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Maintenance of a patent airway and adequate ventilation during upper respiratory tract surgery can be difficult due to the need to maintain an unobstructed view of structures in the surgical field. This is usually achieved by placing smaller specialized (laser-resistant) endotracheal tubes and jet ventilation devices or utilizing intermittent or spontaneous ventilation techniques. This process is also complicated by using medical lasers that can cause a fire in an oxidizer-rich (oxygen, nitrous oxide) environment. Numerous recommendations exist, and comprehensive guidelines were created to minimize the risks inherent to these types of surgeries. This activity reviews the methods of ensuring adequate ventilation in a patient undergoing laser airway surgery, mechanisms of associated adverse events, and methods to prevent them and highlights the interprofessional team's roles in caring for patients undergoing laser airway surgery. Objectives: Review the risk factors common for laser surgeries of the airway. Describe the technique of maintaining a safe airway during the upper respiratory tract laser surgery. Identify the most common complications associated with laser surgery of the airway. Summarize some of the protective measures the interprofessional team can participate in when performing laser surgery of the airway. Access free multiple choice questions on this topic.

Medical lasers are used in procedures in various specialties, including otolaryngology, ophthalmology, dermatology, plastic surgery, and dental surgeries, as well as in intraabdominal, cardiothoracic, neurologic, gynecologic, and urologic procedures. Lasers provide a source of focused, coherent light capable of transmitting intense energy to a precise location. Each laser type acts upon a specific chromophore that preferentially absorbs the laser light resulting in heat and eventually in the destruction and cauterization of the tissue. Importantly, lasers can ignite flammable materials present in the operating field, such as endotracheal tubes, sponges, and catheters. Such foreign materials may themselves absorb the laser energy and ignite, or a spark can be created from the laser cauterization that then spreads to the combustible foreign material. Lasers also pose a risk of eye injury (both to the patient and operating room personnel), laser plume, electrical tripping, and release of chemical contaminants.

Medical lasers are used in procedures in various specialties, including otolaryngology, ophthalmology, dermatology, plastic surgery, and dental surgeries, as well as in intraabdominal, cardiothoracic, neurologic, gynecologic, and urologic procedures. Lasers provide a source of focused, coherent light capable of transmitting intense energy to a precise location. Each laser type acts upon a specific chromophore that preferentially absorbs the laser light resulting in heat and eventually in the destruction and cauterization of the tissue. Importantly, lasers can ignite flammable materials present in the operating field, such as endotracheal tubes, sponges, and catheters. Such foreign materials may themselves absorb the laser energy and ignite, or a spark can be created from the laser cauterization that then spreads to the combustible foreign material. Lasers also pose a risk of eye injury (both to the patient and operating room personnel), laser plume, electrical tripping, and release of chemical contaminants. Using a laser in upper aerodigestive surgery introduces a source of ignition that is especially dangerous when supplemental oxygen is added to the inspiratory gas mixture. This dilemma is constantly discussed, and multiple techniques have been developed to provide ventilation to an anesthetized patient while keeping the surgical field maximally accessible and minimizing laser-related hazards. The common ventilatory strategies include conventional endotracheal intubation, jet ventilation, intermittent apnea technique, and spontaneous breathing.[1] Multiple methods and numerous "laser-resistant" endotracheal tubes (ETT) were designed to protect the operating field from the hazards of medical lasers. The American Society of Anesthesiologists now recommends these as the default endotracheal airway during laser surgery of the respiratory tract.[2] The cuff is the most vulnerable part of the ETT. During intubation, once the tube passes through the vocal cords, the balloon at its distal end (cuff) is inflated with air (or saline) to occlude the trachea external to the tube and thus directs all the gas flows from the ETT exclusively to the trachea, and vice versa. A dye such as methylene blue is typically instilled into the cuff for such cases, so there is an obvious visual alert if the balloon is inadvertently popped. If the cuff is damaged by a laser (or other instruments or the patient's dentition), it becomes compromised and can no longer seal the trachea. This leads to a gas mixture rich in oxygen that can escape to the upper airway and surgical field. A fire may be ignited during this event or subsequent use of the laser. The ETT and other materials potentially present in the field, such as gauze and surgical drapes, are the most common fuels for an airway fire.[3]

