Fire safety in the operating room

INTRODUCTION — 

A fire in the operating room (OR) is a relatively rare event. However, when a fire does occur the medical outcomes may be catastrophic if a patient is injured, with severe legal and economic consequences for the surgical team and facility.

Most OR fires are preventable with communication, appropriate education, and risk management [1,2]. Since these preventive measures have little cost and are nearly 100 percent effective, they are prioritized in patient safety initiatives.

This topic will review causes, high-risk settings, and prevention of fires in the OR, as well as acute management of a surgical fire and the burned patient.

INCIDENCE AND IMPACT OF OPERATING ROOM FIRES

●Incidence – Reports of the occurrence of operating room (OR) fires have ranged from 217 to 650 events each year in the United States [3]. A study using the US Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience database noted 565 surgical fire events between the years 2000 to 2020 that resulted in patient or surgical personnel harm [4].

A 2018 study by the Pennsylvania Patient Safety Authority noted a decrease of 71 percent in OR fires since 2011 [5], which is consistent with other data [6,7]. However, since one-half of the states do not have mandatory reporting, the actual number is probably higher.

Most injury claims occur in an outpatient setting (78 percent), involve the upper body (85 percent), and are cases managed with monitored anesthetic care (MAC; 76 percent) [8].

●Impact – Patient injuries after an OR fire are often severe (eg, painful and disfiguring burns to the face and neck or severe airway injury with tracheostomy and permanent lung damage) [8]. Typically, a surviving patient must undergo several surgeries to treat acute burn injuries and revise scar tissue, causing recurring anxiety, post-traumatic stress, and economic burden [8,9].

All members of the surgical team involved in an OR fire are typically implicated in some degree of negligence and culpability. Examination of closed claims data shows that a payment was made in 78 percent of the claims [8]. Median settlement value was approximately USD $120,000. One case in Washington state awarded USD $30 million to a patient with severe injuries from an airway fire; the anesthesiologist, surgeon, and hospital each paid multimillion dollar judgments [10].

In rare cases, a member of the surgical team may sustain burns to their hands. However, most OR fires are limited in scope and involve only the patient. Also, the fire almost never gets hot enough to activate the OR sprinkler system or damage any equipment.

CAUSES: THE FIRE TRIAD — 

The combination of an oxidizer (eg, oxygen [O₂], nitrous oxide [N₂O]), a fuel (eg, alcohol-based prep solutions, surgical towels, drapes), and an ignition source (eg, electrosurgery unit [ESU], laser) in a closed environment can result in the eruption of flames. Strategies to prevent and extinguish fires are based on separating and/or controlling these three elements of the "fire triad" (picture 1) [11,12].

Although each element of the fire triad is typically managed by an individual member of the surgical team (eg, the anesthesiologist, surgeon, or nursing staff), overall awareness of fire risks is the shared responsibility of all team members. (See 'Risk-based approach to fire prevention' below.)

Oxidizers — The most common oxidizers in an OR are O₂ and N₂O, which are typically controlled by the anesthesia providers [8].

A distinction should be made between substances that are classified as oxidizers versus those that are flammable or combustible. O₂ and N₂O are not flammable gases like hydrogen or methane. Oxidizers are not fuels and are not consumed in a fire, but act to accelerate the burning process. A fire is more likely to erupt if fuels are present in an environment with a high concentration of an oxidizer (ie, O₂ or N₂O) compared with room air.

Oxygen — O₂ was the oxidizer in 95 percent of fires in the American Society of Anesthesiologists (ASA) Closed Claims Database [8]. It is not surprising that open delivery of O₂ from a direct source, through a device such as a nasal cannula or face mask, is the major factor contributing to most OR fires [8,13-19]. Even room air can support combustion and fire, although this risk is lower at its oxygen concentration of 21 percent [20]. At concentrations near 50 percent or higher, any spark or generated heat can ignite a fuel source [21]. Even at O₂ concentrations above 30 percent, the burning process is accelerated [21,22]. Studies have demonstrated that as O₂ concentration is increased from 21 to 50 percent, the time required for surgical drapes to ignite decreased while the burn rate increased [22,23].

During laparoscopy, gas line connection errors that result in insufflation of the abdomen with O₂ rather than carbon dioxide have resulted in intra-abdominal fires [24,25].

Nitrous oxide — N₂O is an oxidizer, with virtually the same oxidizing potential as O₂. Therefore, administering a mixture of 50 percent oxygen and 50 percent N₂O is the same as giving 100 percent oxygen [26,27].

Fuels — Multiple fuel sources may be found in all ORs and procedure areas (table 1).

Alcohol-based prep solutions — Alcohol-based surgical prep solutions (eg, ChloraPrep, DuraPrep, and Prevail-FX) contain approximately 70 to 75% isopropyl alcohol and serve as excellent fuels (picture 2). Therefore, it is extremely important that these solutions be allowed to dry for at least three minutes before use of an ignition source such as the ESU or laser [19,28-37]. Preferably the prep solution should be completely dry before draping. Even after three minutes, a fire occurred in more than one-quarter of simulated cases if there was pooling of the alcohol-based prep solution [37]. Notably, alcohol-based fires may not be immediately recognized since the flame is nearly invisible [38,39].

