Fire Risks in Airway Procedures: A Clinical Review of Proactive Prevention and Emergency Response.

* Developed by the American Society of Anesthesiologists Task Force on Operating Room Fires: Robert A. Caplan, M.D. (Chair), Seattle, Washington; Steven J. Barker, Ph.D., M.D., Tucson, Arizona; Richard T. Connis, Ph.D., Woodinville, Washington; Charles Cowles, M.D., Deer Park, Texas; Albert L. de Richemond, M.S., P.E., Plymouth Meeting, Pennsylvania; Jan Ehrenwerth, M.D., Madison, Connecticut; David G. Nickinovich, Ph.D., Bellevue, Washington; Donna Pritchard, R.N., Brooklyn, New York; David Roberson, M.D., Boston, Massachusetts; Gerald L. Wolf, M.D. (Honorary), Brooklyn, New York.PRACTICE advisories are systematically developed reports that are intended to assist decision making in areas of patient care. Advisories are based on a synthesis of scientific literature and analysis of expert opinion, clinical feasibility data, open forum commentary, and consensus surveys. Advisories developed by the American Society of Anesthesiologists (ASA) are not intended as standards, guidelines, or absolute requirements. They may be adopted, modified, or rejected according to clinical needs and constraints.The use of practice advisories cannot guarantee any specific outcome. Practice advisories summarize the state of the literature and report opinions obtained from expert consultants and ASA members. Practice advisories are not supported by scientific literature to the same degree as standards or guidelines because of the lack of sufficient numbers of adequately controlled studies. Practice advisories are subject to periodic revision as warranted by the evolution of medical knowledge, technology, and practice.The incidence of operating room (OR) fires is difficult to determine, due in part to the lack of a mandatory national reporting system for OR fires.1–3Some estimates suggest that between 50 and 200 OR fires occur in the United States every year, with as many as 20% of reported fires resulting in serious injury or death.4,5Fire requires the presence of three components, known as the “fire triad”: (1) an oxidizer, (2) an ignition source, and (3) fuel.For this Advisory, operating room fires are defined as fires that occur on or near patients who are under anesthesia care, including surgical fires, airway fires, and fires within the airway circuit. A surgical fire is defined as a fire that occurs on or in a patient. An airway fire is a specific type of surgical fire that occurs in a patient's airway. Airway fires may or may not include fire in the attached breathing circuit.A high-risk procedure is defined as one in which an ignition source (e.g. , electrosurgery) may come in proximity to an oxidizer-enriched atmosphere (e.g. , supplemental oxygen and/or nitrous oxide), thereby increasing the risk of fire. Examples of high-risk procedures include, but are not limited to, tonsillectomy, tracheostomy, removal of laryngeal papillomas, cataract or other eye surgery, burr hole surgery, or removal of lesions on the head, neck, or face.An OR fire drill is defined as a formal and periodic rehearsal of the OR team's planned response to a fire. In this Advisory, the OR fire drill is characterized as a “formal and periodic rehearsal” to indicate that it takes place during dedicated education time, not during patient care . In other words, an OR fire drill is not the same as a discussion or plan about fire management that takes place during direct patient care.The purposes of this Advisory are to (1) identify situations conducive to fire, (2) prevent the occurrence of OR fires, (3) reduce adverse outcomes associated with OR fires, and (4) identify the elements of a fire response protocol. Adverse outcomes associated with OR fires may include major or minor burns, inhalation injuries, infection, disfigurement, and death. Related adverse outcomes may include psychological trauma, prolonged hospitalization, delay or cancellation of surgery, additional hospital resource utilization, and liability.This Advisory focuses on a specific care setting and subset of fires. The specific care setting is any OR or procedure area where anesthesia care is provided. The specific subset is fires that occur on the patient, in the airway, or in the breathing circuit. This Advisory does not address fires away from the patient (e.g. , in a trash can), institutional preplanning for fire, or the responses of fire personnel.This Advisory is intended for use by anesthesiologists or other individuals working under the supervision of an anesthesiologist. Because prevention of OR fires requires close collaboration and prompt coordination between anesthesiologists, surgeons, and nurses, some responsibilities are shared among the disciplines. When shared responsibilities are described in this Advisory, the intent is to give the anesthesiologist a starting point for participating in the allocation and understanding of shared responsibilities. The Advisory may also serve as a resource for other physicians and healthcare professionals (e.g. , technicians, safety officers, hospital administrators, biomedical engineers, industry representatives).The ASA appointed a Task Force of nine members. These individuals included four anesthesiologists in private and academic practice from various geographic areas of the United States, an otolaryngologist, a perioperative registered nurse, a professional engineer/fire investigator, and two consulting methodologists from the ASA Committee on Standards and Practice Parameters. Two Task Force members are former firefighters.The Task Force developed the Advisory by means of a seven-step process. First, they reached consensus on the criteria for evidence. Second, a systematic review and evaluation was performed on original, published, peer-reviewed and other research studies related to OR fires. Third, a panel of expert consultants was asked to (1) participate in opinion surveys on the effectiveness of various strategies for fire prevention, detection, and management and (2) review and comment on a draft of the Advisory developed by the Task Force. Fourth, opinions about the Advisory were solicited from a random sample of active members of the ASA. Fifth, the Task Force held an open forum at a major national meeting‡to solicit input on its draft recommendations. Sixth, the consultants were surveyed to assess their opinions on the feasibility of implementing this Advisory. Seventh, all available information was used to build consensus within the Task Force to formulate the advisory statements (appendix 1).Preparation of this Advisory followed a rigorous methodological process (appendix 2). Evidence was obtained from two principal sources: scientific evidence and opinion-based evidence.Study findings from published scientific literature were aggregated and are reported in summary form by