Comparison Study in Adult Surgical Patients of 5 Airway Devices

Overview

The placement of endotracheal tubes (intubation) is a physiologically stressful procedure for patients. Laryngoscopes are devices-typically composed of a blade attached to a handle with a light source-that allow examination of the upper airway through the mouth, often for the purposes of intubation. Recently some new laryngoscope devices (including the Airtraq® Optical Laryngoscope, the Storz DCI Video laryngoscope®, McGRATH® Video Laryngoscope, and the GlideScope®) have been developed, which may either decrease the stress related to intubation (reduce neck extension, reduce risk of complications or reduce time elapsed during intubation) or improve intubation success (reduce the number of attempts at intubating). Data are being collected in this study to determine which of these commonly-used devices may be better, particularly in comparison to the current hospital standard, the Macintosh laryngoscope. All of the devices to be used in this study are currently cleared or exempt by the Food and Drug Administration (FDA).

Historically, optical and video laryngoscopes have been used as alternative airway management devices for the difficult airway, and as rescue devices. Their use by experienced laryngoscopists has not been compared in a prospective, randomized, head-to-head comparison for routine airway management in adult surgical patients. Video and optical laryngoscopes have been developed to improve the laryngeal view for tracheal intubation and to decrease physiological stress associated with the procedure. The objective of this study is to determine whether these devices offer superior intubating conditions for routine surgical management, over the Macintosh laryngoscope, which is the current standard. The devices to be compared in this study are the most commonly used video and optical laryngoscopes on the market and are cleared or exempt by the Food and Drug Administration (FDA). Eligible subjects include elective adult surgical patients with an ASA status between 1 and 3 requiring general endotracheal anesthesia. Subjects with a BMI ≥ 40, or undergoing surgery in close proximity to the neck will be excluded. Prior to surgery, subjects will receive a pre-anesthesia evaluation with particular attention to the airway using the Mallampati classification system; atlanto-occipital joint extension; thyro-mental distance; temporomandibular joint function; inter-incisor distance; and dental assessment. Subjects will be randomized for intubation with one of the five laryngoscopes in equal proportions. The following data were recorded: total intubation time, maximum neck extension using an angle gauge, glottic view, assessed by the anesthesiologist using the Cook modification of the Cormack-Lehane grading system (Figure 1), and ease of tracheal intubation using a 5-point rating scale; 5 (excellent) to 1 (poor). Subjects were queried about soreness or painful swallowing in the PACU and a week later via a phone call.