An operating room fire is any fire that ignites in the operating or procedure room.
Anesthesia providers should be aware of the treatment and prevention of surgical and airway fires.
Surgical fires are defined as those that occur on or around a patient.
Airway fires are defined as surgical fires that ignite within the patient's airway or breathing circuit.
All fires require the triad of an ignition, oxidizer, and fuel. Thus, prevention in high-risk scenarios should aim at reducing or eliminating one of these elements.
Epidemiology
Incidence
Difficult to accurately assess because there is no FDA mandate requiring operating room staff to report a fire
In the US, there are approximately 550–650 surgical fires per year.
21% of surgical fires involve the airway.
Morbidity
Disfiguring or disabling injuries from operating room fires is estimated to occur in 20–30 patients per year (1).
Mortality
Death from operating room fires occur in ~1–2 patients per year (mostly airway fires)
Oxidizers (gases that can support combustion): Oxygen and nitrous oxide
Fuel: Alcohol-based surgical preps, ETT, breathing circuits, drapes, body hair, nasal cannula, face masks, intestinal gases
High-risk surgical procedures are defined as anytime an ignition source may come in close proximity to an oxygen-rich environment.
Procedures above the xiphoid, sedation with open oxygen source (face mask, nasal cannula)
Cataract
Carotid endarterectomy (cervical block)
Removal of skin lesions
Face lifts
Blepharoplasty
Procedures that "enter" the airway
Tracheostomy
Biopsy (vocal cords, tracheal)
Removal of lesions
Oropharyngeal procedures
Physiology/Pathophysiology
Oxygen lowers the temperature at which a fuel will ignite.
Even materials that will not burn in room air will do so in an oxygen-enriched environment.
Oxygen-enriched fires are hotter, more intense, and spread more rapidly.
Oxygen-enriched environments are defined as any atmosphere in which the oxygen concentration is >21% or the partial pressure is >160 mm Hg (2).
Drapes promote trapping or pooling of oxygen from open sources (blow by, face mask, nasal canula).
Airway procedures enter an enclosed, oxygen-enriched environment
Nitrous oxide supports combustion by dissociating and releasing heat and oxygen.
Prevantative Measures
Most, if not all, operating room, surgical, and airway fires are preventable.
Deliver safe room air sedation.
Select patients with normal pulmonary function
Judiciously administer hypnotics, sedative, and opioids
Use of a pulse oximeter and end-tidal CO2 to monitor the patient's oxygenation and ventilation can decrease hypoxic events by allowing earlier diagnosis of hypoventilation.
Oxygen saturations of 92% can be safe and acceptable; <90% is undesirable because the steep portion of the oxyhemoglobin dissociation curve puts the patient at risk for rapid desaturation.
Maintain supplemental oxygen <30% when administered via an open oxygen source in any head or neck surgery (3) [C].
Nasal cannula can be used at flow rates <4 L/minute if ignition sources are >10 cm from the oxygen outlet and the head is not draped (2) [C].
Venturi masks entrain room air to lower the FiO2 that is delivered.
"Blow by" with a hose is used when masks are not appropriate to the clinical situation. The use of a color adapter may be helpful to indicate the FiO2 that is delivered. Confirm that the device is properly sampling the area exposed to the ignition source.
Air–oxygen blenders are devices that mix medical air and oxygen into a gas source ranging from 21% to 100% oxygen. They are precise and reliable, but not always readily available in the operating room.
In-line oxygen sampling can be utilized to provide a more controlled oxygen delivery system. The connector of a 5.0 ETT can be attached to the Y- piece of a circuit, and the nasal cannula or face mask can then be connected to it. The pop-off valve needs to be closed completely and fresh gas flows (oxygen and air) can be adjusted accordingly. Be careful not to deliver nitrous oxide.
Adherent tape may be used to isolate the incision from the oxygen-enriched atmosphere.
Maintain a low threshold to convert to general anesthesia if the patient cannot maintain an oxygen saturation >92% with an FiO2 <30%, rather than just increasing the FiO2. An ETT or supraglottic device will confine enriched oxygen to the breathing circuit and lungs of the patient.