evidence category, as described below. All literature (e.g. , randomized controlled trials, observational studies, case reports) relevant to each topic was considered when evaluating the findings. However, for reporting purposes in this document, only the highest level of evidence (i.e. , level 1, 2, or 3) within each category is included in the summary.Randomized controlled trials report statistically significant (P < 0.01) differences between clinical interventions for a specified clinical outcome.Information from observational studies permits inference of beneficial or harmful relationships among clinical interventions and clinical outcomes.The literature cannot determine whether there are beneficial or harmful relationships among clinical interventions and clinical outcomes.The lack of scientific evidence in the literature is described by the following terms.All opinion-based evidence relevant to each topic (e.g. , survey data, open-forum testimony, Web-based comments, letters, editorials) is considered in the development of this Advisory. However, only the findings obtained from formal surveys are reported.Opinion surveys were developed by the Task Force to address each clinical intervention identified in the document. Identical surveys were distributed to two groups of respondents: expert consultants and ASA members.Survey responses from Task Force-appointed expert consultants are reported in summary form in the text. A complete listing of consultant survey responses is reported in appendix 2.Survey responses from a random sample of members of the ASA and, when appropriate, responses from members of other organizations with expertise in the selected topics of interest are reported in summary form in the text. A complete listing of ASA member survey responses is reported in appendix 2.Survey responses are recorded using a five-point scale and summarized based on median values.∥Open-forum testimony, Web-based comments, letters, and editorials are all informally evaluated and discussed during the development of the Advisory. When warranted, the Task Force may add educational information or cautionary notes based on this information.Operating room fire safety education includes, but is not limited to, knowledge of institutional fire safety protocols and participation in institutional fire safety education. Case reports indicate that lack of education can result in severe injury and death from uncontrolled OR fires.6,7[Category B3 evidence.]The consultants and ASA members strongly agree that every anesthesiologist should have knowledge of institutional fire safety protocols for the OR, and should participate in OR fire safety education. The consultants and ASA members strongly agree that OR fire safety education for the anesthesiologist should emphasize the risk created by an oxidizer-enriched atmosphere.All anesthesiologists should have fire safety education, specifically for OR fires, with emphasis on the risk created by an oxidizer-enriched atmosphere.A case report indicates that OR fire drills and simulation training can result in improved staff response to a fire.8[Category B3 evidence.]The consultants strongly agree and ASA members agree that all anesthesiologists should periodically participate in OR fire drills with the entire OR team. The consultants and ASA members strongly agree that participation should take place during dedicated educational time, not during patient care.Anesthesiologists should periodically participate in OR fire drills with the entire OR team. This formal rehearsal should take place during dedicated educational time, not during patient care.Preparation for OR fires includes (1) determining whether or not a high-risk situation exists and (2) a team discussion of the strategy for the prevention and management of an OR fire in a high-risk situation. The literature is silent regarding whether a preoperative determination of a high-risk situation or a team discussion of OR fire strategy reduces the incidence or severity of an OR fire. [Category D evidence.]The consultants strongly agree and ASA members agree that anesthesiologists should participate with the entire OR team in assessing the risk of an OR fire for each case and determining whether a high-risk situation exists. The consultants strongly agree and ASA members agree that all team members should jointly agree on how a fire will be prevented and managed for each particular procedure. The consultants and ASA members strongly agree that a protocol for the prevention and management of fires should be posted in each location where a procedure is performed.For every case, the anesthesiologist should participate with the entire OR team (e.g. , during the surgical pause) in determining whether a high-risk situation exists. If a high-risk situation exists, all team members—including the anesthesiologist—should take a joint and active role in agreeing on how a fire will be prevented and managed. Each team member should be assigned a specific fire management task to perform in the event of a fire (e.g. , removing the tracheal tube, stopping the flow of airway gases). Each team member should understand that his or her preassigned task should be performed immediately if a fire occurs, without waiting for another team member to take action. When a team member has completed a preassigned task, he or she should help other team members perform tasks that are not yet complete.In every OR and procedure area where a fire triad can exist (i.e. , an oxidizer-enriched atmosphere, an ignition source, and fuel), an easily visible protocol for the prevention and management of fires should be displayed (fig. 1).Equipment for managing a fire should be readily available in every procedural area where a fire triad may exist. Table 1provides an example of fire management equipment that should be in or near the OR or procedural area.Prevention of OR fires includes (1) minimizing or avoiding an oxidizer-enriched atmosphere near the surgical site, (2) safely managing ignition sources, and (3) safely managing fuels.Comparative studies indicate that a wide range of material ignites more readily in an oxygen-enriched atmosphere than in room air.9–13[Category B1 evidence.] One comparative study with awake volunteer subjects showed that the configuration of surgical drapes can result in oxygen buildup, increasing the risk of fire.14[Category B1 evidence.] This study also indicated that replacing oxygen with compressed air or discontinuing supplemental oxygen for a period of time reduces oxygen buildup without significantly reducing oxygen saturation levels. Similarly, a randomized controlled trial comparing supplemental oxygen and compressed air in sedated patients undergoing cataract surgery found no differences in oxygen saturation.15[Category C2 evidence.]Observational studies and case reports indicate