By contrast, povidone-iodine solutions (eg, Betadine) and chlorhexidine soaps (eg, Hibiclens) are not flammable and do not require a set drying time before the use of an ignition source. (See "Overview of control measures for prevention of surgical site infection in adults", section on 'Skin antisepsis'.)

Surgical drapes, towels, sponges, and gauzes — Surgical drapes, towels, sponges, and gauzes are manufactured from cotton, paper, or plastics ― all of these are excellent fuels (picture 3). When O₂ levels exceed 50 percent, O₂ becomes trapped within the fine fibers and naps of cotton towels or drapes. This O₂ can vigorously promote combustion, a phenomenon known as "surface fiber flame propagation" [40].

Endotracheal tubes, laryngeal masks — Endotracheal tubes and laryngeal mask airways are fuel sources because they are made from either silicone or polyvinyl chloride, which will burn readily (picture 4).

Organic matter — Hair can ignite, especially if coated with wet alcohol (picture 3). Similar to cotton materials, fine body hair can trap O₂, resulting in a fiber flame propagation phenomenon. (See 'Surgical drapes, towels, sponges, and gauzes' above.)

Bowel gas can ignite due to its composition of methane, hydrogen, and O₂. Patients who have used mannitol-based bowel preparations produce more gas than those who used polyethylene glycol or sodium sulfate preparations [11].

Ignition sources — An ignition source (ie, heat) is the remaining element in the fire triad. Although it is possible for flames to erupt when an ignition source comes into contact with a fuel in room air, the flame will be more intense and severe in an environment with an increased concentration of O₂ [13,29].

Most ignition sources are under the control of surgeons, including:

Electrosurgery unit (ESU) — The ESU is the most common ignition source in the OR [41], with the monopolar electrosurgical pencil, often referred to as the "Bovie," being the most common source of ignition. In the ASA Closed Claims Analysis, the ESU was found to be the ignition source in 90 percent of the cases [8].

Holding the ESU tip above the tissue or touching the tip to a hemostat poses the greatest risk, although any use can cause ignition (figure 1). Fire can be ignited by either the monopolar tip or loose or worn connectors and cables. Use of a bipolar ESU lowers the risk of spark or arcing. (See "Overview of electrosurgery".)

Surgical lasers — Laser use is often a factor in OR fires, particularly during airway surgery. High-power lasers can ignite any dry materials they contact including drapes, towels, and sponges. Many lasers use a fiber that can become broken or cracked, resulting in the escape of energy to nearby flammable materials. (See "Overview of electrosurgery", section on 'Laser'.)

Fiberoptic lights — Fiberoptic light sources can create very high temperatures focused on a specific spot. If not connected to an output device such as a headlamp or lighted instrument, these sources can burn a patient directly, or ignite or melt surgical drapes, resulting in a burn injury.

Other potential ignition sources — Other potential ignition sources include drills, coagulators, hot wire cautery, and defibrillators. Occasionally, a fire is caused by electrical problems in other OR equipment (eg, a short circuit or other faults) or by overloaded circuits.

Rarely, carbon dioxide-absorbent systems that have a strong alkali base (Baralyme or soda lime) have been implicated as the cause of anesthesia machine fires. The mechanism for this type of fire is an exothermic chemical reaction between sevoflurane and a desiccated CO₂ absorbent [42,43].

Notably, even in the absence of any obvious ignition source, a fire can ignite with only a static spark [44].

RISK-BASED APPROACH TO FIRE PREVENTION — 

Key elements to a risk-based approach to fire prevention in the OR are risk assessment, communication among members of the surgical team, and preventive measures based on level of risk.

One approach to fire prevention in the OR is similar to that used in the "Silverstein Fire Risk Assessment Tool" [45]. Other formal fire prevention tools include the approach published by the Anesthesia Patient Safety Foundation (APSF) (algorithm 1) [46], and an algorithm published by the American Society of Anesthesiologists (ASA) (algorithm 2) [29].

●Risk assessment – The "Silverstein Fire Risk Assessment Tool," [45] is easy to use and is supported by closed malpractice claims data [8]. Before surgery begins, risk is assessed, and one point is awarded for each of the following major risk factors:

•Use of an open oxygen (O₂) source (eg, delivery of O₂ via nasal cannula or face mask), a factor in 84 percent of claims.

•Presence of an ignition source (eg, electrosurgery unit [ESU] or laser), a factor in 90 percent of claims.

•Procedure site above the xiphoid process, a factor in 85 percent of claims. These procedures are when the surgery site is closer to an open supplemental O₂ source that may be administered to the patient. Examples of high-risk procedures include ear, nose, or throat (ENT) surgery, facial surgery such as blepharoplasty, thyroid surgery, and carotid endarterectomy.

•In our practice, we add the use of an alcohol-based prep as a fourth factor.

These risk points are summed to produce a fire risk score of 0 to 3 (or 0 to 4). Procedures are categorized as low-risk (score of 0 or 1), intermediate-risk (score of 2), or high-risk (score of 3 to 4). The plan for surgical fire prevention is based on the level of risk for the individual patient and procedure [45]. (See 'Risk prevention: High-risk procedures' below and 'Risk prevention: Intermediate- or low-risk procedures' below.)

