Fires from Defibrillation during Oxygen Administration
Hazard [Health Devices Jul 1994;23(7):307-8]
ECRI continues to receive reports and investigate incidents of patients
and their bedding being set on fire during defibrillation. In these cases, defibrillation
was performed in the presence of oxygen administration devices, which are necessary in
resuscitation attempts and which inherently spill excess oxygen. This oxygen enriches the
space around the patient's head and chest and allows an electric arc sometimes produced
during defibrillation discharge to ignite body hair. The fire flashes rapidly over the
patient, consuming body hair and igniting nearby bedding materials and medical devices.
ECRI has discussed this problem in Health Devices twice previously;
see the Hazard Report "Defibrillation in Oxygen-enriched Environments"
(16[3-4]:113-4, Mar-Apr 1987) and the Consultant's Corner article "Electrical
Equipment during Oxygen Administration" (9:47-8, Dec 1979). Also, the medical
literature includes references to this hazard as early as 1972. However, even though the
problem has been recognized for a long time, incidents of fire during defibrillation in
oxygen-enriched atmospheres (OEAs) continue to occur. This suggests that the ignition
danger during defibrillation has been forgotten or ignored—or was never
learned—and must be periodically reemphasized to minimize the incidence of this kind
During external defibrillation, electrical energy is delivered to an
erratically beating heart through paddles, or sometimes disposable defibrillation
electrodes, that are placed on the surface of the skin. If a good interface between the
defibrillation paddles and the patient's skin is not established, an electric arc can
result. A poor interface can be caused by insufficient force during paddle application, an
insufficient or excessive amount of conductive gel, use of the wrong gel (e.g., ultrasound
gel), application of paddles over irregular surfaces (e.g., bony prominences, wires, ECG
electrodes), or misapplication of paddles to disposable defibrillation pads (e.g., the
metal surface of the paddle not completely on the pad, a fold in the pad, a pad smaller
than the paddle's metal surface, a dry pad). Placing a paddle close to an ECG electrode
can also cause an arc.
Although an arc may cause minor damage to the paddle surface or cause
insufficient energy delivery to the heart, it will not cause a fire in room air. However,
if a localized OEA is in the vicinity of the arc (e.g., on the bedding, around the
patient's upper body), the energy contained in the arc can be sufficient to ignite body
hair and the surface nap fibers on most fabrics. Then, in a phenomenon called
"surface-fiber flame propagation (SFFP)," the fire flashes over the
oxygen-enriched surface, often without burning the skin or underlying fabric, as each
small hair or fiber ignites hairs or fibers nearby until the flame front meets an edge
(e.g., hem or fold of cloth, area of near-ambient oxygen concentration) and either
establishes a flame at the edge or burns out. In most cases, the flame front races toward
the source of the oxygen enrichment and can result in ignition of the supply tubing or
device. (See Bruley ME, Lavanchy C. Oxygen-enriched fires during surgery of the head and
neck. In: Stoltzfus J, Benz FJ, Stradling JS, eds. Symposium on flammability and
sensitivity of materials in oxygen-enriched atmospheres: Fourth volume, ASTM STP 1040.
Philadelphia: American Society for Testing and Materials [ASTM], 1989.)
Defibrillation performed in the presence of oxygen does not typically
result in a fire. However, if the localized oxygen concentration is significantly above
ambient in the vicinity of the potential ignition point (i.e., the paddles), a flash fire
may result. The oxygen concentration in this vicinity will depend on such factors as the
oxygen flow rate, the position and direction of the oxygen outflow, the time oxygen has
been flowing, the position of the patient, and nearby movement of people and devices.
Regardless of the factors involved, the OEA will typically extend less than a foot in any
direction from the outflow point and will quickly return to ambient when the source of
enrichment is removed.
Fires during defibrillation can be prevented by 1) minimizing the
presence of oxygen-enriched spaces around the patient's head, neck, and upper body and 2)
reducing the chance of arcing by establishing a good interface between the defibrillator
paddles and the patient's skin. To meet these requirements, do the following:
- Remove all sources of
supplemental oxygen from the area around the patient before a defibrillation
attempt to prevent zones of high oxygen concentration in the vicinity of the
paddles. This includes all manual and gas-powered resuscitators, breathing
circuits, masks, and nasal cannulae that provide oxygen at concentrations
above 21%. Do not leave such devices near the patient or on the bed when
clearing for a defibrillation discharge because the outflow of oxygen can
maintain an enriched space.
- Reduce the risk of arcing during defibrillation by:
- Applying the defibrillator paddles firmly
with as much force as possible (the American Heart Association
recommends 25 lb per paddle) while ensuring even and unobstructed
contact with the patient's skin or disposable defibrillation pads.
- Applying ECG electrodes as far from
defibrillation paddle sites as possible. Do not place defibrillator
paddles on an ECG electrode or wire.
- Using pads that are larger than the metal surface of the paddle,
that have not reached their expiration date, and that are wet (if
using disposable defibrillator pads).
- Review and revise existing defibrillation protocols to include
techniques, such as those above, to reduce the risk of arcing in an OEA.
Preventive measures must not interfere with the resuscitation attempt or
jeopardize its success.
- Defibrillator/Monitors [11-129]
- Defibrillator/Monitors, Line-Powered [15-029]
- Defibrillators [11-132]
- Defibrillators, Battery-Powered [11-134]
- Defibrillators, Line-Powered [11-137]
- Resuscitators [13-360]
- Resuscitators, Pulmonary [13-364]
- Ventilators [15-613]
Cause of Device-Related Incident
User errors: Failure to perform pre-use inspection; Incorrect clinical use
External factor: Medical gas and vacuum supplies
Mechanism of Injury or Death