Electrosurgical Airway Fires Still a Hot Topic
Hazard [Health Devices Jul 1996;25(7):260-1]
ECRI continues to receive many reports of electrosurgical airway fires and
to investigate a number of them. Although these fires are often mistakenly attributed to
malfunction of electrosurgical units (ESUs) used during surgery, in our experience they
are actually the result of other factors. Airway fires are very serious and, if not
quickly extinguished, can be deadly. All surgeons, whether experienced or newly trained,
need to recognize the hazards presented by using ESUs in the oxygen-enriched atmospheres
(OEAs)—atmospheres containing more than 23% oxygen—that are commonly present in
ESUs provide electrical energy that is used to cut and coagulate tissue.
The energy is delivered to the tissue through an active electrode controlled by the
surgeon. ESUs present a fire hazard in any procedure, but their use during airway
surgeries, such as tonsillectomies and tracheostomies, involves particular risks.
Too often, the ESU is initially blamed for an electrosurgical airway fire.
A typical observer will attribute the flame, sparking, and arcing seen at the surgical
site immediately before the fire to, for example, "some surge of electricity from the
ESU." But in more than 20 years of investigating such cases, we have never found
this to have occurred. The flame, sparking, and arcing are actually the accelerated
burning of tissue and of gases evolved from the electrosurgery. The true cause of the
fire, rather than the ESU itself, is typically the misuse of the ESU in the OEA that
exists in the patient's airway.
Airway surgeries frequently use oxygen and nitrous oxide to ventilate and
anesthetize patients, respectively. Both gases support combustion, and both reduce the
amount of energy (e.g., current, heat, friction) needed to ignite flammable substances.
Moreover, during airway surgery, these gases leak around the tracheal tube, its cuff, or
packing, creating an OEA in the oropharynx. Some fuels that will not burn in the 21%
concentration of oxygen found in room air will burn vigorously in an OEA.
Many flammable substances in the airway are exposed to an ESU during
airway electrosurgery. For example, a portion of the tissue heated by the ESU turns to
gas, some of which—especially those gases evolved from fatty tissue—will burn if
made hot enough or if mixed with sufficient oxygen. Another portion of the tissue is
reduced to embers, which are also flammable. Other fuels present in airway
electrosurgeries include tracheal tubes, catheters, and surgical sponges. When the tip of
the electrode heats tissue within this OEA, nearby flammable substances can easily catch
fire. For example, a flare of evolved gases can directly ignite these substances; a spark
(i.e., a tissue ember that is still incandescent) can land on and ignite a dried-out
sponge; or the inactive but still hot electrode can graze the tracheal tube or sponge and
Sudden ignition of airway fuels also presents some secondary problems: 1)
The abrupt flash and sound can create a startle reflex, causing the surgeon's hand to jerk
and potentially cut into unintended tissue or set other areas of the surgical site on
fire. 2) This startle reflex can prevent the surgeon from accurately observing the
ignition and deducing its cause.
The following are some of the specific hazards we have noted, all of which
can be avoided by proper attention to technique and by taking appropriate preventive
- For tonsillectomies, some surgeons sheathe long ESU
electrode probes with a section of red rubber catheter to prevent secondary
mouth burns to the patient. In even a slight OEA, the heat from the probe
will ignite the rubber. Long probes insulated with polytetrafluoroethylene
(Teflon) and having exposed tips are commercially available and should be
used instead because they offer the desired electrical protection, are
difficult to ignite, and burn only in an oxygen concentration of over 95%.
- During tracheostomies, some surgeons employ the
potentially fatal practice of cutting through the tracheal rings with the
ESU and entering the OEA within the trachea. If the hot electrode tip or a
tissue ember contacts the tracheal tube cuff, or the tube itself, inside the
trachea, a fire will erupt. To avoid this hazard, surgeons
should—after dissecting down to the trachea with the ESU—use
scissors or a scalpel, instead of the ESU, to cut the avascular tracheal
- Wetted sponges, gauze, or pledgets are often used to pack the trachea
around the tracheal tube to prevent leaks. Over time, these materials can
dry out, become saturated with oxygen, and thereby become a fire hazard.
Packing should be applied wet and kept wet throughout the procedure.
- Alert surgeons and anesthesiologists to the hazards
of using ESUs in the OEAs commonly present in the oropharynx and trachea.
See the references below for more detailed discussions of some of the
hazards described in this report, as well as discussions of some of the
- If long, insulated electrosurgical electrode probes
are required, use only commercially available insulated probes. Do not use
red rubber catheter or other materials to sheathe probes.
- Do not use ESUs to cut tracheal rings and enter the
airway. Using scissors or a scalpel instead will avoid the risk of fire.
- Be sure that any sponge, gauze, or pledget used in the airway is applied
wet and kept wet.
de Richemond AL, Bruley ME. Head and neck surgical fires. In: Eisele DW,
ed. Complications in head and neck surgery. St. Louis: Mosby—Year Book, 1993.
de Richemond AL, Bruley ME. Insidious iatrogenic oxygen-enriched
atmospheres as a cause of surgical fires. In: Janoff DD, Stoltzfus JM, eds. Flammability
and sensitivity of materials in oxygen-enriched atmospheres: Sixth volume. Philadelphia:
American Society for Testing and Materials (ASTM), 1993. (ASTM Special Technical
ECRI. The patient is on fire!: A surgical fires primer [Guidance article].
Health Devices 1992 Jan;21(1):19-34.
National Fire Protection Association (NFPA). Guide on fire hazards in
1994 ed. Quincy (MA): NFPA, 1994; NFPA 53.
- Electrodes, Electrosurgical, Active [16-860]
- Electrodes, Electrosurgical, Active, Foot-Controlled
- Electrodes, Electrosurgical, Active, Hand-Controlled
- Electrosurgical Units [11-490]
- Electrosurgical Units, Bipolar [18-230]
- Electrosurgical Units, Monopolar [18-299]
- Electrosurgical Units, Monopolar/Bipolar
- Gauze [11-859]
- Pledgets [13-055]
- Sponges, Gauze [13-700]
- Sponges, Scrub [15-281]
- Tubes, Tracheal [14-085]
Cause of Device-Related Incident
User errors: Failure to read label; Incorrect clinical use
External factor: Medical gas and vacuum supplies
Support system failures: Failure to train
and/or credential; Use of inappropriate devices
Mechanism of Injury or Death