●Communication – The most important preventive measure is communication among surgical team members regarding potential fire risk and plans to manage risks [29,47-50]. Failures in communication among surgical team members, focusing on other tasks with loss of vigilance for possible fire hazards, and the facility's failure to educate all OR staff regarding fire prevention strategies are factors cited in most legal claims for OR fires [8,47,48].

Specifically, team members (ie, anesthesiologist, surgeon, and nursing staff) must:

•Verbally verify identified fire risks.

•Discuss specific plans to minimize risk. (See 'Limit oxygen administration and avoid nitrous oxide' below and 'Manage fuels' below and 'Manage ignition sources' below.)

•Delegate specific team roles for preventing and managing a fire. (See 'Management of a fire' below.)

•Assess hazards continuously during surgery. Each surgical team member assesses hazards under his own control (eg, oxidizer, fuel, or ignition source hazards), as well as observes the actions of all other team members.

•Speak up immediately if any preventable risk or evidence of a possible fire is observed.

●Strategies to prevent and manage fires – Strategies to prevent and manage OR fires are discussed below. (See 'Risk prevention: High-risk procedures' below and 'Management of a fire' below.)

RISK PREVENTION: HIGH-RISK PROCEDURES — 

For high-risk procedures with a fire risk score of 3 or 4, strategies to eliminate or mitigate risk factors include the precautions outlined below (table 2).

Limit oxygen administration and avoid nitrous oxide — The most effective preventive measure is to eliminate the use of an open oxygen (O₂) source, or limit O₂ concentration to ≤30 percent, as well as avoid nitrous oxide (N₂O) [13-18].

Management of open oxygen delivery systems

Management strategies for procedure-related and patient-related risk factors include:

●Procedures at or above the xiphoid – Avoid open delivery of O₂ (eg, via a nasal cannula or face mask) whenever possible. Many healthy patients tolerate sedation without O₂ supplementation during monitored anesthesia care (MAC) [51].

●Patients requiring oxygen supplementation – For patients who require O₂ supplementation to avoid hypoxia, use an O₂ blender or an adaptor to the common gas outlet of the anesthesia workstation to deliver an O₂ concentration ≤30 percent via an open system. Key points include the following:

•The delivered O₂ concentration must be continuously monitored using an O₂ analyzer, and adequacy of oxygenation is continuously monitored with pulse oximetry. If the patient remains hypoxic at an O₂ concentration ≤30 percent, then fraction of inspired O₂ (FiO₂) is increased to the minimum level required to maintain adequate hemoglobin O₂ saturation as measured by pulse oximetry (SpO₂), typically ≥90 to 95 percent. However, the anesthesia provider must realize that if delivered O₂ concentration is >30 percent, fire risk is increased. In such cases, converting to a closed O₂ deliver system (eg, endotracheal tube [ETT] or supraglottic airway [SGA] device) should be considered.

•No supplemental O₂ should be delivered from a 100 percent O₂ source, such as a free-standing O₂ outlet, the supplemental O₂ flowmeter on the anesthesia workstation, or an O₂ tank. If the anesthesia machine does not have a common gas outlet, adjustment of O₂ concentration during open delivery of O₂ via a nasal cannula or face mask can be accomplished using the standard breathing circuit with an adaptor (picture 5). The adjustable pressure-limiting valve or pop-off valve must be closed when this technique is used. Notably, many newer anesthesia machines have the ability to blend the oxygen concentration delivered via the supplemental gas flowmeter or via a separate air flowmeter in addition to the oxygen flowmeter.

•High-flow nasal O₂ use for a patient undergoing MAC anesthesia presents an extreme risk for OR fire. These devices can deliver up to 100 L/minute of 100 percent oxygen [52]. Thus, the clinician must take measures to mitigate this risk, typically by decreasing F_iO₂ to <30 percent from this high flow source of O₂.

Additional risk mitigation strategies include:

•Reducing oxygen concentration before ignition source activation – Before activation of any ignition source in a patient receiving O₂ via an open delivery system, the surgeon must notify the anesthesiologist to ensure that the O₂ concentration has been reduced to ≤30 percent. Generally, three to five minutes is required to allow dissipation of the O₂ concentration on the surgical field [29]. Although reduction of the O₂-enriched atmosphere to a safe level (≤30 percent) may require as little as 90 seconds if no surgical drapes are used, O₂ may remain trapped in the pockets of any surgical towels or drapes. Thus, several minutes are necessary to ensure safe dissipation of the trapped O₂ [14].

•Conversion to a closed oxygen delivery system – If adequate O₂ saturation (ie, SpO₂ ≥95 percent) cannot be maintained with an O₂ concentration of ≤30 percent, secure the airway with an ETT or SGA to provide a closed O₂ delivery system, then adjust the F_iO₂ to the minimum O₂ concentration required to avoid hypoxia. For example, patients with obesity and obstructive sleep apnea may have mechanical obstruction of the airway with snoring and periods of rapid desaturation if they are sedated during MAC. In such cases, it is preferable to control the airway with an ETT or SGA to eliminate mechanical obstruction and desaturation rather than using an open system to deliver an O₂ concentration >30 percent (algorithm 1) [29,46,53,54].

