Hazard [Health Devices Jan 1995;24(1):36-8]

Problem

A member hospital reported a fatal central venous air embolism caused by the separation of a specific manufacturer's side port/hemostasis valve catheter-to-sheath adapter from the same manufacturer's percutaneous sheath hub. The accident occurred when the standard Luer-lock fitting disconnected as a patient was moved from a bed to a chair.

Review of FDA problem reporting databases revealed other reports of fatalities due to air embolism, as well as exsanguination, involving the same manufacturer's side port/hemostasis valve adapters from its introducer sheaths. The databases also include numerous other reports of disconnection of the side port/hemostasis valve adapter, many of which were associated with serious injury. In addition, a letter in Anesthesiology discusses two cases of air embolism associated with this manufacturer's vascular access system, one of which was fatal.(1)

Percutaneous sheath introducers are used to insert and maintain cardiac catheters, for example, into the pulmonary artery. They are available in two design configurations featuring either a one-piece (nondetachable) version or a two-piece (detachable side port/hemostasis valve adapter) version.

In the two-piece design, the side port/hemostasis valve adapter, which includes a hemostasis valve and a short length of IV tubing bonded to a side port, is attached to the introducer sheath hub with a Luer-lock connector (see figure). When assembled, the cardiac catheter passes through the hemostasis valve and sheath into a central vessel (usually the jugular and occasionally the subclavian vein). While the cardiac catheter is in place, the side port can be used for central venous therapy. When the cardiac catheter is removed, an obturator cap must be inserted into the hemostasis valve; the side port can then continue to be used for short-term central venous access in closely monitored critically ill patients, in whom gaining new central venous access may be difficult.

According to the manufacturer, even though the one-piece design is more aggressively promoted, the two-piece design is in wider clinical demand. (Other manufacturers also offer a two-piece design—usually packaged as part of full-procedure kits—that may be susceptible to separation.) Both sheath introducer designs feature a suture tab to permit the hub to be secured to the patient's skin and lessen the likelihood of inadvertently removing the sheath if traction is placed on the hub. Suturing the sheath in place also limits its freedom to rotate, particularly if the hub is fixed using the suture tab. However, in the two-piece design with the hub anchored (sutured), which is typical, tension placed on the side port tubing could untwist and detach the side port/hemostasis valve adapter, allowing bleeding or air ingress. The physician must determine which design is appropriate to avoid potentially dangerous situations in which the assembly is left indwelling for central venous access.

The following may constitute clinical advantages for the use of a two-piece catheter introducer:

• Removing the side port/hemostasis valve adapter and connecting a large-bore resuscitation line directly to the large-bore sheath permits high-volume fluid replacement in emergencies.
• Having a detachable side port/hemostasis valve adapter permits testing of the cardiac catheter's balloon integrity after it is inserted through the valve and before it is inserted into the sheath introducer.
• The ability to replace the side port/hemostasis valve adapter with an adapter that has a smaller hemostasis valve permits use of other instruments (e.g., temporary pacemaker leads can be introduced through the sheath).

1. Whenever possible, use cardiac catheter introducers in which the side port/hemostasis valve is an integral part of the sheath hub.
2. Do not use sheath introducers with detachable side port/hemostasis valves on agitated or disoriented patients.
3. If an introducer with a detachable side port/hemostasis valve is used, loop and securely tape the IV tubing of the side port to the patient's skin, and avoid placing traction on tubing attached to the side port.
4. Discontinue use of any sheath introducer vascular access system as soon as possible following cardiac catheter removal.

1. Hartung EJ, Ender J, Sgouropoulou S, et al. Severe air embolism caused by pulmonary artery introducer sheath [letter]. Anesthesiology 1994 Jun;80(6):1402.

UMDNS Terms

• Catheter Introducers, Hemostasis Valve [17-578]
• Catheters, Cardiac [10-698]

Device factor: Design/labeling error

User error: Incorrect clinical use

Support system failure: Poor prepurchase evaluation

Embolism (gaseous); Exsanguination