The intubating laryngeal mask airway facilitates tracheal intubation in the lateral position

Although the difficulty of tracheal intubation in the lateral position has not been systematically evaluated, airway loss during surgery in a laterally positioned patient may have hazardous consequences. We explored whether the intubating laryngeal mask airway (ILMA) facilitates tracheal intubation in patients with normal airway anatomy, i.e., Mallampati grade less than or equal to3 and thyromental distance greater than or equal to5 cm, positioned in the lateral position. We evaluated whether this technique can be used as a rescue when the airway is lost during the middle of surgery in laterally positioned patients with respect to success rate and intubation time. Anesthesia was induced with propofol, fentanyl, and vecuronium in 50 patients undergoing spine surgery for lumbar disk herniation (Lateral) and 50 undergoing other surgical procedures (Supine). Patients having disk surgery (Lateral) were positioned on their right or left sides before induction of general anesthesia, and intubation was performed in dthat position. Patients in the control group (Supine) were anesthetized in supine position, and intubation was performed in that position. Intubation was performed blindly via an ILMA in both groups. The time required for intubation and number and types of adjusting maneuvers used were recorded. Data were compared by the Mann-Whitney U test, Fisher's exact test, chi(2) test, or unpaired Student's t-test, as appropriate. Data presented as mean (SD). Demographic and airway measures were similar in the two groups, except for mouth opening, which was slightly wider in patients in the lateral position: 5.1 (0.9) versus 4.6 (0.7) cm. The time required for intubation was similar in each group (approximate to25 s), as was intubation success (96%). We conclude that blind intubation via an ILMA offers a frequent success rate and a clinically acceptable intubation time (<1 min) even in the lateral position.