Risk of Ineffective Assisted Ventilation Using Fenestrated Tracheostomy Tubes with 15 mm Connectors
Hazard [Health Devices Oct 1995;24(10):422-3]
A hospital reported a case of ineffective emergency
ventilation of a patient in respiratory arrest when a manual resuscitator was connected to the
15 mm male connector on the fenestrated inner cannula positioned inside a
fenestrated low-pressure cuffed tracheostomy tube. During the resuscitation attempt,
significant portions of the administered gas escaped through the fenestrations in both the
inner cannula and the outer tube. Rather than entering the lungs, this gas exited through
the patient's mouth and nose.
Serious injury did not occur because the tube's fenestrated inner cannula
was quickly replaced with a nonfenestrated one. However, this problem could lead to a
life-threatening situation if effective ventilation does not occur in a timely manner.
Note that similar problems could occur with several manufacturers'
fenestrated tracheostomy tubes, as discussed below. Also, even facilities that do not
purchase one of the affected products may encounter such tubes in patients brought to the
facility from a long-term care or home-care setting.
Fenestrated tracheostomy tubes are typically used during weaning of
tracheostomy patients from mechanical ventilators or from their artificial airway. These
tubes have a hole (or holes) in the wall of the inserted portion that allows the patient
to breathe through his mouth and nose. The exposed end of the tube often has a 15 mm
connector to allow attachment to a ventilation device (e.g., a mechanical ventilator). In
most designs, this connector is located either on the tube itself (outer tube) or on a
nonfenestrated inner cannula, which is inserted in the outer tube when the fenestration
needs to be occluded (e.g., for manual or mechanical ventilation). The tube used in the
reported incident is supplied with a fenestrated and a nonfenestrated inner cannula, both
of which include a 15 mm connector.
During the weaning process, the exposed end of the tracheostomy tube is
often occluded with a decannulation cap or plug, forcing the patient to breathe through
the fenestration and his upper airway. If manual or mechanical ventilation is required,
the cap or plug and, if present, the fenestrated inner cannula are removed, and a
nonfenestrated inner cannula is inserted. The ventilation device is then connected to the
tube's 15 mm connector, and the ventilation gas is directed into the lungs.
The reported problem was able to occur because the fenestrated tube could
be connected to a ventilation device without first occluding the fenestration. In this
case, the use of a fenestrated inner cannula equipped with a 15 mm connector made the
In January 1994, the manufacturer of the
incident tube began packaging all of its Shiley fenestrated low-pressure cuffed
and cuffless tracheostomy tubes with a fenestrated inner cannula equipped with a 15 mm twist-lock connector in addition to the
nonfenestrated inner cannula that had been previously supplied. However, the products with both
types of inner cannulas were marketed under the same product designation as those with only the
In addition, the packaging differed only slightly: a sticker was added to the outer box,
and a separate addendum was included in the instructions for use. Therefore, purchasers
may not be aware that the package includes a fenestrated inner cannula, and users may misuse
ECRI is aware of other manufacturers' fenestrated tracheostomy
tubes that also provide access to a 15 mm connector without occluding the fenestrations
in the outer tube. Although we are not aware of any reported problems or complaints
related to this type of incident with the other products, user confusion or
misuse could lead to a similar situation of inadequate ventilation.
Also, other tracheostomy tube manufacturers will, on request, offer
products that provide access to a 15 mm connector without occluding any fenestrations in
the outer tube. These custom-made fenestrated tracheostomy tubes pose the same risk of
inappropriate connection to assisted ventilation devices.
Note that a variety of warning mechanisms are provided with
some tubes in an attempt to alert clinicians to the potential for
inappropriate connection to manual resuscitation or mechanical ventilation devices. In
addition, a nonfenestrated inner cannula is packaged with these products for use when
assisted ventilation becomes necessary. Such warning mechanisms may not be provided with
custom tubes supplied by other manufacturers.
- Warn all personnel trained in airway support that a
tracheostomy tube may be fenestrated and therefore may be inappropriate to
use for assisted ventilation—even if the tube has a 15 mm connector.
- Instruct personnel to insert a nonfenestrated inner
cannula, if available, before attempting assisted ventilation through a
fenestrated tube. Be sure personnel are trained to check for adequate
ventilation and know what to do if adequate ventilation cannot be achieved
through a tracheostomy tube (regardless of the reason).
- Identify all fenestrated tracheostomy tubes at your
institution, and do the following:
A. Mark any
packages that do not have appropriate labels with an applicable warning,
such as "DO NOT USE FOR MANUAL OR MECHANICAL VENTILATION" or
"INSERT NONFENESTRATED INNER CANNULA FOR ASSISTED VENTILATION" or
a suitable equivalent. A similar warning should be kept in the vicinity of
the patient, even during transport.
follow the manufacturer's instructions for use, as well as all package
and/or product labeling and warnings.
C. Verify that
all appropriate accessories (i.e., a nonfenestrated inner cannula) and
spares are immediately available, even during transport, in case assisted
ventilation becomes necessary.
References from Health Devices
Misuse of fenestrated
tracheostomy tubes [Hazard Report]. 1978 Jan;7(3):91.
- Tracheostomy Tube Adapters
- Tubes, Tracheostomy
Design/labeling error; Packaging error
User errors: Failure
to read label; Improper connection; Incorrect clinical use
Support system failure: Use of inappropriate
Mechanism of Injury
Failure to deliver