VOLUME 30, ISSUE 2

Few adverse events are more catastrophic than a fire within the patient’s airway. In this article, we will discuss the causes of airway fires, mitigation and prevention strategies, and management of airway fires and subsequent care of the patient. As will be discussed in greater detail, fires occur when a confluence of elements of the fire triad exist in close proximity [Oxidizers (O2 or N2O), fuels (surgical drape or alcohol-based skin prep), ignition sources (electrocautery or lasers)]. Airway fires are no different, the common presentations of these cases are those where an ignition source such as a monopolar electrosurgical unit (ESU) or a laser is used on tissue within the upper conducting airways or within the trachea when the concentration of oxidizers (oxygen, nitrous oxide) exceeds 30%. Procedures such as tonsillectomy, laser surgeries of the vocal cords and glottic structures, tracheostomy, and endotracheal / endobronchial resections are associated with a higher risk of surgical fire.

With regard to defining a high-risk procedure, the American Society of Anesthesiologists (ASA) does so in their practice advisory concerning operating room fires as any situation where the concentration of oxidizers exceeds 30% in close proximity to an ignition source. When the anesthesiologist encounters a situation where all three elements of the fire triad are present, effective communication is of great importance. Review of recent litigated cases shows that, often, the nidus of a lawsuit is the breakdown of communication between operating room team members. Essential communication includes identification of a high-risk case, identifying steps that can mitigate the risks (reduction of oxidizer concentration, use of an alternative to an ignition source, considering a non-alcohol-based skin prep such as betadine), and assignment of actions to be taken and who should be responsible for those tasks. Of note is the fact that each component of the fire triad is usually managed by a separate entity in the OR. The anesthesia team manages the oxidizers, the nurse and surgical technicians manage fuels, and the surgeon or proceduralist manages ignition sources. This further illustrates the importance of communication between all members of the team. An ideal time to have this conversation is during the procedural time-out or surgical pause. Incorporating a fire risk assessment on the surgical safety checklist is strongly suggested to facilitate this discussion.

When an ignition source is used in the airway, the anesthesiologist should verify with the surgeon that the delivered oxidizer concentration is less than 30%. If the patient’s clinical condition changes and an increase in oxygen concentration is needed, this should be communicated to the surgeon; if time lapses, a reminder of the new oxygen concentration should be expressed prior to the use of an ignition source. Prior to use of an ignition source, oxidizer concentration should be reduced to below 30%. It is paramount to understand that the change of oxidizer concentration does not occur immediately and the dissipation times after the introduction of medical air as a dilution gas is dependent upon fresh gas flow rate. If the flow rates are 6 liters or greater per minute are used, then adequate reduction in oxidizer concentrations can be achieved in about 90 seconds. If flow rates less than 6 liters per minute, then dilution times can exceed 6 minutes.

For procedures in the upper airway, head, or neck in which the patient requires supplemental oxygen, isolation of oxidizing gases used in providing anesthetic care should occur by the use of a properly sized, cuffed endotracheal tube. If properly sized and sealed, the use of a supraglottic airway may be considered, but if the device has a significant leak of gases, then an endotracheal tube is preferred. These measures help decrease the risk of pooling of oxygen beneath the drapes which can accumulate in high concentrations. In the airway distal to the glottis, an oxidizer concentration of less than 30% should be maintained if an ignition source is used. For intermittent jet ventilation, many jet ventilators allow the user to select the FiO2 used for ventilation or an air/ oxygen blender can be used.

When a laser is used in the airway or adjacent structures, a laser tube specific to the type of laser should be utilized. For cuff inflation in these tubes, an indicator dye such as methylene blue may be used to aid in the identification of cuff rupture by laser penetration. Given the nuances of safe patient care for laser cases, use of a cart with a specific laser safety checklist might be beneficial.

Should an airway fire occur, the gas flow to the patient must be stopped and if an endotracheal tube is in place, it must be removed. The conundrum of “which action to do first” is irrelevant, both steps must be completed. Often it is easiest to quickly disconnect the circuit as a means of arresting gas flow to the patient. During head and neck cases, the head of the patient may be at 90 or 180 degrees from the anesthesia workstation, in these cases the surgeon may be in the best proximity to remove the endotracheal tube. These cases further emphasize the need for role establishment and communication prior to a crisis event. After the tube is removed, water or saline should be poured into the airway prior to attempting ventilation. The rationale for this step is to extinguish any smoldering areas which may flame up if further oxygen is delivered by positive pressure ventilation, similar to the use of bellows on a campfire. As soon as feasible, the airway should be protected by an endotracheal tube as airway edema is inevitable.

Patients who have experienced an airway fire should undergo evaluation to assess the significance of the burn injury. Adequate assessment for smoke inhalation and airway injury should be performed. An examination is also needed to look for remnants of the endotracheal tube that may remain in the airway. If thermal injury is likely to have occurred in the lower airways, a rigid bronchoscopy may also be indicated.

After the event has occurred, the fire department should be notified. In Texas, if a person is injured due to a fire, it is required to report the event to the local fire department for investigation by the local or state fire marshal. An appropriate discussion should take place with the family and patient the OR team may wish to incorporate the “TEAM” approach in breaking bad news to the family. Specifically,

• T– Tell the Truth
• E– Demonstrate Empathy (Eye contact, Emotion, Evidence of compassion)
• A– Apologize (with appropriate context: i.e., for the inconvenience, discomfort, unanticipated outcome, and for a mistake, if one occurred)
• M– Management (this is really key: explain to the patient and family what will happen next to deal with the unanticipated outcome).

The experts who analyze anesthesia-related closed-claims data also gather data in the form of feedback from the patient or family members involved. These experts suggest that the TEAM approach is helpful in establishing better communication and mitigating legal risks.

Finally, as in any crisis, there should be a debriefing where the OR team members involved should be able to discuss what was done correctly, where mistakes were made, how the team can support each other, and a plan for further improvement. Using a debrief session after untoward events is essential to reducing depression and guilt feelings that are experienced by team members in these types of events.

Operating room fires are largely preventable with increased education and improved communication between team members. Therefore, we should all strive to create the safest environment in our ORs for the well-being of our patients.