The complications inherent to medical laser procedures are surgical fire, iatrogenic burns to surrounding tissues, and ocular injury.[22] Risk of fire: Following electrosurgical devices, surgical lasers are considered the second most common source of operating room fires.[23] Surgeries of the pharynx, larynx, and trachea are the most at-risk procedures, respectively. If an airway fire occurs: Remove the fuel source (immediately remove the ETT and other burning fragments). Remove the source of ignition (stop the laser). Eliminate the oxidizer flow (disconnect the circuit, and stop ventilation and the delivery of gasses). Extinguish the remaining fire, if any, with saline. Continue anesthesia (via intravenous route). Mask ventilated with 100% FiO2. Perform direct/video laryngoscopy or bronchoscopy to assess the damage and remove debris. Bronchial lavage may be needed to wash out fragments. Re-establish the airway (eg, re-intubate, place a laryngeal mask). Assess for damage to the oropharynx and face. Consider intensive care unit admission and tracheostomy if needed.[2] Risk of Iatrogenic Burns Burns can occur in addition to airway fires, due to accidental exposure of tissues to laser or from the reflection of the laser beam from reflective surfaces in the operative field. The presence of a cuffed ETT limits the possibility of the beam reaching the distal trachea and airway without rupturing the cuff balloon first. Applying saline-soaked gauze to the mucosal areas adjacent to the surgery site is an effective way to prevent such collateral damage. Ocular Injury

Burns can occur in addition to airway fires, due to accidental exposure of tissues to laser or from the reflection of the laser beam from reflective surfaces in the operative field. The presence of a cuffed ETT limits the possibility of the beam reaching the distal trachea and airway without rupturing the cuff balloon first. Applying saline-soaked gauze to the mucosal areas adjacent to the surgery site is an effective way to prevent such collateral damage. Ocular Injury Ocular injuries result from the direct exposure of the eye to the laser or a reflection of the beam. Depending on the physical properties of the laser, several structures can be affected, yet the most commonly involved are the cornea (water-rich) and retina (pigment-rich). Personnel outside the operating room must be warned of using a laser via appropriate signage on the outer surface of all doors to the laser operating room. Any windows in the laser operating room should be covered with opaque coverings. The risk of ocular injury can be significantly decreased by using wavelength-specific filters on safety glasses worn by the patient and operating room personnel.[24] Laser eye injuries are considered an emergency as they can cause permanent blindness. Symptoms include a sensation of a bright flash of colored light and, sometimes, a popping sound matching with the activation of the laser, followed by the loss of visual acuity and the presence of floaters in the visual field.[25] Other laser hazards, like laser plumes, have been shown to have cancerogenic potential. These can be mitigated by using plume scavenging systems and personal high-efficiency filtering masks.[26]

Every healthcare team member must take precautions during laser surgery of the upper airway to avoid harm to themself, the patient, or other operating room personnel. Wear proper protective equipment, which includes a high-efficiency mask and wavelength-specific protective eyeglasses. To decrease the risk of airway fire: Use the lowest concentration of oxygen possible Avoid using nitrous oxide as an anesthetic (at high temperatures, it can release oxygen and act as an oxidizer) Limit laser use to short pulses and the lowest power Activate the laser only when the tip of the laser source is visible, and the endotracheal tube is out of reach of the source. Cover the patient's face and chest with wet towels, and protect the eyes with wavelength-specific eye protection Have saline-filled large (eg, 50 mL) syringes within reach during procedures with a high risk of ignition Know the nearest location of a fire extinguisher and a water source