KTP LASER-RESISTANT PROPERTIES OF THE REINFORCED LARYNGEAL MASK AIRWAY

We have assessed, in vitro, the effect of KTP laser strike on the rein forced laryngeal mask airway (RLMA) under a variety of conditions. At power densities normally encountered in clinical practice, using a div ergent KTP laser beam, the RLMA could not be penetrated and did not ig nite with laser strike. The RLMA was penetrated at a high power densit y of 6.94 W mm(-2) after 45-60 s. A flame appeared over the RLMA shaft at this power density after 12-35 s. The black marker line on the RLM A shaft was somewhat more vulnerable to the effects of laser strike. T he flow of oxygen and nitrous oxide within the shaft did not appreciab ly alter the laser-resistant properties of the RLMA. The RLMA cuff was more vulnerable to laser strike than was the shaft and was penetrated at very low power densities. Filling the cuff with saline had a prote ctive effect and penetration did not occur at power densities which ca used penetration of air-filled cuffs (0.37 W mm(-2)).