Articles: hyperalgesia.
-
Remifentanil anesthesia enhances postoperative pain in animals and humans. The authors evaluated the impact of the dose (microg x kg(-1) x min(-1)) and duration of remifentanil infusion, and the effects of a second surgery on postoperative pain sensitization. ⋯ In this model of incisional pain, remifentanil induces pronociceptive effects, which are dose dependent but unaltered by the duration of administration. A second surgery performed on the same site and experimental conditions induces greater postoperative hyperalgesia that is enhanced when remifentanil is used as an anesthetic.
-
Curr Pain Headache Rep · Dec 2009
ReviewEnhanced pain perception in rheumatoid arthritis: novel considerations.
Enhanced pain perception is common among patients with rheumatoid arthritis (RA). Given the putative role of proinflammatory cytokines in the development of hyperalgesia, a greater understanding of factors that facilitate increased cytokine expression in RA stands to increase understanding of the sources of enhanced pain perception. Patients with RA have significantly greater stress-induced proinflammatory cytokine release. ⋯ Parasympathetic insufficiency has also been demonstrated, which may enhance pain perception indirectly through disinhibited cytokine expression. Several psychological variables have also been demonstrated to affect pain perception in patients with RA. Identification of factors that contribute to enhanced pain perception in RA may aid in the development of novel analgesic strategies that, in turn, may decrease disease activity and improve general clinical outcomes.
-
The aim of this study was to investigate tactile sensitivity near the site of primary hyperalgesia evoked by capsaicin applied topically to the dorsolateral aspect of the hand. In the first experiment (N = 15), touch thresholds increased in the fifth finger ipsilateral to the topically applied capsaicin, but remained unchanged at greater distances from the site of capsaicin treatment. In a second experiment (N = 12), the effect of the capsaicin treatment on sensations evoked not only by light touch but also by warmth, heat-pain, and pressure-pain to a 2-mm diameter steel probe was investigated in the fifth finger. ⋯ However, sensitivity to pressure-pain increased in the fifth finger after the capsaicin treatment, possibly due to activation of nociceptors sandwiched between the probe tip and bone that normally responded to sharp stimuli. These findings suggest that the central mechanisms that mediate secondary mechanical hyperalgesia suppress sensitivity to innocuous tactile sensations. This effect may contribute to tactile hypoesthesia in chronic pain conditions.
-
Am J Hosp Palliat Care · Nov 2009
Case ReportsBuprenorphine for neuropathic pain--targeting hyperalgesia.
Opioids are well known to relieve severe, acute, and chronic nociceptive pain, but neuropathic pain shows a relatively poor response to opioids. Buprenorphine, a partial mu and ORL-1-receptor agonist, kappa-delta receptor antagonist, interacts with different G proteins than potent mu agonists and hence is not cross-tolerant to standard opioids. ⋯ We present a patient with neuropathic pain and tactile allodynia in which buprenorphine alleviated the hyperalgesia to a greater extent than pain severity. We found buprenorphine to be effective in reducing hypersensitivity in neuropathic pain when pure mu agonists fail to produce a response or in individuals who are intolerant to pure mu agonists.