that electrocautery or electrosurgical devices and lasers are common sources of ignition for many OR fires, particularly when used in an oxidizer-enriched atmosphere.16–68[Category B2–3 evidence.]Case reports indicate that alcohol-based skin-prepping agents generate volatile vapors that ignite easily. These reports suggest that insufficient drying time after application of alcohol-based skin-prepping agents is a cause of fires on patients.23,69–73[Category B3 evidence.] Comparative studies show that conventional tracheal tubes, when exposed to a laser beam, are more likely to ignite or melt than laser-resistant tracheal tubes.74–84[Category B1 evidence.] Case reports indicate that dry sponges and gauze are common sources of fuel.7,19,33,43,45,55,64,83–87Comparative studies demonstrate that the flammability of sponges, cottonoids, or packing material is reduced when wet rather than dry or partially dry.88–91[Category B1 evidence.]For all procedures , the consultants and ASA members strongly agree that flammable skin prepping solutions should be dry before draping. They strongly agree that surgical drapes should be configured to prevent oxygen from accumulating under the drapes or from flowing into the surgical site. They strongly agree that sponges should be moistened when used near an ignition source, particularly when used in or near the airway.For high-risk procedures (i.e. , proximity of an ignition source and an oxidizer-enriched atmosphere), the consultants and ASA members strongly agree that anesthesiologists should collaborate with the procedure team for the purpose of preventing and managing a fire. They strongly agree that the surgeon should be notified whenever an ignition source is in proximity to an oxidizer-enriched atmosphere or when the concentration of oxidizer has increased. They strongly agree that the fraction of inspired oxygen (Fio2) delivered to the patient should be kept as low as clinically feasible when an ignition source is in proximity to an oxygen-enriched atmosphere. They strongly agree that the reduction of Fio2delivered to the patient should be guided by monitoring patient oxygenation (e.g. , pulse oximetry). Task Force members agree that the reduction of Fio2should be monitored, if feasible, by measuring inspired, expired, and/or delivered oxygen concentration. They strongly agree that the use of nitrous oxide should be avoided in settings that are considered high risk for fire. The consultants strongly agree and ASA members agree that oxygen or nitrous oxide buildup may be minimized by either insufflating with medical air or scavenging the operating field with suction.For laser surgery , consultants and ASA members strongly agree that laser resistant tracheal tubes should be used, and that the tube choice should be appropriate for the procedure and laser. They both strongly agree that the tracheal cuff of the laser tube should be filled with saline rather than air, when feasible. The consultants strongly agree and the ASA members agree that saline in tracheal tube cuff should be tinted with methylene blue to act as a marker for cuff puncture by a laser.Surgery inside the airway can bring an ignition source into proximity with an oxidizer-enriched atmosphere, thereby creating a high-risk situation. For cases involving surgery inside the airway, consultants and ASA members both agree that a cuffed tracheal tube should be used instead of an uncuffed tracheal tube when medically appropriate. Because an elevated Fio2is often necessary during tracheostomy, the Task Force strongly agrees that surgeons should be advised not to enter the trachea with an ignition source such as an electrosurgical device. If an electrosurgical device must be used, the anesthesiologist should request that the surgeon provide adequate warning to allow the concentration of oxidizer to be minimized before the trachea is entered. Consultants and ASA members were asked to report the time that they believe is needed to reduce oxygen or nitrous oxide concentration to a safe level before using an ignition For patients with a tracheal tube, consultants report a range of time of than to and ASA members report a range of time of than to For patients a or both the consultants and ASA members report a range of time of than to for and for ASA The consultants and ASA members both agree that the should be with during the head, or can bring an ignition source into proximity with an oxidizer-enriched atmosphere, thereby creating a high-risk situation. When anesthesia care is considered for surgery the head, or neck, the Task Force strongly agrees that two specific should be (1) the of and (2) oxygen . The Task Force agrees that a device (e.g. , cuffed tracheal tube or laryngeal should be considered if or is or used, or if the patient oxygen . If is an open device (e.g. , or may be If an open system is used, the Task Force agrees that before an ignition source is the head, or neck, the surgeon should give the adequate that the ignition source will be The anesthesiologist should (1) the of supplemental oxygen or reduce the to the to and (2) a between the flow of supplemental oxygen and the of the ignition In the event of nitrous oxide with an open system (e.g. , or the Task Force agrees that the anesthesiologist should (1) the of nitrous and (2) a between stopping the nitrous oxide and the of the ignition the that is medically appropriate, the following should be to the management of ignition sources, and high-risk procedures , the anesthesiologist should the surgeon whenever there is a for an ignition source to be in proximity to an oxidizer-enriched atmosphere or when there is an in oxidizer concentration at the surgical site. reduction in oxygen to the patient should be by monitoring (1) pulse and, if feasible, (2) inspired, and/or delivered oxygen laser procedures , a laser-resistant tracheal tube should be used, and the tube should be to be resistant to the laser used for the procedure (e.g. , The tracheal cuff of the laser tube should be filled with saline and with an such as methylene a the surgeon should give the anesthesiologist adequate that the ignition source is about to be The anesthesiologist should (1) reduce the delivered oxygen concentration to the to (2) the use of nitrous and (3) a after reducing the oxidizer-enriched atmosphere before of the cases involving an ignition source and surgery inside the airway , cuffed tracheal tubes should be used when clinically appropriate. The anesthesiologist should the surgeon the trachea with an ignition source (e.g. , an ignition source inside the airway, the surgeon should give the anesthesiologist adequate that the ignition source is about to be The anesthesiologist should (1) reduce the delivered oxygen concentration to the to (2) the use of nitrous and (3) a after reducing the oxidizer-enriched atmosphere before