Use of Intraspinal Infusion Therapy with Non-Cancer Pain Patients: Follow-up and Comparison of Worker's Compensation...

Objective. This study examines, in a retrospective fashion, the effects of intraspinal infusion therapy in 36 patients with pain of non-cancer origin. In those cases where pain was recalcitrant to the infused opiate and/or had a neuropathic component, a local anesthetic, tetracaine, was added. Patients were followed for a minimum of 16 months (average 20.17 months). Data were collected from the patient, office records, and significant others regarding changes in pain, functioning, work, and oral narcotic use. Telephone interviews were conducted by a disinterested third party. A comparison of worker's compensation (WC) and non-worker's compensation (NWC) patients was made. Results. An average of 60.8% subjective improvement in pain and a 76.7% decrease in use of oral medications were shown. The average reported percentage improvement in functioning was 47.8%. Over 83% of patients rated the outcome of intraspinal infusion therapy as "good or excellent," but only 59.4% of significant others did so. No statistically significant differences were observed between the WC and NWC groups on 10 of 11 dependent variables, with the exception of change in functioning. The addition of tetracaine did not decrease the opiate requirement but appeared to contribute to analgesia. Nausea was the single most drug-related complaint. Twelve patients (33%) encountered catheter complications requiring surgical intervention. Three patients had the drug administration system (DAS) removed for a variety of reasons. There were no documented mechanical failures. Conclusion. The results support the potential utility of infusion therapy in the treatment of non-cancer pain. This treatment, however, is not without problems and should be applied judiciously and in the context of evolving guidelines.