Hayek, S.M., Deer, T.R., Pope, J.E., Panchal, S.J., & Patel, V. (2011). Intrathecal therapy for cancer and non-cancer pain. Pain Physician, 14, 219–248.

Databases searched were PubMed, EMBASE, and Cochrane Collaboration.

Search keywords were intrathecal pump for pain, intrathecal infusion, spinal infusion, intrathecal drug delivery system, spinal pump, and intrathecal therapy.

Studies were included in the review if they

• Involved long-term use of intrathecal infusion implants for chronic pain.
• Provided a minimum of three-months follow up.
• Reported on patients with no previous spinal surgery.
• Used any study design.

Studies were excluded if they

• Lacked clear delivery system documentation or used mixed delivery systems.
• Were case reports, technical reports, surveys, or pump evaluations.

The initial search yielded 812 references; 59 of these were reviewed. A final sample of 20 studies was included. Of these, one randomized trial and four observational studies involved cancer pain. Study quality was evaluated using Agency for Healthcare Research and Quality (AHRQ) criteria for observational studies and Cochrane criteria for randomized controlled trials (RCTs).

For cancer-related pain, the final sample of five studies involved 482 patients with refractory pain and end-stage disease. Samples ranged from 35–202. Five systematic reviews also were included in the review; however, none of these specifically addressed cancer-related pain.

Overall, moderate quality level evidence was found with cancer-related pain. Three out of five of the studies showed 30% or greater pain relief at three months, and four out of five studies showed 50% or greater pain relief at three months. All studies showed improvement in both nociceptive and neuropathic pain control. Studies showed reduced complications with opioids. Complications occurred related to devices, the surgical implant procedure, or other procedure-related aspects in three studies. In one study, miscalculation of pump refill dates resulted in severe pain among five patients.

Long-term efficacy and safety of the intrathecal approach in terminal cancer is justified, and data supports the use of chronic intrathecal morphine for treatment of intractable malignant pain. Problems and complications can occur. Device-related complications and the need for surgical revision appear to have occurred at higher rates in earlier studies compared to more recent studies, which reflects ongoing improvements in techniques and education. Initial assessments of cost effectiveness suggest that cost savings are achieved after two years in comparison to systemic therapy in noncancer pain.

Patient selection and experience with implanted devices are important considerations in decision making for use of intrathecal pain management. Patient and caregiver self-care education is key to the safety and efficacy of this approach.