With the increase in use of intrathecal pain pumps for pain and spasticity, the author of a recent report highlights that there is a small but significant number of problems due to their use. One such complication is the formation of an inflammatory mass called a granuloma at the tip end of the catheter. The catheter tip is placed in the spinal canal so in some cases has caused neurological problems such as weakness and even paralysis. Catheter tip granulomas are thought to occur at a rate of three percent presently. This complication is expected to increase with the growing number of patients having the device implanted, and as patients receive infusions for longer periods of time.
Morphine for pain, and baclofen for spasticity, are the most common medications delivered by the intrathecal pump. Granuloma formation seems to be less common in those using baclofen. Ziconotide is a newer medication approved for use in chronic pain. It was felt that granulomas may be the result of compounding, or using a combination of medications as well as medications that were approved for use in the intrathecal pump. However, studies have shown that high doses and concentrations of morphine increase the risk for granuloma. This risk has also been shown to be cumulative over time.
Other complications include malfunction of the intrathecal pump; fracture, clogging, and dislodgement of the catheter, and human error to include accidental overdose.
New catheter materials, sensors to monitor amount of drug in the pump, and improved pump reliability are some of the new technologies that should improve patient safety.
T. Agres, As use of pain pumps expands, scope of problems with devices becomes clearer. Pain Medicine News. March 2008. Volume 6. Number 3. Page 1.'