[Use of AirWay Scope for tracheal intubation in bright sunlight]

The AirWay Scope (AWS), which is equipped with a wide-angle LCD monitor, has been developed to achieve accurate and safe tracheal intubation under various conditions, including emergency settings. However, since bright sunlight degrades the image quality of LCDs, we investigated its usefulness outdoors in bright sunlight.

A single anesthesiologist intubated a mannequin with an AWS and conventional direct laryngoscope indoors and in sunlight outdoors, using 6 trials for each condition. Success rate, Cormack grade, and intubation time from device insertion to removal were recorded.

Indoors, all tracheal intubations with both devices achieved Cormack grade 1 and were successful. Outdoors, all the laryngoscopes achieved Cormack grade 1 and intubation was successful, whereas intubation with the AWS was successful in 3 trials, while 2 esophageal intubations and 1 failure also occurred. In addition, sunlight deteriorated the image quality of the LCD and Cormack grade could not be determined. The intubation times for the AWS and laryngoscope indoors were 8.7+/-1.8 and 17.0+/-6.5 sec, and outdoors were 18.7+/-9.0 and 21.3+/-4.9 sec, respectively.

Our findings indicate that successful tracheal intubation with an AWS is difficult to achieve in bright sunlight.