the of the ignition In some cases (e.g. , surgery in the scavenging with may be used to reduce oxidizer in the cases involving or , an ignition source , and surgery the head, or , the anesthesiologist and surgeon should a plan that for the level of and the patient's for supplemental of OR fires includes (1) the of fire, (2) the (3) making appropriate to the fire, (4) following an protocol when medically appropriate, and care to the reports indicate that of a fire may include a or or B3 evidence.] One case report indicates that removing the tracheal tube and stopping the flow of oxygen can patient B3 evidence.] One case report that saline into the patient's tracheal tube was in the B3 evidence.] One case of a patient death from an OR fire indicated that fire were available but not used by the OR staff on the warning of a fire are the consultants and ASA members strongly agree that there should be an to the procedure. When a fire is the consultants and ASA members strongly agree that there should be an of fire, followed by an to the a fire in the airway or breathing , the consultants and ASA members strongly agree as as the tracheal tube should be and all flammable and should be from the airway. The consultants strongly agree and ASA members agree that the of all airway should and they both agree that saline should be into the patient's airway to any and the a fire on or in the patient , the consultants agree and ASA members are regarding whether the of all airway should They both strongly agree that all and flammable all should be from the patient, and that all or the patient should be (e.g. , with or a fire of the consultants and of the ASA members indicated that the means for safely to an OR fire is for each team member to immediately perform a fire management task in a . of the consultants and of the ASA members indicated that the means of safely to an OR fire is for each team member to immediately perform a preassigned task, without waiting for to The Task Force that a of tasks can be when a fire occurs, but that team members should not for each other if there are to following the of tasks in a . The Task Force agrees that a team member who has completed a preassigned task may assist another team member task is not yet the to the fire or the patient is not the consultants and ASA members both agree that a should be If fire after use of a consultants and ASA members both strongly agree that the fire should be and the patient should be if feasible. The consultants and ASA members both agree that the to the room should be and not The consultants strongly agree and the ASA members agree that the medical to the room should be after consultants and ASA members strongly agree that after a fire has the patient's should be and a plan should be for care of the patient. When an airway or breathing fire has consultants and ASA members both agree that should be avoiding supplemental oxygen and nitrous if the consultants and ASA members strongly agree that the tracheal tube should be to assess whether have in the airway. The consultants strongly agree and the ASA members agree that should be considered to assess for tracheal tube and in the removal of If the fire not the airway and the patient was not before the fire, the consultants and ASA members both strongly agree that the patient should be for injury related to an warning is the procedure and for an evaluation of fire. of a fire may include (e.g. , a or of of drapes or breathing patient or and or a fire is immediately the fire, the and fire management members should perform their preassigned fire management tasks as as the the team may identify a for the If a team member cannot perform his or her task in the other team members should perform their tasks without waiting . When a team member has completed a preassigned task, he or she should help other members perform tasks that are not yet following are in an that the team may to in its discussion of a a fire in the airway or breathing , as as a fire on or in the patient , as as the airway or breathing fire is the fire on or in the patient is the fire is not after the (e.g. , after the preassigned reporting (e.g. , report fires to fire and state of every fire as an adverse following institutional this Advisory, a literature review was used in with opinions obtained from and other sources (e.g. , professional open Web-based to provide to regarding OR fire prevention and the literature review and opinion were based on evidence , or statements regarding relationships between fire prevention and management interventions and OR fire evidence interventions are safety education, with an emphasis on an oxidizer-enriched participation in OR fire of an easily visible protocol for the prevention and management of determination of a high-risk OR team discussion of OR fire configuration to the of of flammable skin prepping of sponges and gauze when used in proximity to an ignition the concentration of oxygen for high-risk of nitrous oxide for high-risk uncuffed tracheal tubes for cases in or the with medical air during cases in or the with during cases in or the tracheal tubes during laser the tracheal cuff of the laser tube with saline with an of a fire include a or or the tracheal tube and stopping the flow of oxygen to patient injury after an airway or breathing saline into the patient's tracheal tube to an airway the literature relevant studies were identified and of the The literature a period from than were a of that topics related to the evidence and criteria for review of the studies not provide direct evidence and were A of direct evidence studies with and information to a analysis (i.e. , among Task Force members and two methodologists was by using a for were as (1) type of study (2) type of (3) evidence and (4) literature for were (1) study (2) type of (3) and (4) literature These to high of was obtained from sources, including (1) survey opinion from consultants who were selected based on their knowledge or expertise in OR fire prevention and (2) survey opinions solicited from active members of the (3) from of a held open forum at a national anesthesia (4) commentary, and Task Force opinion and The survey of was of for the and surveys were from active ASA members. of the surveys are reported in and in the of the consultants were asked to indicate if of the evidence their clinical if the Advisory was The of was of The of consultants a in their practice associated with each topic was as (1) education, (2) OR fire (3) team discussion of fire (4) minimizing or avoiding an oxidizer-enriched atmosphere near the surgical site, managing ignition sources, managing of a high-risk management of a high-risk and OR fire of the indicated that the Advisory have no on the of time on a case, and indicated that there be an of in the of time on a case with the of this Advisory.

