The Food and Drug Administration (FDA) has issued a Safety Communication regarding implantable pumps used for drug administration and the risks of using medications not approved for use with the pumps to treat or manage pain. These risks include pump failure, dosing errors, and other patient safety concerns.

Implantable pumps are medical devices that have been surgically implanted, usually in the abdomen, and connected to an implanted catheter that delivers medication to a location within the body. They are often used to deliver pain medication via intrathecal administration into the spinal fluid when other therapies, such as oral medications or surgery, haven't been successful. The pump is periodically refilled by a health care provider.

Specific pain medications have been approved for use in implantable pumps. Use of a drug for an off-label purpose is not illegal or necessarily poor practice. Practitioners should be aware, however, that pain medicines approved for intrathecal infusion via implantable pumps must meet additional safety standards in order to avoid damage to the brain and spinal cord from preservatives or infection.

The FDA's recommendation to use only approved medications in implantable pumps is based on medical device reports received and reviewed by the FDA related to pump failure, dosing errors, and other potential patient safety concerns. The FDA's review finds that use of unapproved pain medications in implantable pumps contributes to pump failure at more than twice the rate of approved pain medications. Not all medications, such as compounded medications, have been evaluated for compatibility with pump components. The use of any of these drugs, such as those containing preservatives, could damage the pump tubing or corrode the pumping mechanism. The FDA concludes that use of unapproved medications is associated with "an increased risk for part failure that may lead to earlier than expected surgical removal or replacement of the pump."

Dosing errors are also associated with the use of unapproved drugs in implantable pumps. The accuracy of the dose calculation software within these pumps is dependent on using preprogrammed medications and medication concentrations. For example, combining medications in the pump reservoir prevents the software from calculating the proper dose. In addition, when practitioners use a higher concentration of a drug than the software program recognizes, they may try to offset the risk of overdose by slowing the infusion rate. However, overriding the safety features of the software and creating unique dosing for a drug increases the risk of a programming error. The FDA also notes that the pumps have technical limitations and flow rate errors can occur if the infusion rate is too low, causing the patient to receive too little medication.

Other potential safety issues with the use of unapproved pain medications in implanted pumps include damage to the spinal cord or brain tissue, central nervous system infections, and granuloma formation at the tip of the catheter or infusion site that occurs with high concentrations of medications. Granuloma formations are inflammatory masses that can compress the spinal cord or nerves, producing pain and neurologic deficits.

Nurses and other health care providers who work with patients receiving intrathecal delivery of pain medication through an implantable pump are urged to carefully read the pump's labeling information to identify which medications are specifically approved for use with the pump. The FDA warns that the following drugs are not approved for implantable pumps and should be avoided:

* medicines not approved by the FDA for intrathecal administration or intrathecal implanted pump use (such as hydromorphone, bupivacaine, fentanyl, and clonidine)

* any mixture of two or more medicines

* any compounded medications (compounded, for example, to achieve a higher concentration or different formulation of an FDA-approved drug)

Nurses and other health care providers should report any adverse effects related to implanted pumps to the FDA's MedWatch program at http://www.fda.gov/Safety/MedWatch/HowToReport/ucm2007306.htm. To read the FDA Safety Communication regarding implanted pumps, go to http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm625789.htm.