Chronic Nonmalignant Pain
Goal of Therapy
45. W.C., a 38-year-old man, has been disabled for the past 2 years because of an injury to his cervical spine sustained while operating a forklift at a warehouse. He is currently taking oral oxycodone 5 mg with acetaminophen 325 mg (Percocet) two tablets QID as needed for severe pain, codeine 30 mg with acetaminophen 325 mg (Tylenol #3) or hydrocodone 5 mg with acetaminophen 325 mg (Lorcet-5) two tablets QID as needed for less severe pain, and diazepam 10 mg TID for neck spasms. W.C. describes the pain as sharp and stabbing, and the spasms in his neck are his most troublesome problem. The spasms become severe if he stops taking the diazepam, and the pain starts to build 2 hours after taking the opioids. W.C. currently is seeing an internist and an orthopedic surgeon who prescribed his analgesics. W.C. also has undergone several cervical discectomies and vertebral fusion with minimal pain relief. What are the treatment goals in W.C.?
Opioid use for chronic nonmalignant pain remains the most controversial issue facing clinical pain management. Not only is opioid efficacy subject to debate, but, in addition, the potential for opioid dependency creates considerable hesitation on the part of many prescribers.153,154 Although neuropathic pain may respond to opioids, high dosages are often needed.155 Opioid analgesics should be considered only after the patient has received and failed adequate trials of an NSAID or other analgesic agents. In addition, patients should be evaluated for physical interventions, such as muscle strengthening or conditioning exercises that may improve their clinical situation, before becoming over-reliant on opioids for pain management. As with any chronic pain management, time-contingent dosing (fixed dose and interval) is superior to as-needed dosing. If an opioid is used to manage chronic pain, a longer-acting agent (e.g., SR morphine, methadone, levorphanol) should be used to minimize fluctuations in serum concentrations. Patients should be monitored closely for both efficacy and toxicity.
Shorter-acting opioid analgesics often can complicate chronic nonmalignant pain management by exacerbating the pain perception because of fluctuating serum concentrations and the production of opioid withdrawal hyperalgesia when serum concentrations are low. Analogous withdrawal effects can occur with sedative-hypnotics and antispasmodics as well, particularly those with relatively short half-lives.
Before any therapeutic modality is initiated, the primary caregiver and the patient must have a written agreement that includes provisions for a single prescriber; monitoring of serum drug concentrations; urine or blood substance abuse screening; as well as an agreement to inform all current and future health care providers regarding pain management, and termination of service. There should be only one prescriber for all of W.C.'s medications, and all of his health care providers must be informed of the therapeutic plans. The immediate goal of pain management for W.C. is to consolidate his analgesic regimen to a time-contingent, longer-acting opioid. Longer-term goals should include withdrawal of diazepam, consideration of opioid withdrawal, and institution of alternative analgesic adjuncts (antidepressants or membrane stabilizers). Psychological evaluation and support should supplement pharmacologic therapy. The overall therapeutic goal for W.C. is pain control and pain reduction, but not total pain elimination. He should be able to conduct activities of daily life with minimal discomfort, and ideally be able to return to gainful employment in some capacity, even if his work duties are modified.
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