Electrosurgical Unit Activation Tone Control
Hazard [Health Devices Nov 1985;14(13):407]
ECRI continues to receive problem reports and investigate incidents of
burns caused by inadvertent activation of electrosurgical units (ESUs). Liability and
malpractice litigation often follow such injuries. The frequency and severity of these
incidents can be greatly reduced if the volume control for the ESU activation tone is
maintained at an audible level. Some surgeons are disturbed by the tone and turn the
volume down to an inaudible level, risking undetected activation of the ESU and possible
injury to the patient. The activation tone on ESUs is an important safety feature that
should never be neglected or disabled, regardless of the personal preferences of surgeons
or other members of the operating team.
Manufacturers have tried to resolve this dilemma in two ways. The first
approach, used by some manufacturers, is to produce ESUs with an adjustable-volume tone
that cannot be silenced. These manufacturers can provide a modification that will silence
the activation tone. However, the hospital must sign a document that releases the
manufacturer from responsibility for accidents resulting from this modification. Thus, the
manufacturer-installed tone that cannot be silenced ensures that the device will be
safeguarded against inadvertent, undetected activation unless the hospital chooses to
override this safety feature.
The second approach, used by those manufacturers who produce ESUs that can
be silenced, is to provide, upon request, modification instructions to set a low-volume
limit to ensure that the tone remains audible. This approach is less desirable since it
requires the initiative of the surgeon or clinical engineer.
In addition to ECRI, both the Association for the Advancement of Medical
Instrumentation (AAMI) and the International Electrotechnical Commission (IEC) support
low-volume limits on ESU activation tones. But their recommendations are routinely
ignored. Some surgeons claim that the activation tone upsets conscious patients undergoing
surgery. However, simply explaining the tone to the patient should reduce this anxiety. We
acknowledge that during microsurgery on a conscious patient, the onset of the activation
tone may startle the patient and possibly lead to a surgical mishap. (One surgeon reports
that he provides his patients with headphones to mask disturbing noises, enabling him to
maintain an audible activation tone volume.)
The majority of surgeons opposed to the activation tone are irritated by
the quality of the tone. Some individuals have suggested that a less annoying tone would
be more acceptable. However, surgeons must be made aware that disabling this safety
feature exposes their patients to the possibility of accidental electrosurgical burns. One
burn incident we investigated occurred when a patient's leg was moved during surgery. The
patient's heel was mistakenly placed on the electrosurgical pencil, activating the unit
and causing third- and fourth-degree burns on the foot. Had the activation tone been
audible, the severity of this accident would have been greatly reduced.
- Alert all users of ESUs to this report. Discuss the
importance of using the activation tone during electrosurgery with your
hospital's administrator and risk manager, and ask them to advise your
hospital's chief of surgery about the risks related to the reported problem.
- Placard a warning on ESUs that can be silenced; for
example "WARNING: The activation tone is an important safety feature.
DO NOT turn it down to an inaudible level."
- Listening to music in the OR risks masking the
audible alarms of ESUs and other devices. If music is permitted, be sure
that alarms can still be heard.
- Contact the manufacturer of your ESUs to determine
what modifications are needed to set a low-volume limit to ensure that the
tone remains audible.
- Verify that the activation tone functions at the minimum control setting
during all acceptance and routine ESU inspections. Check the ESUs in
inventory to be sure the activation tone is functioning properly.
- Electrosurgical Units [11-490]
- Electrosurgical Units, Bipolar [18-230]
- Electrosurgical Units, Monopolar [18-229]
- Electrosurgical Units, Monopolar/Bipolar [18-231]
Cause of Device-Related
Device factor: Design/labeling error
User error: Incorrect control settings
Mechanism of Injury or Death