Management of symptomatic intrathecal catheter-associated inflammatory masses

Symptomatic Intrathecal Catheter Tip Granuloma Formation With Ultralow-Dose and Low-Concentration Morphine Infusion: A Case Report and Review of Literature

OBJECTIVES

This study aimed to describe catheter tip granuloma (CTG) formation in a patient on ultralow-dose, low-concentration morphine via intrathecal (IT) drug delivery system (IDDS) and to review literature for reports of IT granuloma formation and association with drug type, drug dose, and drug concentration.

MATERIALS AND METHODS

This review describes diagnosis and management of a patient with CTG on ultralow-dose, low-concentration morphine. PubMed data base search was conducted from January 1990 to July 2021 for original articles on CTG formation in humans getting intrathecal analgesics. Data were extracted on indications for IDDS, time to detect CTG, and type of drug/s with drug doses and concentrations. Percentages and average with range for age, sex, duration of infusion, drug doses, and drug concentrations were calculated.

RESULTS

We describe CTG formation and spinal cord compression with worsening of sensorimotor deficits in a patient receiving intrathecal morphine at ultralow dose (0.6 mg/d) and low concentration (1.2 mg/mL), which is the lowest reported morphine dose associated with CTG in the literature. Our literature review shows all IT drugs have the potential for granuloma formation, and there is no drug with granuloma-inhibiting effect.

CONCLUSIONS

There is no drug, dose, or concentration that has granuloma-sparing effect. It is imperative to maintain vigilance for potential CTG in all patients with IDDS. Routine monitoring and prompt evaluation for any unexplained symptoms or change in neurologic status from baseline is critical in early detection and treatment of CTG.

The Management of Unresectable Intrathecal Catheter-Tip-Associated Granuloma Using Morphine Therapy Cessation and Spinal Cord Stimulation

Catheter-tip-associated granulomas (CTG) are a rare but serious complication of intrathecal analgesic delivery pumps (IADP), which interfere with pain modulation and can cause irreversible neurologic deficits. The treatment of symptomatic CTG generally involves surgical resection and catheter removal. We present a case of an unresectable CTG, which we managed using progressive lowering of the intrathecal morphine sulfate (ITMS) dosage as well as spinal cord stimulation (SCS). A 55-year-old female with failed back surgery syndrome (FBSS) presented with new-onset left-sided lumbar radiculopathy after five years of moderately successful ITMS therapy. An MRI study suggested an unknown mass associated with the tip of the catheter. The tumor’s adherence to nerve roots of the conus terminalis prevented a complete resection and only allowed for a biopsy. After the SCS implantation, we progressively lowered the ITMS dose. In a follow-up consultation, the patient reported the regression of the radiculopathy as well as satisfactory pain levels without oral opiates. In this case of CTG, cessation of intrathecal morphine prevented the further growth of the granuloma. SCS effectively addressed both the chronic lumbar back pain as well as the new-onset radicular pain caused by the CTG.

Injury and Liability Associated with Implantable Devices for Chronic Pain

BACKGROUND

Due to an increase in implantable device-related anesthesia pain medicine claims, the authors investigated anesthesia liability associated with these devices.

METHODS

After institutional review board approval, the authors identified 148 pain medicine device claims from 1990 or later in the Anesthesia Closed Claims Project Database. Device-related damaging events included medication administration events, infections, hematomas, retained catheter fragments, cerebrospinal fluid leaks, cord or cauda equina trauma, device placed at wrong level, stimulator incorrectly programmed, delay in recognition of granuloma formation, and other issues.

RESULTS

The most common devices were implantable drug delivery systems (IDDS; 64%) and spinal cord stimulators (29%). Device-related care consisted of surgical device procedures (n = 107) and IDDS maintenance (n = 41). Severity of injury was greater in IDDS maintenance claims (56% death or severe permanent injury) than in surgical device procedures (26%, P < 0.001). Death and brain damage in IDDS maintenance claims resulted from medication administration errors (n = 13; 32%); spinal cord injury resulted from delayed recognition of granuloma formation (n = 9; 22%). The most common damaging events for surgical device procedures were infections, inadequate pain relief, cord trauma, retained catheter fragments, and subcutaneous hygroma. Care was more commonly assessed as less than appropriate (78%) and payments more common (63%) in IDDS maintenance than in surgical device procedure claims (P < 0.001).

CONCLUSIONS

Half of IDDS maintenance claims were associated with death or permanent severe injury, most commonly from medication errors or failure to recognize progressive neurologic deterioration. Practitioners implanting or managing devices for chronic pain should exercise caution in these areas to minimize patient harm.