Incendiary characteristics of the laryngeal and re-inforced laryngeal mask airway

Susceptibility of the pilot balloon of the disposable laryngeal mask airway to puncture during laser therapy

The tube of the laryngeal mask airway is frequently protected by foil during ablative laser procedures. The pilot balloon, however, is often left exposed. The effect of firing seven different cutaneous lasers at the pilot balloon of a disposable laryngeal mask airway was examined to assess its susceptibility to accidental laser strikes. The time taken for each laser to penetrate the pilot balloon was calculated from an average of five laser strikes. The carbon dioxide and erbium YAG lasers punctured the pilot balloon in a mean (SD) of 0.07 (0.02) s and 0.7 (0.1) s, respectively, with the neodymium YAG laser the next quickest to puncture at 3.3 (1.0) s. All other lasers punctured the pilot balloon in less than 15 s. These data suggest that protection of the pilot balloon of the LMA is necessary when using carbon dioxide and erbium YAG lasers.

Anaesthesia for laser pharyngoplasty--a comparison of the tracheal tube with the reinforced laryngeal mask airway

A common cause of snoring is palatal flutter which occurs when turbulent air flow causes the flexible soft palate to flutter. Surgical correction involves either removal of the soft palate or a reduction in its flexibility. Laser pharyngoplasty is a new surgical procedure designed to stiffen the soft palate. It presents a unique combination of problems for the anaesthetist. In this paper we describe the evolution of the anaesthetic technique for laser pharyngoplasty and analyse the results of the first 165 cases. Points of particular interest include the use of the reinforced laryngeal mask airway compared with the tracheal tube and late onset pain.

The incendiary characteristics of the laryngeal and reinforced laryngeal mask airway to CO2 laser strike--a comparison with two polyvinyl chloride tracheal tubes

The incendiary characteristics of the laryngeal and reinforced laryngeal mask airway to the CO2 laser have been compared with two polyvinyl chloride tracheal tubes. Three different power densities (2.35, 4.7 and 9.8 x 10(3) watt/cm2) were used, with either oxygen or a 30% oxygen/70% nitrous oxide mixture flowing down the tube. The laryngeal mask airway (and reinforced model) was shown to be more resistant than the polyvinyl chloride tracheal tubes. The laryngeal mask tube could not be ignited at a power density of 2.25 x 10(3) watt/cm2 after five minutes, although penetration occurred in 20-30 seconds. A layer of silica ash built up at the impact site and protected the underlying tube. The laryngeal mask airway cuff was penetrated at 3 to 5 seconds. At this power density the polyvinyl chloride tube ignited in 2 to 8 seconds and the cuff was penetrated in 0.1 seconds. At the highest power density the tubes of all airways ignited within 0.2 seconds. The possibilities for improving the incendiary characteristics of the laryngeal mask airway are discussed.