PubMed1999
The pharmacologic tailoring guidelines of the World Health Organization represent the accepted treatment algorithm for the management of cancer-related pain syndromes. Unfortunately, the guidelines are only effective in 70% to 90% of patients, leaving a substantial population with intractable pain. In fact, recent surveys have shown that, in the United States, only 50% of hospitalized terminally ill patients die comfortably. When patients do not respond to the WHO guidelines, practitioners should abandon the therapy and not the patient. Interventional pain management approaches including intraspinal delivery of analgesics may be an effective alternative. Before a more permanent system for intraspinal therapy is implemented, a trial must be performed to assure efficacy, rule out toxicity, and establish that the positive response to the intrathecal agent trialed is not due to placebo effects. An external drug delivery system is appropriate if the patient has less than 3 months to live. If the patient is expected to survive more than 3 months, a totally implanted system is appropriate and cost-effective. Although morphine remains the gold standard for intrathecal pain therapy, other opioids such as fentanyl, hydromorphone, sufentanil, and meperidine are now being used in patients who do not tolerate morphine. Nonopioid agents for intrathecal use in patients who have pain syndromes that are poorly responsive to opioids include local anesthetics, such as bupivacaine, and clonidine.