Does the TruBlue Laser Set Microlaryngoscopy Equipment on Fire? A Systematic Evaluation

INTRODUCTION

The risk of fire during laser microlaryngoscopy is well known. However, limited information is available about fire risk with the novel TruBlue laser. This study systematically evaluates its interactions with common surgical supplies, offering valuable insights into safety considerations for surgeons.

MATERIAL AND METHODS

We used experimental conditions to test the extent to which TruBlue laser energy produces smoke, perforation, or fire in Rüsch®, Medtronic™ and microlaryngeal endotracheal tubes and in surgical pledgets.

RESULTS

Only the Microlaryngeal Tube (MLT) caught fire. Notably, it happened only when the laser fiber shifted on the tube's surface. Smoke emerged solely from the laser fiber applied to the Medtronic™ shaft and only during continuous contact mode. Cuff perforation and smoke emanating from the shaft occurred in three-quarters of the Rüsch® trials. The pledgets' radiopaque segment exhibited a greater combustibility than other segments (p < 0.01). In many of the pledget trials, faster smoke emission occurred with shorter laser-to-target distances (p < 0.05). Water-soaked pledgets displayed a reduced rate of smoke production (p < 0.01) and string division.

CONCLUSION

The Medtronic™ tube assures remarkable safety with a nonignitable shaft and low cuff ignition. The MLT poses the highest ignition risk. Cuff perforation risk is mitigated by maintaining a 0.3-cm distance from the laser fiber tip. Pledget fire risk is mitigated by positioning the radiopaque part away from the laser beam and by soaking the pledget with water. Laser division of the pledgets' string was common.

LEVEL OF EVIDENCE

NA Laryngoscope, 135:1752-1758, 2025.

Surgical fires in laser laryngeal surgery: are we safe enough?

OBJECTIVE

Laser surgery of the larynx and airway remains high risk for the formation of operating room fire. Traditional methods of fire prevention have included use of "laser safe" tubes, inflation of a protective cuff with saline, and wet pledgets to protect the endotracheal tube from laser strikes. We tested a mechanical model of laser laryngeal surgery to evaluate the fire risk.

STUDY DESIGN

Mechanical model.

SETTING

Laboratory.

SUBJECTS AND METHODS

An intubation mannequin was positioned for suspension microlaryngoscopy. A Laser-Shield II cuffed endotracheal tube was placed through the larynx and the cuff inflated using saline. Wet pledgets covered the inflated cuff. A CO2 laser created an inadvertent cuff strike at varying oxygen concentrations. Risk reduction measures were implemented to discern any notable change in the outcome after fire.

RESULTS

At 100% FiO2 an immediate fire with sustained flame was created and at 40% FiO2 a near immediate sustained flame was created. At 29% FiO2, a small nonsustained flame was noted. At room air, no fire was created. There was no discernible difference in the severity of laryngeal damage after the fire occurred whether the tube was immediately pulled from the mannequin or if saline was poured down the airway as a first response.

CONCLUSIONS

While "laser safe" tubes provide a layer of protection against fires, they are not fire proof. Inadvertent cuff perforation may result in fire formation in low-level oxygen enriched environments. Placement of wet pledgets do not provide absolute protection. Endotracheal tube (ETT) cuffs should be placed distally well away from an inadvertent laser strike while maintaining the minimum supplemental oxygen necessary.