Fires and explosions

Fire in Labor and Delivery: Simulation Case Scenario

We read with interest the systematic review and meta-analysis of the effect of high-flow nasal oxygen on hypoxaemia during procedural sedation [1]. While the benefits have been apparent to most anaesthetists that have had the opportunity to use this therapy, we believe that no review of a new therapy is complete without at least mentioning potential hazards. It has long been known that the use of supplementary nasal oxygen during procedural sedation presents a potential risk for airway fires, even at low flow [2]. While none of the studies included in this most recent review had a potential source of ignition (i.e. diathermy or laser), and may have been outside the scope of the review [1], the serious nature of airway fires is an important adverse event to include in future studies assessing high-flow nasal oxygen during procedural sedation. Despite some reassuring experimental reports of the diffusion of high-flow oxygen [3], personal experience with a self-limiting and extremely brief operating theatre fire leading to the explosive removal of a patient's eyebrow has made us aware of the potential dangers. While the risk and prevention of surgical fires has been recently reviewed elsewhere [4], all involved in the use of high-flow nasal oxygen should pay particular attention to fuel and ignition sources including, but not limited to, alcoholic preparations; surgical drapes; patient hair; patient clothing; diathermy; and laser. The pooling of oxygen or fuel under drapes further increases the risks. Mitigating the risk of airway fires has been outlined in a joint guideline by the Association of Anaesthetists and the Intensive Care Society [5]. This includes operating theatre design to reduce oxygen enriched environments; avoiding the use of emollients and oil or alcohol-based products; and training in response to airway fires. Finally, the guideline recommends performing regular reviews of local practices when using diathermy or laser with high-flow nasal oxygen, with the laser protection supervisors and clinical laser experts.

It is generally accepted that when an ignition source is used the inspired oxygen concentration (FIO2) should be <30% in the breathing circuit to help prevent airway fires. The time and conditions required to reduce a high O2% in the breathing circuit to <30% has not yet been systematically studied. We evaluated the inspired and expired circuit oxygen concentration response times of an Aestiva Avance S/5 anesthesia machine to reach an FIO2 of <30% from a starting FIO2 of 100% and 60% after reducing the FIO2 to 21%. The circuit was connected to a human patient simulator which has a functional residual capacity of 2 L, total lung capacity of 2.8 L, an oxygen consumption of 200 mL/min, and respiratory quotient of 0.8. Fresh gas flow (FGF) inputs of 2 L/min and 5 L/min were chosen to represent a spectrum of typical clinical FGF rates. Minute ventilation was set at 4 L/min. Determining the requisite median time to reach an O2 concentration of <30% in the breathing circuit was the primary aim of the study. The median times (1st-99th percent confidence interval) required to achieve inspiratory and expiratory oxygen concentrations of <30% with the extended circuit configuration when starting at 60% for 5 L FGFs were 35 (32-36) and 104 (88-122) seconds, respectively. With 2 L FGF, these median times increased to 303 (291-313) and 255 (232-278) seconds, respectively. A shortened circuit configuration (P = 0.006) and higher FGF flow rate (P < 0.0001) were noted to be factors decreasing the median time required to achieve an oxygen concentration of <30%. Both inspired and expired circuit oxygen concentration may take minutes to decrease to <30% depending on circuit length, FGF rate, and starting circuit oxygen concentration. During the reduction in FIO2, the expiratory oxygen concentration may be >30% for a considerable time after the FIO2 is in a "safe" range. An increased expired oxygen concentration should also be considered an airway fire risk, and patient care protocols may need to be modified based on future studies.

