Laser safety in otolaryngology--head and neck surgery: anesthetic and educational considerations for laryngeal surgery.

Two investigations concerning anesthetic and educational considerations for laser safety in microlaryngeal carbon dioxide laser surgery have been performed. The first study demonstrated that attendance at a "hands-on" laser surgery course that stressed safety precautions was associated with a reduced rate of laser-related complications in the selected group of otolaryngologists who participated in the course, when compared to another selected group of otolaryngologists who were members of a senior otolaryngology society, and surveyed solely on the basis of their society membership. The second series of studies compared the incendiary characteristics of three endotracheal tubes in various mixtures of oxygen, diluted with either helium or nitrogen. It was determined that the polyvinyl chloride tube should not be used for laser surgery, even when wrapped with reflective, metallic tape. The safest anesthetic gas mixture was found to be 30% oxygen in helium; the addition of 2% halothane did not have an adverse effect, as had been previously reported. Both the Xomed Laser-Shield and Rusch red rubber endotracheal tubes were found to be safe, when used with the laser in the pulsed mode in an atmosphere of 100% oxygen. When the laser was used in the continuous mode, both tubes ignited in an atmosphere of 30% oxygen in helium. These findings challenged the previously reported levels of safety associated with the use of an unwrapped Xomed tube. Based on the results of this investigation, it has been concluded that both the Rusch red rubber tube and the Xomed Laser-Shield tube should be wrapped with reflective, metallic tape, when used for cases of microlaryngeal surgery with the carbon dioxide laser.