TI - Decision-making in the opioid therapy of cancer pain: interim analysis of a prospective survey

(Meeting abstract)

AB - Sequential trials of opioid drugs or routes of administration are frequently required to optimize the balance between analgesia and adverse effects. Neither the clinical factors that determine the choice of drug or route nor the variability in patient (pt) response have been studied previously. To assess these phenomena, we are evaluating pts referred to the Pain Service using a new instrument completed by the treating physician that records reason(s) for referral, pain-related data, and reason(s) for change(s) in analgesic regimen. To date, 25 consecutive pts with advanced cancer (11 males and 14 females; median age 51 yr, range 31-82) have been followed until discharge (n=23) or death (n=2). The reason(s) for referral included uncontrolled pain despite analgesic therapy (68%), difficulties in pain assessment (33%), and analgesic toxicity with inadequate (33%) or adequate (11%) analgesia. All pts had received previous opioid trials (median 3, range 1-6). Following referral, a total of 45 changes in either drug, route, or both were evaluable. Two pts died and 13 were discharged during the initial therapeutic trial. Ten required additional trials to achieve an acceptable balance between pain relief and adverse effects: 5 required 2 trials, 2 required 3 trials, and 3 required 4 or more sequential trials. The major factors that influenced opioid selection were previously well tolerated (48%), no known prior dose-limiting toxicity (51%), and easy to titrate (56%).

Convenience of formulations (24%) was associated only with the selection of morphine, whereas concerns regarding renal function (8%) and drug metabolites (14%) were associated with the selection of hydromorphone. The major reasons for the choice of a parenteral rather than oral route were the need for very rapid analgesic effect (66%), inability to swallow (31%), impaired intestinal function (25%) and intolerance of po administered drugs (18%). In the 2 cases in which spinal route was selected, dose- limiting toxicity with systemic administration was the compelling consideration. In 6 cases, an initial parenteral route was changed to the oral route prior to discharge; the need for rapid analgesic effect was a reason for the first selection, and resolution of that need and improved convenience were the reasons for the change. This interim analysis illustrates (1) the large variability in response to different opioids and routes of administration; (2) the potential utility of sequential therapeutic trials; and (3) the likely existence of trends in the rationale for the selection of opioid therapies, enhanced understanding of which may improve therapeutic decision making AD - Pain Service AD - Dept. of Neurology AD - Memorial Sloan-Kettering Cancer Center AD - New York AD - NY 10021 UI - 93695900

SO - Proc Annu Meet Am Soc Clin Oncol 1993;12:A1502-A150