TISSUE EFFECTS FROM LASER-INDUCED ENDOTRACHEAL TUBE FIRES.
A study was undertaken to examine the injury from laser ignited endotracheal tubes in the canine larynx, distal bronchi and lungs. Three endotracheal tubes were tested; the Rusch red rubber, the PVC polyvinylchloride and silicone. Two types of endotracheal tube fires were studied - those produced by extraluminal and those produced by intraluminal ignition. The red rubber and silastic endotracheal tube ignited when CO//2 laser energy was directed at their external surfaces, provided a sufficient O//2 concentration was present in the area of laser impact. The laryngeal injury produced by this type of fire is that of a second degree burn. No lung or bronchial injuries were evident with this type of fire. When the laser beam produced a fire in the PVC tube lumen, the resulting lung and bronchial injuries were severe. The use of this tube is not recommended during laser endoscopic surgery.