Avoid nitrous oxide — Avoid administration of N₂O for high-risk procedures and settings.

Special precautions during airway surgery — Airway surgical procedures have the highest airway fire risk score (ie, 3 points) on assessments such as the “Silverstein Fire Risk Assessment Tool” [45]. Strategies specific for prevention of fire in the airway or other sites during airway surgery include:

●Establish a fire risk reduction plan – Ensure that a preoperative team discussion of a fire risk reduction plan is included in the surgical briefing [29] (see "Patient safety in the operating room", section on 'Timeouts, briefing, and debriefing'). This includes discussion of O₂ concentration and ignition sources.

●Manage ignition sources

•Designate a laser safety officer who has an explicit role of safety oversight to ensure use of a reduced FiO₂, proper eyewear, laser-resistant endotracheal tubes (ETTs) that are specific to the type of laser being used, proper plume management, and other safety measures. (See "Basic principles of medical lasers", section on 'Laser principles'.)

•Call a timeout prior to opening the trachea so that the surgeon, nurses, and anesthesiologist can verify that all electrosurgery units (ESUs) have been handed off the surgical field. Then the FiO₂ is increased to 100 percent prior to manipulation of the ETT (but only after the ESU is no longer on the surgical field).

●Manage oxygen or nitrous oxide concentration

•For an intubated patient, reduce the O₂ concentration to ≤30 percent, or to the minimum level required to avoid hypoxia, and discontinue use of N₂O (see 'Avoid nitrous oxide' above) when the surgeon gives notice for activation of any ignition source.

•For a patient with a face mask or nasal tubing, ensure that low O₂ concentration is precisely delivered by attaching the face mask or nasal tubing to a 3 or 4 mm ETT connector, which is attached to the Y-piece of the breathing circuit of the anesthesia machine so that a preset blended O₂ and air concentration with FiO₂ <30 percent can be delivered (the lower the better). Alternatively, several newer anesthesia machines can deliver an analyzed, blended air/O₂ mixture from the auxiliary gas outlet.

•For a patient receiving transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) technique for laryngeal surgery, which provides effective oxygenation to the apneic patient for up to 60 minutes, delivered O₂ concentration should be reduced to 30 percent once suspension laryngoscopy has been achieved and prior to initiating laser surgery. One study has shown that tracheal O₂ concentration falls to 30 percent within 8 to 10 seconds of reduction of high flow gas mixture [55].

•When using an auxiliary gas outlet, the delivered O₂ must be diluted with medical air to decrease the O₂ concentration. In order to decrease the FiO₂ to 0.30, 1 L of O₂ is mixed with 7 L of medical air.

•Since the O₂ sensor does not recognize the bound O₂ of the N₂O, administration of N₂O reduces measured FiO₂. However, N₂O supports combustion similarly to O₂ and is never an appropriate diluent for O₂.

•Adequate notice (at least three to five minutes) is required to allow both the fraction of inspired O₂ (FiO₂) and the fraction of expired O₂ (FeO₂) to be reduced to a safe level (ie, ≤30 percent). Control of both FiO₂ and FeO₂ in a closed delivery system depends upon the total medical gas flow (air only, or an air: O₂ mixture). In one study, the reduction of FeO₂ from 60 to 30 percent required 100 seconds with a total gas flow rate of 5 L/minute, but four minutes were required with a flow rate of only 2 L/minute [56]. The anesthesiologists and surgeon must realize that dilution of both FiO₂ and FeO₂ to ≤30 percent does not occur instantly.

•Monitor the O₂ analyzer to ensure that FiO₂ is <30 percent in the actual delivered O₂ concentration, and the FeO₂ goal of <30 percent is met. We never simply reduce flow of 100 percent O₂ delivered through an open source such as a facemask or nasal cannula, as this will result in nonhomogeneous zones of O₂ concentrations and is also a dangerous fire risk.

•Minimize O₂ buildup by configuring the surgical drapes around the airway to be "open" to prevent accumulation of O₂ underneath them, flushing the surgical field with medical air, and scavenging the operating field with a suctioning device when an ESU is being used to minimize buildup of supplemental O₂ and/or N₂O [29].

●Use a fire-resistant ETT. For procedures with planned laser use inside or near the airway in an intubated patient, use a cuffed laser-resistant ETT regardless of the O₂ concentration [29,57-67]. Key points include the following:

•The selected ETT must be resistant to the particular laser that will be used.

•Fill the cuff of the ETT with saline colored with an indicator dye such as methylene blue, which acts as a marker if the cuff is perforated by the laser.

●Anesthetizing a patient for a tracheostomy presents unique challenges because these patients are typically intubated and require high inspired O₂ concentrations to maintain adequate oxygenation such that decreasing the FiO₂ may not be possible [68,69]. Therefore, it is critical that the anesthesiologist ensures that the surgeon does not use the ESU during entry into the trachea. The ESU may be used to create the skin incision, but when entering the trachea and to create the tracheal flap, a scalpel or scissors alone should be used. Hemostats and sutures can be used to control any bleeding. (See "Anesthesia for tracheostomy".)

