Use of Wrong Gas in Laparoscopic Insufflator Causes Fire
Hazard [Health Devices Jan-Feb 1994;23(1-2):55-6]
In preparation for laparoscopic surgery, a technician was directed to
obtain a full "E" cylinder of carbon dioxide for the laparoscopic insufflator.
From the storage area, the technician obtained a cylinder that was gray on top and green
on its lower section and that had only part of a label that read "Carbon
Dioxide." The technician connected the cylinder to the gas yoke of the insufflator,
and the surgery proceeded.
Near the end of the procedure, the operative field rapidly became obscured
by black smoke. After withdrawing the electrosurgical probe, the surgeon found that the
probe's insulation had been burned away and that the trocar sheath had partially burned
and melted. The patient most likely sustained severe burns to the internal abdominal wall
and bowel, although the injuries have not been confirmed.
A combination of errors contributed to this incident. The technician was
not aware of the U.S. national standard color-coding scheme for marking medical gas
cylinders (based on the Compressed Gas Association's [CGA] Pamphlet C-9, Standard Color
Marking of Compressed Gas Containers Intended for Medical Use). For example, according
to this standard, gray indicates carbon dioxide, green indicates oxygen, and a combination
of colors indicates a mixture of gases designated with those colors. Relying only on the
partial label, the technician thought he had obtained a carbon dioxide cylinder, but had
actually obtained a cylinder containing a mixture of carbon dioxide and oxygen (as
indicated by the two colors) in a 20:80 proportion, respectively.
The technician was able to install the incorrect cylinder in the
insufflator's gas yoke because the indexing pins, designed to prevent connection of an
incorrect gas cylinder, had been removed from the yoke. (Also see our Hazard Report,
"Improper Connection of Laparoscopic Insufflators and Gas Cylinders," Health
Devices 21, May 1992, for discussion of a similar problem.)
No one in the operating room recognized that the colors on the gas
cylinder indicated that the wrong tank had been connected. Because of the 80% oxygen
concentration in the pneumoperitoneum, either a small tissue ember or heat from the
electrosurgical probe ignited the probe's insulation, causing the fire.
- Ensure that insufflator gas cylinder yokes are pin
indexed to allow connection of only the proper insufflation gas, typically
carbon dioxide (although nitrous oxide and helium are sometimes used and
require gas-specific yokes). Routinely inspect the yokes (e.g., during
scheduled inspection and preventive maintenance) for proper and intact
indexing pins. Do not remove indexing pins, and do not purchase or accept
delivery of yokes that have no pins. Label the insufflator with the type of
gas with which it is to be used (e.g., "Insufflator Gas: Carbon
Dioxide. Use gray tanks only.").
- Instruct operating room personnel and support technicians about medical
gas cylinder color coding, and instruct them to check that the color of the
insufflator cylinder indicates the gas intended for the procedure. In the United States, green indicates oxygen; gray, carbon dioxide;
yellow, medical compressed air; blue, nitrous oxide; black, nitrogen; and brown, helium.
(Other countries use color markings specified in the International Organization for
Standardization's [ISO] Gas Cylinders for Medical Use—Marking for Identification
of Contents [ISO 32].) Gas mixtures are indicated by two
or more designated colors on the cylinder.
- Store gas cylinders in a manner that will minimize the risk of confusing
gases (e.g., store special mixed gases separately).
- Medical Gas Cylinders [16-501]
- Insufflators, Laparoscopic [16-849]
Cause of Device-Related Incident
User errors: Abuse of device; Failure to read label; Improper connection
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
Burn (thermal); Fire