Pains Revisited.

OBJECTIVES: The management of pain patients has not evolved as rapidly as envisioned when IASP was founded almost 50 years ago. We sought to identify factors that could contribute to this situation, with a focus on concepts of pain and the education of pain physicians. METHODS: Relevant literature describing new strategies for diagnosing and managing patients with high-impact chronic pain was reviewed. RESULTS: It appears that the acute-chronic dichotomy has outlived its usefulness and pains should be identified as of peripheral origin or due to central processing errors. Pains of peripheral origin and those of central processing errors require different diagnostic and therapeutic strategies. DISCUSSION: Peripheral treatments and opioids are not effective for central pains. When the cause of the pain lies in the central nervous system, a more centrally focused approach is needed to minimize wasteful pursuit of peripheral causes. The education and training of pain physicians should reflect the skills needed to address these 2 very different clinical problems.

Opioid analgesics for nociceptive cancer pain: A comprehensive review.

Pain is one of the most burdensome symptoms in people with cancer, and opioid analgesics are considered the mainstay of cancer pain management. For this review, the authors evaluated the efficacy and toxicities of opioid analgesics compared with placebo, other opioids, nonopioid analgesics, and nonpharmacologic treatments for background cancer pain (continuous and relatively constant pain present at rest), and breakthrough cancer pain (transient exacerbation of pain despite stable and adequately controlled background pain). They found a paucity of placebo-controlled trials for background cancer pain, although tapentadol or codeine may be more efficacious than placebo (moderate-certainty to low-certainty evidence). Nonsteroidal anti-inflammatory drugs including aspirin, piroxicam, diclofenac, ketorolac, and the antidepressant medicine imipramine, may be at least as efficacious as opioids for moderate-to-severe background cancer pain. For breakthrough cancer pain, oral transmucosal, buccal, sublingual, or intranasal fentanyl preparations were identified as more efficacious than placebo but were more commonly associated with toxicities, including constipation and nausea. Despite being recommended worldwide for the treatment of cancer pain, morphine was generally not superior to other opioids, nor did it have a more favorable toxicity profile. The interpretation of study results, however, was complicated by the heterogeneity in the study populations evaluated. Given the limited quality and quantity of research, there is a need to reappraise the clinical utility of opioids in people with cancer pain, particularly those who are not at the end of life, and to further explore the effects of opioids on immune system function and quality of life in these individuals.