Anticipation of the difficult airway: preoperative airway assessment, an educational and quality improvement tool.

BACKGROUND: Assessment of the potentially difficult airway (DA) is a critical aspect of resident education. We investigated the impact of a new assessment form on airway prediction and management by anaesthesia residents. We hypothesized that residents would demonstrate improvement in evaluation of DAs over the study duration. METHODS: After IRB approval, anaesthesia residents were randomized into two groups: control (existing form) and experimental (new form). Data were collected prospectively from August 2008 to May 2010 on all non-obstetric adult patients undergoing non-emergent surgery. RESULTS: Eight thousand three hundred and sixty-four independent preoperative assessments were collected and 8075 were analysed. The experimental group had the higher completion rate than the control group (94.3% vs 84.3%, P=0.001). DA prediction was higher for the control group (71.2%) compared with the experimental group (69.1%; P=0.032). A significant improvement in prediction rates was found over time for the experimental group (likelihood estimate=0.00068, P=0.031). CONCLUSIONS: The use of a comprehensive airway assessment did not improve resident ability to predict a DA in an academic, tertiary-based hospital, anaesthesiology residency training programme.

Submental intubation: a literature review.

A literature review was performed to analyse the evidence supporting submental intubation and to aid in the development of a new airway algorithm in craniofacial surgery patients. A systematic search of Pub Med, OVID, the Cochrane Database and Google Scholar between January 1984 and April 2011 was performed. Measured variables included the outcome, complications, publishing specialty journal and method of intubation including technique modifications, indications for the procedure, devices utilized and the total procedure time to complete the submental intubation. Of the 842 patient cases from 41 articles represented in the review, the success rate was 100%. Minor complications were reported in 60 patients and included superficial skin infections (N=23), damage to the tube apparatus (N=10), fistula formation (N=10), right mainstem bronchus tube dislodgement/obstruction (N=5), hypertrophic scarring (N=3), accidental extubation in paediatric patients (N=2), excessive bronchial flexion (N=2), lingual nerve paresthesia (N=1), venous bleeding (N=2), mucocele (N=1), and dislodgement of the throat pack sticker in the submental wound (N=1). The average reported time to complete a submental intubation was 9.9 min. Submental intubation is a safe, effective and time efficient method for securing an airway when increased surgical exposure or restoration of occlusion is a priority.

A randomized clinical comparison of the Intersurgical i-gel and LMA Unique in non-obese adults during general surgery.

BACKGROUND: The i-gel is a cuffless, single-use supralaryngeal airway device designed to provide a more effective seal than the laryngeal mask airway (LMA). Although the superiority of the i-gel compared to the LMA Classic was determined in a previous study, no studies have been performed that compare it to the disposable LMA Unique. The aim of this study was to compare the Intersurgical i-gelTM against the LMA UniqueTM (uLMA) in terms of ease of placement, time of insertion, and adequacy of placement through a randomized, controlled clinical trial. METHODS: Following Institutional Review Board (IRB) approval and written informed consent, 50 adult patients were recruited for this study. All enrolled patients were ASA 1-2, Mallampati I-II, and scheduled to receive general anesthesia. Patients were randomized to have either the i-gel or the uLMA placed for airway management. After standardized induction techniques, the airway was secured with the assigned device. All patients were interviewed postoperatively for sore throat, hoarseness, and dysphagia. Standard vital signs, end-tidal CO2, tidal volumes, and peak pressures were recorded. Insertion time, leak pressures, and anatomic placement as assessed fiberoptically for the i-gel were recorded. Ease of placement and complications were also recorded. RESULTS: The insertion time was significantly less with the i-gel (21.04±12.6 s vs. 30.04±14.1 s, P=0.02). An inadequate seal was noted in three patients with the i-gel, and it was exchanged for the uLMA in all three cases. There were no significant differences in the ease of insertion, leak pressures, or fiberoptic view. Most of the fiberoptic views, as assessed through the drain tube, demonstrated esophageal mucosa (22/25). Patients receiving the i-gel were significantly more likely to require a second attempt at insertion by the anesthesiologist (OR 8.11, CI 1.1-58.6, P=0.03). Finally, patients receiving the size 5 i-gel were significantly more likely to complain of immediate postoperative symptoms, such as sore throat and dysphagia (OR 29.32, CI 1.4-613.1, P=0.03). CONCLUSION: Although the i-gel had a faster insertion time in comparison to the uLMA, there was a greater need for repeat insertions. The weight criteria established by the manufacturer may need to be readjusted to recommend a larger size device in some patients less than 90 kg because all of the repeat insertions were in patients weighing more than 80 kg. In all other aspects of its use, the i-gel performed similarly to the uLMA.

Seeing is believing: the importance of video laryngoscopy in teaching and in managing the difficult airway.

Of the several million patients who undergo surgery in North America annually, a large proportion undergo intubation of the trachea. In approximately 90% of these patients, the endotracheal tube is introduced using a traditional laryngoscope with a battery in the handle and a small bulb near the tip of the blade. This bulb provides a limited and often dim view of the glottic structures. In about 10% of cases, the patient is intubated using a flexible fiberoptic intubating scope. The authors have developed a video laryngoscope that preserves the standard blade configuration with a modified handle. A 3-mm image light guide is built into the blade, replacing the bulb. A small TV camera with an incorporated light bundle is inserted into the handle. A wide-angle panoramic view of the upper airway anatomy is displayed on a TV screen, which can be positioned at a convenient working distance. The use of a TV monitor is a well-accepted standard during minimally invasive surgical procedures.