1ST EXPERIENCES WITH AN IMPLANTABLE PUMP SYSTEM FOR INTRATHECAL THERAPY OF CHRONIC PAIN

The therapeutic concept of local administration of opioids into the pe rimedullar and cerebrospinal fluid is the result of fundamental studie s concerning the discovery and localization of specific binding sites. These studies provoked considerable clinical interest, because they s uggested a non-destructive and fully reversible method. In our departm ent we have been gathering experience with an implantable pump system for various indications of chronic pain on a sample of 25 patients. Th e first implantation was performed in February 1987 and the latest inc luded in this study in February 1991. The sample of patients consisted of two groups: (A) Chronic non-malignant pain (13 cases), (B) Chronic pain due to cancer (12 cases). We used two different pump devices: th e gas-filled continous infusion pump (Infusaid, Mod.400) in 10 cases a nd the manually tractable micro pump (Cordis) in 15 cases. In 23 cases we decided in favour of an intraventricular drug administration, main ly because of the site of the pain; in each of these a ventricular cat heter was placed in the frontal horn of the lateral ventricle. In the remaining two cases, the catheter was placed intraspinally, the cathet er tip terminating at thoracic segments. Nine of the patients with can cer-related pain experienced from excellent to acceptable pain relief, as did also 10 patients with chronic non-malignant pain. Side effects were rare. Our findings also indicate that, in carefully selected pat ients, both malignant and non-malignant pain may be managed satisfacto rily with this technique.