November 4, 1983

Relief of Continuous Chronic Pain by Intraspinal Narcotics Infusion Via an Implanted Reservoir

Author Affiliations

From the Divisions of Anesthesiology (Dr Coombs and Messrs Pageau and Mroz) and Neurosurgery (Drs Saunders and Harbaugh), Department of Surgery, Dartmouth-Hitchcock Medical Center, and the Department of Psychiatry, Dartmouth Medical School (Dr Gaytor), Hanover, NH; the Department of Psychology, Purdue University, Indianapolis (Dr Block); and the Department of Public Health, Boston University School of Public Health (Dr Colton).

JAMA. 1983;250(17):2336-2339. doi:10.1001/jama.1983.03340170062030

Ten patients with intractable pain (five cancer and five nonmalignant) were treated with continuous intraspinal morphine delivered by an implanted continuous infusion system. Both patient groups were evaluated and compared using an identical battery of psychometric examinations administered before and 12 weeks after therapy. The cancer-pain group reported significant reduction in pain on serial visual pain analogue scales at 12 weeks compared with no change in the nonmalignant-pain group reports despite a much lower baseline report in the cancer group. Both groups of patients reduced their oral narcotic requirement significantly during continuous intraspinal morphine infusion. While the cancer patients took more oral narcotic at baseline, at 12 weeks no difference existed in oral intake between the two groups. Both groups required significant serial increases in infused morphine, indicating that spinal opiate receptor tolerance occurs. The results of this study confirm the sustained analgesic efficacy reported earlier in cancer-related pain syndromes, thus supporting further cautious expansion of this therapy within the cancer-related pain population. In contrast, a poor response was seen in the nonmalignant-pain group, consistent with the unsatisfactory responses to many potentially analgetic approaches to chronic nonmalignant pain. We are thus discouraged from further use of this therapy in the patient with chronic nonmalignant pain.

(JAMA 1983;250:2336-2339)