Manage fuels — Nurses and other hospital staff typically control fuels in the OR (eg, surgical drapes, towels, sponges, and gauzes, as well as alcohol-based prep solutions) (picture 1). The following principles apply to all procedures and settings. Actions performed by the nursing staff include the following:

Alcohol-based prep solutions

●Apply alcohol-based prep solutions using an appropriately sized, single-use applicator. Large applicators (eg, a 26 mL size) should never be used in a case involving the head or neck. Use of larger applicators for small anatomical areas such as the head or neck will result in accumulation of too much fuel, with pooling onto surgical towels and drapes.

●Allow adequate drying time for alcohol-based prep solutions before applying surgical drapes. Most solutions have a minimum drying time of three minutes, but this time increases when the prep solution is applied to areas of the body that are hairy or in areas containing skin folds and body creases [19,29-36]. Prepped skin can be tested for dryness with dry sterile gauze prior to initiating electrocautery.

●After adequate drying time, assess for evidence of pooling of excess prep solution prior to draping the patient [37]. Many surgical fires have occurred in emergency cases, where drying times were not strictly observed and an ignition source was used near a draped area still covered with wet alcohol-based prep solution [8,19,70].

●Remove any flammable liquid-soaked materials from the patient care vicinity prior to draping or use of electrosurgery, cautery, or a laser, as recommended by the National Fire Protection Association (NFPA)-99 (ie, the Health Care Facilities Code) [71].

Drapes, towels, sponges, and gauzes

●Configure surgical drapes to minimize the accumulation of oxidizers (eg, O₂) under the drapes.

●Moisten sponges and towels if used in a surgical field near an ignition source, particularly when used in or near the airway.

●Have sterile water or saline available for fire suppression. For procedures in the oral cavity, keep a syringe full of saline available.

●Keep excess drapes and towels in an area far removed from ignition sources.

Endotracheal tubes — The endotracheal tube (ETT) can be a fuel source and is easily ignited by a laser or ESU if the surgeon is operating in or around the airway. In such cases, the anesthesiologist should use an ETT that is laser- and fire-resistant. The tube should have a dual cuff, and both cuffs should be filled with saline that is colored with methylene blue. Also, the anesthesiologist should use the lowest possible FiO₂ that the patient can tolerate. (See 'Special precautions during airway surgery' above.)

Notably, many "laser-resistant," ETTs are only safe to use with a specific type of laser. Therefore, the anesthesiologist must ensure that the tube being used is specifically resistant to the laser that the surgeon is using.

Organic material — Scavenge the surgical field to remove ignitable organic material (eg, hair or material on the Bovie tip) before and during use of an ignition source.

Manage ignition sources — Surgeons typically control ignition sources (ie, ESU or laser) (picture 1).

●In high-risk procedures and settings, the surgeon may elect to:

•Avoid ESU use altogether when possible.

•Use an alternative to a monopolar ESU that does not create sparks (eg, bipolar-tip ESU, harmonic scalpel) [41]. (See "Overview of electrosurgery".)

●If an ignition source is to be used in a high-risk procedure, bipolar is safer than monopolar ESU as it can significantly reduce sparking. However, a fire can be started with a bipolar ESU; thus, it should never be considered completely “safe”. In all cases, the surgeon should:

•Give the anesthesiologist adequate notice (three to five minutes) before activating the ESU or other ignition source so that the O₂ concentration can be reduced to ≤30 percent and N₂O can be discontinued. (See 'Limit oxygen administration and avoid nitrous oxide' above.)

•Use the lowest effective setting once the ESU is activated. (See "Overview of electrosurgery".)

•Protect heat sources (ie, keep the active electrode tip of the electrosurgical unit [ESU] in a holster when not in use).

RISK PREVENTION: INTERMEDIATE- OR LOW-RISK PROCEDURES

Low-risk procedures — For all procedures, including those with a low fire risk score of 0 or 1, follow the standard fire safety precautions. Specific recommendations include (table 3):

●If an open oxygen (O₂) source is used, limit O₂ concentration to ≤30 percent.

●Allow prep solutions to dry for at least three minutes prior to draping.

●Configure surgical drapes to minimize the accumulation of O₂ under the drapes.

●Protect heat sources (eg, keep the active electrode tip of the electrosurgical unit [ESU] in a holster, switch the laser to standby when not in use).

Intermediate-risk procedures — Procedures with an intermediate fire risk score of 2 have the potential to suddenly convert to being high-risk procedures. Standard fire safety precautions should be followed in these cases (see 'Low-risk procedures' above). However, the surgical team must be prepared to immediately initiate high-risk precautions if the procedure becomes high-risk (eg, imminent delivery of O₂ from an open source due to inability to maintain adequate patient oxygenation on room air). (See 'Risk prevention: High-risk procedures' above.)

Examples of intermediate-risk procedures include:

●Ignition source and procedure remote from an open O₂ source. (In contrast, if an ignition source is used in proximity to open delivery of O₂, then the risk level would be elevated).

