Risk of airway fire with the use of KTP laser and high flow humidified oxygen delivery in a laryngeal surgery model

Airway surgery presents a unique environment for operating room fire to occur. This study aims to explore the factors of combustion when using KTP laser with high flow oxygen in an ex-vivo model. The variables tested were varying tissue type, tissue condition, oxygen concentration, laser setting, and smoke evacuation in a stainless-steel model. Outcome measures were time of lasing to the first spark and/or flame. A multivariate Cox proportional hazard model was used to determine the risk of spark and flame across the different risk factors. For every 10% increase in oxygen concentration above 60% the risk of flame increased by a factor of 2.3. Continuous laser setting at 2.6 W increased the risk by a factor of 72.8. The risk of lasing adipose tissue is 7.3 times higher than that of muscle. Charred tissue increases the risk of flame by a factor of 92.8. Flame occurred without a preceding spark 93.6% of the time. Using KTP laser in the pulsed mode with low wattages, minimising lasing time, reducing the oxygen concentration and avoiding lasing adipose or charred tissue produce a relatively low estimated risk of spark or flame.

Clinical Applications of Office-Based Laryngeal Surgery With KTP Laser

The pulsed photoangiolytic 532-nm potassium-titanyl-phosphate (KTP) laser has emerged in recent years as an efficacious treatment modality for vocal fold lesions. It also has broadened the indications for other laryngeal laser surgery. Features of KTP laser that it is a fiber-based delivery system and its energy is selectively absorbed by oxyhemoglobin make it suitable for office-based laryngeal procedures. An office-based KTP laser surgery provides an alternative management option for benign laryngeal diseases and can be performed comfortably under flexible endoscopic guidance which is placed through the nose of a fully awake patient. Office-based laryngeal surgery with a KTP laser can alleviate the need for general anesthesia. However, there are some limitations to apply due to reduced visual precision and the fact that the vocal folds are moving during procedures. Clinicians should carefully weigh the advantages and disadvantages of office-based procedures before a treatment option is selected. Patient selection and standardized laser energy parameters may help in decreasing complications and improving the treatment results.

High-Definition 3-D Exoscope for Micro-Laryngeal Surgery: A Preliminary Clinical Experience in 41 Patients

Objective: The aim of this prospective clinical study is to evaluate the feasibility of the micro-laryngeal surgery (MLS) using a 3D operating exoscope (OE) in substitution to a conventional operating microscope (OM). Methods: A total of 41 consecutive patients were included (male: 26; median age: 55.0 years; IQR: 46.0-68.0). After each procedure, the surgeon and the scrub nurse were asked to fill out a tailored questionnaire on a 3-point Likert scale (1—not acceptable, 2—acceptable, 3—good) including 12 items. Results: The majority of the procedures were therapeutic (n = 31, 75.6%), while the remaining were diagnostic (n = 10, 24.4%). All surgeries were successfully completed without the support of the OM, and no complications or unwanted delays were detected. The majority of the individual items were judged “good” either by surgeons (n = 399, 81.1%) and scrub nurses (n = 287, 87.5%). The natural posture during the procedure, and the ease of use the joystick and focusing were the best-rated items by the surgeons. Conclusions: This study demonstrates the feasibility of MLS using the OE. Further comparative clinical studies are needed to clarify its real value in substitution to a conventional operating microscope and to better define advantages and disadvantages.