Fires and explosions

Airway fires during laser surgery in Indian operation theaters are rare yet catastrophic, and most hospitals usually do not include laser airway fire prevention and management in their routine healthcare training programs. To develop, implement, and assess the efficacy of an Interprofessional Simulation module for operating room (OR) personnel to prevent and manage airway fires in the OR. A mixed-method study was conducted among an interprofessional OR team comprising anaesthesiology and ENT residents, nurses, and allied health practitioners. Thirty-one participants were immersed in both didactic lectures and in situ simulation scenarios. Validated pre- and posttest 1 questionnaires were given after didactic lectures, and a repeat posttest 2 questionnaire was given after the simulation. Team performance and communication skills were assessed using a validated observer checklist before and after the scenarios. The debriefing session postsimulation was audio-recorded and transcribed for thematic analysis. Attitude toward the IPSE module was assessed using the Retro-Pre validated questionnaire. Quantitative data analysis revealed significant improvement in all three domains of knowledge (P = 0.001), attitude (P = 0.001), and performance towards the IPSE module (P = 0.012). Participants retained the knowledge, simulation scores on prevention and management, and significant improvement in team performance (P = 0.041) even after 6 months. Common themes such as defined roles, critical decision-making, collective troubleshooting, shared leadership, enhanced communication, realism, confidence gains, and learning from mistakes toward interprofessional simulation training were highlighted in the qualitative analysis done. Implementing an IPSE module has shown promising results for enhancing knowledge and team performance in the prevention and management of laser airway fires.

Airway fires during tracheotomy are rare but potentially fatal events, which are preventable. There are many surgical procedures that place the patient at a higher risk for airway fires, identification of those procedures and the associated risk is the first step towards avoiding this deadly complication. In this chapter the fire triad, of which each of the three components is independently necessary for fire to occur is described. Operating room fire safety measures are reviewed, with emphasis on the management of airway fires. The immediate interventions during an airway fire are discussed, together with the dilemma of which method should be used to secure the airway after the endotracheal tube catches fire.

MTE 19.01 Laser Therapy for Airway Obstruction

Airway fires pose a serious risk to surgical patients. Fires during surgery have been reported for many years with flammable anesthetic agents being the main culprits in the past. Association of airway fires with laser surgery is well-recognized, but there are reports of endotracheal tube fires ignited by electrocautery during pharyngeal surgery or tracheostomy or both. This uncommon complication has potentially grave consequences. While airway fires are relatively uncommon occurrences, they are very serious and can often be fatal. Success in preventing such events requires a thorough understanding of the components leading to a fire (fuel, oxidizer, and ignition source), as well as good communication between all members present to appropriately manage the fire and ensure patient safety. We present a case of fire in the airway during routine adenotonsillectomy. We will review the causes, preventive measures, and brief management for airway fires.

An airway fire is a surgical fire that occurs in a patient’s airway and may or may not include a fire in the attached breathing circuit. It is estimated that 217 to 650 operating room fires occur each year in the United States, with as many as 5% to 10% associated with serious injury or death. Airway fires are particularly harmful to patients, constituting approximately 21% of all surgical fires and the majority of surgical fires that result in death. A fire requires three components known as the “fire triad”: an oxidizer, an ignition source, and a fuel. The earliest signs of a fire are seeing a flash, hearing a pop, or smelling smoke. The major steps in the management of an airway fire are to extinguish the fire, stabilize the patient, and assess the patient’s airway for fire damage to decide whether the patient needs to be intubated and remain intubated.

Background Airway surgery utilizing a heat source carries a risk of airway fire. Among the airway fire triad of oxidizer, fuel, and ignition source, oxygen concentration is a modifiable risk factor. Rigid bronchoscopy, commonly used during airway surgery, utilizes an open circuit. An open circuit, when combined with jet ventilation, makes measurement of airway oxygen concentration difficult. To decrease airway oxygen concentration, some centers use a pause in jet ventilation to allow airway concentration to decrease; however, the effect of this pause on central airway oxygen levels is not known.Our objective was to better understand changes in central airway oxygen concentration during apnea during rigid bronchoscopy, an important component of fire risk. Methods We designed a prospective observational study of patients requiring rigid bronchoscopy. We utilized jet ventilation with 100% FiO2. To measure central airway oxygen concentration in the distal trachea, we connected a long rigid suction cannula to an oxygen analyzer and passed it through the bronchoscope. When central airway oxygen concentration was >90%, apnea was initiated, and we measured the time required for central airway oxygen concentration to decrease to less than 40%. This was repeated for the right and left main bronchi. Results The average time to reach airway oxygen concentration of less than 40% was 40.9±18.1s (mean±SD), 41.9±19.5s, and 41.6±21.7s for the trachea, right main bronchus, and left main bronchus, respectively. Conclusions We found that after a prolonged period of apnea, many patients had central airway oxygen concentration above levels conventionally considered optimal for airway surgery. This is the first description of this method for monitoring central airway oxygen concentration.