●Procedure that is at or above the xiphoid process, but no supplemental O₂ is administered, or a closed O₂ delivery system is used. (In contrast, if a case is at or above the xiphoid level, with open delivery of O₂, then the risk level would be elevated).

●Procedure that is at or above the xiphoid process near an open source of O₂, but no ignition source is used. However, a fire ignited by a static spark is always a possibility [44]. (In contrast, if a case is cranial to the xiphoid level with open delivery of O₂ and an ignition source is used in the surgical field, then the risk level would be elevated).

MANAGEMENT OF A FIRE — 

The earliest warnings of a fire include smelling smoke, hearing a pop, or seeing a flash. The surgical procedure should be halted immediately, or as soon as it is safe to do so, while the possibility of fire is investigated. If confirmed, all efforts are directed toward stopping the burning process and removing both the fuel and oxidizer as well as all burning materials [72]. An excellent approach to fire management has been published by the American Society of Anesthesiologists (ASA) (algorithm 2) [29].

Fire on the patient — Surgical team members should perform their preassigned fire management tasks as quickly as possible, including:

●Stop the flow of all airway gases.

●Pour water or saline on any hot spots during the first attempt to extinguish the fire.

●Remove all drapes and burning material from the patient and throw the drapes on the floor. Even if the fire seems to be extinguished, an assessment must be made for smoldering elements and flames that may be hidden underneath the drapes without evidence on the surface (eg, smoldering embers, melted plastic, and burning fuels).

●Extinguish small fires by patting with towels or sponges, preferably wet ones.

●Use a fire extinguisher if a fire is not immediately extinguished after the first attempt.

●Initiate the RACE fire protocol if a fire persists despite the efforts listed above:

•Rescue – Remove the patient from the burning source.

•Alarm – Activate the fire alarm system.

•Confine – Close doors to the OR after evacuation. Turn off medical gas supply lines.

•Extinguish – Use a fire extinguisher as you retreat from the area.

Emergency evacuation guidelines for use in the operating room or intensive care unit have been published [73].

Fire in the airway — Management of a suspected fire in the airway includes:

●Remove the endotracheal tube (ETT) immediately and simultaneously stop the flow of airway gases. The precise sequence of these two tasks is not as important as accomplishing both immediately.

●Pour water or saline into the patient's airway to extinguish any residual burning materials after the ETT is removed and all gases have been shut off (eg, O₂, nitrous oxide [N₂O], and/or medical air).

●Reestablish ventilation, preferably without the use of either O₂ or N₂O after the fire is extinguished.

●Assess the upper and lower airway as soon as possible. This includes direct visualization of the upper airway with laryngoscopy to look for melted plastic ETT fragments and soft tissue swelling, which could lead to imminent airway compromise. The lower conducting airways are assessed with bronchoscopy to look for soot and smoke residue, or other evidence of injury or inflammation caused by inhalation of toxic smoke or superheated gas or steam (picture 4). (See "Inhalation injury from heat, smoke, or chemical irritants".)

Subsequent patient management — After rescue of the patient, further management includes:

●Perform a thorough assessment for burn injuries, including the entire posterior as well as anterior body surface areas. (See "Emergency care of moderate and severe thermal burns in adults".)

●The injured areas should be cooled with moistened sterile saline or sterile water dressings. Initially, no ointments or salves should be applied. A burn specialist should be consulted for further treatment recommendations. (See "Emergency care of moderate and severe thermal burns in adults", section on 'Immediate burn care and cooling'.)

●Assess the airway if an airway fire or a fire around the patient's face or neck has occurred. (See 'Fire in the airway' above.)

●Assess the patient and all personnel who were in the OR for smoke inhalation. Many plastic products can give off toxic byproducts, such as cyanide and phosgene, in addition to carbon monoxide. Initial evaluations may be normal in patients with inhalation injury who subsequently develop severe respiratory distress. (See "Anesthesia for patients with acute burn injuries", section on 'Assess for pulmonary abnormalities' and "Inhalation injury from heat, smoke, or chemical irritants".)

●Transfer patients who meet the American Burn Association's criteria (table 4) to a burn center. (See "Emergency care of moderate and severe thermal burns in adults", section on 'Disposition'.)

INSTITUTIONAL RESPONSIBILITIES — 

Fires in the OR are prevented by increasing awareness of risks among OR personnel and changes in clinical practice to reduce risks. Institutional responsibilities include the following (table 5):

●Risk assessment – Stratification of risks is based on utilization as well as physical location of a procedure area. To illustrate, an OR used solely for eye examinations under anesthesia, where control of bleeding is unlikely and no ignition sources would ever be used has a lower risk than a procedure room in a remote location that might be used for some interventions with fire risk factors. The most current National Fire Protection Association (NFPA) 99 Health Care Facilities Code stratifies risk for activities, equipment, and preventive measures in facilities according to potential outcomes that would result from system failures:

•Category 1 – If failure occurs, major injury or death to patients, staff, or visitors is likely.

•Category 2 – If failure occurs, minor injury to patients, staff, or visitors is likely.

•Category 3 – If failure occurs, injuries are not likely, but minor discomfort to patients, staff, or visitors is likely.

