenges Inherent in Neonatal Resuscitation

“…For example, the degree of force that can be safely applied to the soft tissues such as the tongue and posterior oropharynx and the degree of torque used to manipulate the airway in order to expose the trachea with the laryngoscope are essentially unknown. While a number of investigators have begun to study these factors in simulated and real adult patients [19,20,21,22,23,24,25,26,27,28,29], this data cannot be directly translated to neonatal patients due to different equipment used and the large differences in patient weight and size. Furthermore, the immature and more delicate tissues of newborns are at greater risk of trauma, and their anterior tracheal anatomy can make intubation more challenging than in older patients.…”