We all believe that we know about fire safety and rarely think about having a fire in the dental chair that could cause serious injury or death to a patient. Yet fires are not uncommon in hospital operating rooms and also have occurred in dental offices. It is estimated that 600 surgical fires occur yearly in hospitals.1 Although hospitals are required by the Joint Commission to report fires, we do not know whether such incidences are increasing in dental offices. We do know that they can be devastating to both the patient and the doctor. So how can the individual dentist improve the margin of safety to prevent such a disaster from occurring? We all need to be aware that we must control a number of fire risk factors that are ever present during dental treatments, especially those involving sedation or general anesthesia where oxygen is delivered.It is common knowledge that fires require three essential ingredients, the so-called fire triangle: a source of fuel, a source of heat sufficient to cause ignition, and the presence of oxygen (or any other oxidizer such as nitrous oxide). Each side of the fire triangle contains obvious (and some not-so-obvious) components that are commonly found in the dental office or operating room. Although we understand that fire can be prevented by taking away any one of the three elements, we also know that modern dental treatments, especially involving sedation or general anesthesia, often require the presence of all three of the triangle's components to facilitate a good surgical outcome. Thus our goal is to keep them as far apart as reasonably possible, but that can be very difficult since dentists are usually working in and around the airway, where oxygen abounds.Common materials used in dentistry, such as tape, gauze packs, cotton rolls, throat screens, and sterile drapes and towels, are all obvious sources of fuel for a fire. If possible, these fuels must be kept moist throughout the procedure to reduce their flammability. Headrest covers, egg-crate foam padding, rubber dams, nasal cannulas, oxygen masks, nasal hoods, and endotracheal tubes are also sources of fuel and should be shielded from accidentally coming in contact with a heat source such as a laser. Moist sterile towels can be placed over water-resistant paper sterile drapes or other non–water-absorbing materials to protect them from igniting. Adhesive clear plastic incise drapes are flammable in oxygen-enriched environments. Some less obvious sources of fuel include the material covering fiber-optic cables, BIS monitor cables and pads, and ECG wires. Skin prep solutions containing a significant amount of alcohol are supposed to dry before the procedure is started, but especially when they soak into drapes and towels or pool beneath the neck, vapors from these solutions can collect under sterile drapes and have been known to result in a ball of flames when ignited by a source of intense heat in an oxygen-rich atmosphere. Aerosol adhesives and liquids such as tincture of benzoin (75–80% alcohol) are highly flammable fuels. While a large glob of petroleum jelly (Vaseline) or antibiotic ointment might absorb considerable heat before vaporizing and igniting, a thin coat on the lips or skin needs less heat to ignite, especially in the presence of high concentrations of oxygen. Hair, including facial hair, hair nets, and caps, is another commonly neglected source of fuel that is in close proximity to oral surgical procedures. Water-based lubricants, such as K-Y jelly, are primarily water and will not burn since heat vaporizes the water in the lubricant and cools the area. Water-based lubricants can actually be used to coat hair to make it more fire resistant. Any measure that will reduce the contact of fuel with the other two components of the fire triangle or reduce their flammability will increase the margin of fire safety.Electrocautery, electrosurgery, and laser units, as well as fiber-optic light units and cables, are very common sources of intense heat in the dental office. Even sparks from a high-speed drill contacting hard tissue or metal plates and screws can ignite a fire if a dry gauze throat screen and a high concentration of oxygen are present. It would be difficult to eliminate all of the very useful and necessary heat-producing devices and tools from modern dental practices in order to eliminate the possibility of a fire. To help prevent an intraoperative fire, we must treat these instruments as we would a loaded gun and be continually aware that we cannot allow even a brief lapse in safety precautions. For instance, when not in use, even for a few seconds, cautery handpieces must always be kept in their holsters rather than being briefly placed directly on the patient's drapes. The surgeon should be the only one to activate the device and only when its tip is in his or her direct view. Contaminated tips must be disconnected and removed from the surgical field, lest they be accidentally activated. Keep only those necessary foot-activated switches in the surgical area and keep them as far away from each other as possible to prevent activating the wrong one. Keep fiber-optic light sources in the standby mode or turned off when disconnecting the cables and never place the cables on the drapes or on other flammable materials.The administration of supplemental oxygen to patients during sedation and general anesthesia would be difficult to entirely eliminate because respiratory complications due to hypoxemia are the single most likely cause of serious morbidity and mortality associated with sedation and general anesthesia. Supplemental oxygen given during deep sedation or general anesthesia before a laryngospasm or upper airway obstruction occurs increases the time available to correct the problem before life-threatening hypoxemia develops. However, the administration of oxygen does increase the risk of an intraoperative fire. In fact, in vitro studies simulating operating room fires indicate that without an oxygen-enriched environment, many flammable materials used in surgery that come in contact with an intense heat source tend to initially smolder before developing a flame, or they might even self-extinguish. However in an oxygen-enriched environment, a flash fire can occur and cause tremendous damage before the surgical team can react. Supplemental oxygen can build up in high concentrations under surgical drapes when tented over a patient's head, and they can travel great distances under the drapes and exit near a remote surgical site such as a hip graft harvesting area. When this oxygen is combined with a fuel and even just a spark as an ignition source, a tremendous ball of fire can erupt. Therefore, it is recommended that we reduce the concentration or even completely eliminate supplemental oxygen if medically acceptable when an intense heat source must be used near a fuel. Anesthesia machines that can deliver air as well as oxygen can provide a modest oxygen concentration of perhaps 30% that will maintain an acceptable pulse oximeter reading while reducing the potential for a flash fire. Since thermal decomposition of nitrous oxide liberates oxygen, diluting the oxygen with nitrous oxide is not helpful. In dental offices, one could stop the flow of supplemental oxygen for a minute and ensure that oxygen is not trapped under the surgical drapes before the cautery or laser is used, particularly if a potential source of fuel is in proximity to the heat.The Emergency Care Research Institute, an independent, nonprofit organization that researches the best approaches for improving the safety, quality, and cost-effectiveness of patient care, published the following case report2:This sobering case report clearly illustrates that this could have easily been in your office or my operating room. Should a fire occur despite our best efforts, we must recognize that the initial burn is typically much worse than what it looks like soon after the fire is extinguished. What may at first appear to be a mild sunburn can result in a significant injury. Furthermore, an inhalation fire injury can be quickly fatal. I strongly urge all of our readers to reevaluate their dental practices to see where they can improve on fire safety. While it is not reasonable or wise to abandon the use of oxygen in the office, it must be used carefully to avoid a fire in the dental chair. Let's not depend on our past good luck to prevent a fire in the future.

