Use of Wrong Gas in Laparoscopic Insufflator Causes Fire (Update)
Hazard Update [Health Devices Oct-Nov 1994;23(10-11):456-7]
In our original Hazard Report on a fire that occurred during laparoscopic
surgery (see Health Devices 23[1-2], Jan-Feb 1994), we noted that pin indexing of
medical gas cylinders and yokes can help prevent the use of the wrong gases with
laparoscopic insufflators and thus avert risks such as the reported fire. In that
incident, a cylinder containing a mixture of carbon dioxide and oxygen in a 20:80
proportion, respectively, was used instead of a cylinder of carbon dioxide only.
We have since learned that the Compressed Gas Association's (CGA) Pamphlet
V-1, Compressed Gas Cylinder Valve Outlet and Inlet Connections, defines the same
pin-indexing combination (No. 940) for carbon dioxide as for carbon dioxide and oxygen
mixtures (with over 7.5% carbon dioxide). This presents an increased risk that a cylinder
of oxygen-enriched gas can be connected to an insufflator's gas yoke, possibly leading to
a pneumoperitoneal fire during laparoscopic surgery.
Also, some hospitals and suppliers use nonstandard color-marking schemes
for their medical gas cylinders; this can lead to confusion and possibly application of
the wrong gases.
The primary means of identifying which medical gas is contained in a
cylinder, and thus of guarding against use of the wrong gas, is reading the cylinder's
label; therefore, cylinders with damaged or unreadable labels should not be used. The
secondary means of guarding against use of the wrong medical gas cylinder is pin indexing;
however, as our original report pointed out, pin indexing should not be relied on as the
sole means of identifying the gas. The cylinder color is the tertiary means of identifying
the cylinder's contents and also helps with cylinder sorting.
Carbon dioxide–oxygen mixtures of greater than 7.5% carbon dioxide
are suffocating gases not typically used for patient administration and therefore have
historically been grouped with carbon dioxide in the pin-indexing system. ECRI believes
that the standard pin-indexing system should be changed to preclude use of the wrong gas
and a potential fire, especially considering the increasing frequency of laparoscopic
surgery. We have asked CGA to review this problem, and the association reports that it
will be making appropriate changes. Until these changes can be made, which may take as
long as five years, users must be careful to ensure that the proper gas (e.g., carbon
dioxide) is used for insufflation.
In addition, the lack of a standard universal color-marking scheme for gas
cylinders can create confusion. In the United States, most gas suppliers and hospitals
follow the standard color-marking scheme defined in CGA Pamphlet C-9, Standard Color
Marking of Compressed Gas Containers Intended for Medical Use. This color scheme is
used for visual gas identification on most medical devices and is the scheme that the Food
and Drug Administration (FDA) suggests be used for medical gas containers in its Good
Manufacturing Practices (GMP) guideline, Compressed Medical Gases Guidelines. Other
countries use the color markings specified in the International Organization for
Standardization's (ISO) Gas Cylinders for Medical Use—Marking for Identification
of Contents (ISO 32). In all countries, gray is used to identify carbon dioxide
cylinders; in the United States, gray and green are used for carbon dioxide–oxygen
mixtures, while gray and white are used in other countries.
- Do not use medical gas cylinders with missing,
damaged, or obscured labels.
- Ensure that insufflator gas cylinder yokes are pin indexed to allow
connection of only the proper insufflation gas (e.g., carbon dioxide).
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, for example:
Insufflation Gas: Carbon
Dioxide--Use Gray Tanks Only.
- Ensure that all operating room personnel and
support technicians who deal with medical gases know and understand the
color-marking scheme. All users and suppliers should use the standard color
scheme for their country. In all countries, carbon dioxide–only
cylinders are gray with no second color.
- During the pre-use check, ensure that only the
insufflation gas specific for the insufflator and requested by the surgeon
is used. Question the use of gases other than carbon dioxide. Note and
record on the surgical record the label on and color of the gas cylinder
attached to the insufflator.
- Store gas cylinders in a manner that will minimize the risk that the
gases will be confused (e.g., store special mixed gases separately).
- Medical Gas Cylinders [16-501]
- Insufflators, Laparoscopic [16-849]
Cause of Device-Related Incident
Device factor: Design/labeling error
User errors: Failure to perform pre-use
inspection; Failure to read label; Improper connection
External factor: Medical gas and vacuum supplies
Support system failures: Failure to train
and/or credential; Lack or failure of incoming and pre-use inspection
Mechanism of Injury or Death
Burn (thermal); Fire