•Category 4 – If failure occurs, no impact to patients, staff, or visitors would occur.

Since category 1 is the default and has the most stringent requirements, no formal assessment is needed. However, a formal assessment by a multidisciplinary team of engineers, clinical personnel, and other stakeholders should take place if a facility requests a code designation of category 2, 3, or 4 for a specific location. Such a risk assessment is useful for a facility using certain locations for types of procedures that may not need the systems and redundancies in a Category 1 OR [74].

●Education – All persons working in the surgical environment should receive training regarding OR fire prevention and management. The educational content should be specific to the OR, rather than a generic fire safety course [72]. Issues that are typically covered include the need for excellent communication, hazards regarding oxygen (O₂) use and the electrosurgery unit (ESU), proper use of fire extinguishers, and evacuation of an anesthetized patient.

●Fire drills – Periodic fire drills should be held in the OR, with surgeons, anesthesiologists, and nursing staff all involved, as well as the hospital's fire marshall. Drills allow participants to practice in-place defense strategies, as well as horizontal and vertical evacuation of anesthetized patients. Participants also become familiar with the locations and operation of the nearest fire extinguishers and shut-off valves for piped medical gases.

Typically, drills are conducted outside of normal operating hours during dedicated educational time, and surgical team members from all shifts are accommodated. One large OR suite may be used to conduct the drill, with videotaping for later review. Ideally, the exercise includes a debriefing to identify areas that need improvement, and to praise appropriate responses.

●Availability of appropriate fire extinguishers – Extinguishers for use in the OR should be safe for external and internal patient exposure, and also safe for OR personnel. Practice with using an extinguisher (or an extinguisher simulator) during a drill can be helpful in providing familiarity with the type of extinguisher provided by the institution.

Fire extinguishers are classified according to the agent used (table 6) [75].

•Carbon dioxide (CO₂) extinguisher – CO₂ is not toxic, readily dissipates, and is not likely to result in thermal injury; thus, the extinguishers available in the OR are usually CO₂ extinguishers. This is the preferred extinguisher for the OR, and it is recommended by American Society of Anesthesiologists (ASA) and Emergency Care Research Institute (ECRI).

•FE-36 extinguisher – The FE-36 extinguisher uses an agent that may be as safe and effective as CO₂, but it is more expensive, and may result in sensitization of the myocardium to catecholamines to a minor extent if direct contact with the heart or blood vessels occurs (eg, during open surgical procedures).

•Water mist AC-rated extinguishers – Water mist extinguishers are effective, but more time is required to extinguish a fire with water compared with CO₂. Also, the user should consider that water-based extinguishers are large, heavy (approximately 30 pounds), and difficult to manage because they contain enough water volume to allow multiple attempts to extinguish a fire.

•Dry chemical extinguishers – Dry chemical fire extinguishers are avoided not only because they are unsafe for internal exposure, but they are also associated with health concerns for OR personnel (table 6). For example, dry chemical dust can cause respiratory irritation, and is difficult to remove from moist tissues and membranes. Also, although ABC dry chemical extinguishers are the most effective fire suppressants for all types of fire, all equipment (devices and products) in the OR would typically be destroyed by these chemicals.

•Halon extinguishers – Halon extinguishers are sensitize the myocardium to catecholamines, and this may result in lethal cardiac arrhythmias (table 6) [76,77].

RESOURCES AND GUIDELINES — 

An outline of resources is provided for further details regarding education of OR personnel in the causes and prevention of OR fires.

Professional Societies

●American Society of Anesthesiologists – The American Society of Anesthesiologists (ASA) has published and updated a practice advisory for the prevention and management of OR fires, which includes an algorithm (algorithm 2) [29,53] (see 'Risk-based approach to fire prevention' above). The advisory also contains the following suggestions for reduction of fire risks by anesthesiologists:

•Obtain education specific to the prevention and management of OR fires.

•Perform OR fire drills, which should be practiced periodically with all surgical staff.

•Assess fire risk and assign specific tasks to be carried out by each team member.

•Prevent surgical fires by reducing factors contributing to high-risk environments.

•In the event of an OR fire, emphasize preassigned tasks, and de-emphasize the specific order for these tasks.

●Anesthesia Patient Safety Foundation – The Anesthesia Patient Safety Foundation (APSF) has published an algorithm (algorithm 1) [46,78] and released "Fire Safety Video: Prevention and Management of Operating Room Fires" [54,79] (see 'Risk-based approach to fire prevention' above). Created with guidance from the Emergency Care Research Institute (ECRI), the 18 minute video may be downloaded without cost from the APSF website [79].

●Association of Perioperative Registered Nurses – The Association of Perioperative Registered Nurses (AORN) has developed a fire safety "toolkit," for use by its members and others [80]. The toolkit includes various fire risk assessment tools, a planning guide for OR fire drills, and educational resources (eg, posters, slide shows).