Background: A surgical fire is a rare but life-threatening event. They are always unexpected and commonly occur in head and neck surgeries resulting in severe burns, disfigurement, and in some cases death. Injuries are not limited to patients alone as they may also involve health-care personnel in the operating theater. There is a resurgence in the awareness of this intra-operative challenge as well as an understanding of the need for a team approach to prevention. Materials and Methods: The surgical fire triangle is a useful paradigm that describes the three elements necessary for initiation of a surgical fire i.e., ignition source, fuel, and an oxidizer. This review will identify operating theatre contents capable of acting as ignition/oxidizer/fuel sources and highlight the management and prevention of surgical fires. Results: Surgical fires can be prevented by education across all professional boundaries in the operating theater. This will entail information on how the elements of the fire triangle interact, recognizing how standard operating room equipment can initiate a fire, and vigilance for the circumstances that increase the likelihood of a surgical fire. Conclusion: Promoting a culture of fire safety in the theater is not optional. Education on the prevention of surgical fires should be included in the curriculum of undergraduate medical students. There is an urgent need to stimulate debate within National burn associations in this context, leading to the formation of proposals to be incorporated into existing National burn prevention plans.

High-flow nasal oxygen (HFNO), or transnasal humidified rapid-insufflation ventilatory exchange (THRIVE), is a technique providing apneic oxygenation and a degree of ventilation during microlaryngeal surgery. Its use with laser has been questioned due to concern for airway fire. For fire to occur, a triad of ignition source, oxidizer, and fuel source must be present. By using HFNO and eliminating an endotracheal tube (fuel source), it is hypothesized that airway fire risk is minimal. We tested this theory with human cadavers using HFNO with increasing levels of FiO2 while performing microlaryngeal laser surgery. HFNO was placed on two cadavers, and oxygen was administered at incrementally increasing fraction of inspired oxygen (FiO2) concentrations (30%-100%). Laryngeal microsurgery was conducted with CO2 and KTP lasers applied for 30 s. Oxygen readings were taken at several anatomic locations along the body assessing oxygen concentrations in correlation with increasing FiO2 administration. The use of CO2 and KTP laser on cadaveric vocal folds produced char but no spark or airway fire at any of the tested oxygen concentrations. Apart from the mouth, there was minimal increase in oxygen levels at the surrounding anatomic sites despite elevating FiO2 levels. HFNO may be safe to use during microlaryngeal laser surgery. By eliminating the endotracheal tube as a fuel source, risk of airway fire may be negligible. Our study safely applied CO2 and KTP lasers for an uninterrupted 30 s with HFNO at 70 L/min and 100% FiO2 producing no spark or fire. NA Laryngoscope, 135:223-226, 2025.