Drapes should not be placed until all flammable preps have dried fully.
Coating hair and facial hair with water-soluble surgical lubricating jelly renders the hair nonflammable.
Bipolar instead of monopolar electrocautery should be encouraged in high-risk surgeries. Bipolar devices create little or no sparking and have not been recorded to start any surgical fires.
Procedures that enter the airway or involve oropharyngeal tissue. Fires may be reduced by:
Placing moistened sponges around tissue and the endotracheal tube.
Using a laser-proof ETT. Polyvinyl chloride tubes can be readily penetrated by a laser to release oxygen within the lumen; additionally, they can burn in oxygen concentrations as low as 25%. Thus, they are considered the least safe option (4) [C].
Decreasing the FiO2 for 2 minutes prior to entering the airway and flushing air at 5–10 L/min to wash out excess oxygen.
Encouraging surgeons to enter the airway with a scalpel instead of electrosurgery (5) [C].
Avoiding nitrous oxide.
Diagnosis⬆⬇
Usually obvious with the presence of flames or smoke
Unusual noise or feeling of warmth
Treatment⬆⬇
In the event of a surgical fire:
Remove burning material from the patient. Discontinue the flow of all airway gases.
Have another member of the team extinguish the flame.
Assess the patient's injuries and treat as necessary.
Control any bleeding.
Evacuate the patient if there is danger from the smoke or fire.
Use an aqueous solution to extinguish non-electrical fires.
However, the fluid resistance of surgical drapes may not allow water to reach the fire.
Use a CO2 fire extinguisher if needed.
Never use a fire blanket as this will contain the fire on the patient.
Pour saline into the airway to ensure that the fire is extinguished.
Mask-ventilate the patient with air until all sources of fire are suppressed.
Re-secure the patient's airway.
Inspect the patient for injuries and treat accordingly.
Rigid bronchoscopy should be performed after an airway fire.
Follow-Up⬆⬇
Once the fire has been extinguished, evaluate the extent of the fire damage. Discuss with the surgeons whether or not to continue with the case. Each decision should be made based on fire damage, urgency of the surgery, and patient stability.
Maintain a very low threshold of leaving the patient intubated as smoke inhalation injury may have occurred, but edema may be delayed.
If the patient was awake when the fire erupted, he/she may recall the smell of the flames and the resulting pain. Consider psychiatry consult, be empathetic, and explain the event.
Consult the plastic surgeon for the management of skin and airway burns (4).
Closed Claims Data
ASA currently has only task guidelines; however, there will soon be mandates that everyone must follow.
17% of anesthetic malpractice claims are related to burns from surgical fires (4).
References⬆⬇
YardleyIE, DonaldsonLJ.Surgical fires, a clear and present danger. Surgeon. 2010;8:87–92.
Orhan-SungurM, KomatsuR, ShermanA, et al.Effect of nasal cannula oxygen administration on oxygen concentration at facial and adjacent landmarks. Anaesthesia. 2009;64:521–526.
ECRI. New clinical guide to surgical fire prevention. 2009;314–329.
NishiyamaK, MakikoK, KodakaM, et al.Crisis in the operating room: Fires, explosions and electrical accidents. J Artif Organs. 2010;13(3):129–133.
American Society of Anesthesiologists Task force on Operating Room Fires. Practice advisory for the prevention and management of operating room fires. Anesthesiology. 2008;108(5):786–801.
Additional Reading⬆⬇
BhanankerSM, PosnerKL, CheneyFW, et al.Injury and liability associated with monitored anesthesia care: A closed claims analysis. Anesthesiology. 2006;104:228–234.
Recognize which surgical procedures are high risk for operating room and airway fires (tonsillectomy, tracheostomy, cataract, creation of burr hole, carotid endarterectomy).
Vigilance is of utmost importance when caring for a patient undergoing a high-risk procedure with a natural airway and open oxygen source. Minimizing or eliminating enriched oxygen delivery is fundamental in preventing fires.
Convert quickly to GA with a secured airway if the patient is not able to tolerate an FiO2 <30%.
Consider the possibility of smoke inhalation injury that can result from thermal injury to the airways, particulate irritation, and gaseous-related injury.