●Society of American Gastrointestinal and Endoscopic Surgeons – The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) developed a formal program for the safe use of electrosurgical unit (ESU) devices, including education in the prevention of surgical fires [81]. This Fundamental Use of Surgical Energy (FUSE) training program includes a manual and an online multimedia curriculum available from SAGES free of charge [82]. The FUSE online curriculum includes:

•Fundamentals of electrosurgery

•Mechanisms and prevention of adverse events with electrosurgery

•Monopolar devices

•Bipolar devices

•Radiofrequency for soft tissue ablation

•Endoscopic devices

•Ultrasonic energy devices

•Microwave energy systems

•Energy-based devices in pediatric surgery

•Integration of energy systems with other devices

A certification exam is available for a fee after FUSE training.

●National Fire Protection Association – The National Fire Protection Association (NFPA) is the primary originator of fire codes and standards in the United States, and sponsors the annual national "Fire Prevention Week," event [83]. Although not an enforcement agency, the NFPA has achieved consensus regarding fire safety across national and international boundaries. Examples of NFPA codes that affect all hospitals and health care workers include the "NFPA 99: Health Care Facilities Code," and "NFPA 101: Life Safety Code" [84,85].

Regulatory agencies

●US Food and Drug Administration (FDA) – In 2010, the FDA created the Preventing Surgical Fires Initiative (PSFI) to coordinate efforts to disseminate and apply available knowledge regarding fire prevention [86]. In 2015, the administration of the PSFI was transferred from the FDA to the Joint Commission (JC). The FDA has also issued a recommendation letter outlining how fires in the OR occur, recommendations on steps to avoid a fire, and what to do in the event of a fire [87]. If an OR fire occurs, it should be reported to the FDA through their voluntary reporting system, the MedWatch FDA Safety Information and Adverse Event Reporting program, which may be accessed from the FDA website.

●The Joint Commission (JC) – As the largest accrediting agency for health care facilities, the JC has an interest in prevention of surgical fires. In 2003, the JC issued "Sentinel Alert 29," after receiving reports of two surgical fires [88]. The alert summarizes prior recommendations of the ECRI, and gives a brief overview of fire prevention strategy. Specific JC standards include the following:

•Environment of care (EC) standard EC.02.03.01 requires that organizations manage fire risks [89].

•EC standard EC.02.03.03 mandates fire drills [90].

•EC standard EC.04.01.01 stipulates that practitioners collect information to monitor conditions in the environment at least annually, by performing assessments for new hazards and reviewing emergency plans for objectives, scope, performance, and effectiveness [91].

Also, the JC has issued patient safety goals for ambulatory surgery centers, including the need for specific education to prevent and manage OR fires, and guidelines to minimize use of open delivery of O₂ [92].

SOCIETY GUIDELINE LINKS — 

Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Patient safety in the operating room".)

SUMMARY AND RECOMMENDATIONS

●Incidence and impact – Most operating room (OR) fires in the United States (217 to 650 events annually) occur during monitored anesthetic care (MAC) during an outpatient procedure involving the upper body. Patient injuries after an OR fire are often severe (eg, painful and disfiguring burns). (See 'Incidence and impact of operating room fires' above.)

●Causes – The "fire triad," is a combination of an oxidizer (eg, oxygen [O₂], nitrous oxide [N₂O]), a fuel (eg, alcohol-based prep solutions, surgical towels, drapes, sponges, and gauzes, as well as alcohol-based prep solutions), and an ignition source (eg, electrosurgery unit [ESU], laser, fiberoptic lights) in a closed environment, which can result in OR fires (picture 1). High-risk procedures have four factors: an open O₂ source (eg, delivery of O₂ via nasal cannula or face mask), an ignition source (eg, ESU or laser), surgery at or above the level of the xiphoid process, and an alcohol based prep. (See 'Causes: The fire triad' above.)

●Approach to prevention – Key elements to a risk-based approach to OR fire prevention are risk assessment, communication among surgical team members of potential risk and management plans, and specific prevention strategies. (See 'Risk-based approach to fire prevention' above.)

●Risk prevention for high-risk procedures – For procedures with a high fire risk, strategies to eliminate or mitigate risk factors include (table 2) (see 'Risk prevention: High-risk procedures' above):

•Limit O₂ administration and concentration (see 'Oxygen' above and 'Limit oxygen administration and avoid nitrous oxide' above)

•Avoid N₂O (see 'Nitrous oxide' above and 'Avoid nitrous oxide' above)

•Special precautions during airway surgery (see 'Special precautions during airway surgery' above):

•Manage fuels (see 'Fuels' above and 'Manage fuels' above)

•Manage ignition sources (see 'Ignition sources' above and 'Manage ignition sources' above)

●Risk prevention for intermediate- or low-risk procedures – Standard fire safety precautions are followed for procedures at any body site (table 3). (See 'Risk prevention: Intermediate- or low-risk procedures' above.)

●Management of an OR fire (algorithm 2 and table 7):

•Fire on the patient (see 'Fire on the patient' above)

•Fire in the airway (see 'Fire in the airway' above)

•Subsequent patient management (see 'Subsequent patient management' above)

●Institutional responsibilities (see 'Institutional responsibilities' above)

ACKNOWLEDGMENT — 

The UpToDate editorial staff acknowledges Charles E Cowles, Jr, MD, MBA (deceased), who contributed to earlier versions of this topic review.