Pain
-
Comparative Study
Differences in brain responses to visceral pain between patients with irritable bowel syndrome and ulcerative colitis.
Patients with mild chronic inflammation of the rectum or ileum have reduced perceptual responses to rectosigmoid distension compared to patients with irritable bowel syndrome (IBS). The current study sought to identify differences in regional cerebral blood flow (rCBF) during rectal distension, which might correspond to these perceptual differences. In 8 male ulcerative colitis (UC) patients with quiescent disease, 7 male IBS patients and 7 healthy male controls, rCBF was assessed using 15O-water positron emission tomography at baseline and during actual and anticipated but undelivered rectal distensions. ⋯ According to the connectivity analysis, this effect was mediated by inhibition of medial frontal cortex by the RLFC. Chronic colonic inflammation is not necessarily associated with increased visceral afferent input to the brain during rectal distension. In the sample studied, the primary difference between functional and quiescent inflammatory disease of the colon was in terms of greater activation of limbic/paralimbic circuits in IBS, and inhibition of these circuits in UC and controls by the RLFC.
-
Chronic pain following whiplash injury and non-specific arm pain (NSAP, previously termed diffuse repetitive strain injury) present clinicians with problems of diagnosis and management. In both patient groups there are clinical signs of altered nerve movement and increased nerve trunk mechanosensitivity. Previous studies of NSAP patients have identified altered median nerve movement at the wrist. ⋯ In the whiplash patients the pattern of transverse median nerve movement at the proximal carpal tunnel was significantly different to controls (patient mean=2.57+/-0.80 mm (SEM) in a radial direction; control mean=0.39+/-0.52 mm in an ulnar direction). Signs of neural mechanosensitivity (i.e. painful responses to median nerve trunk and brachial plexus pressure and stretch) were apparent in both patients groups. Change in nerve tension and neural mechanosensitivity may contribute to symptoms in whiplash and NSAP patients.
-
Postoperative pain significantly impacts patient recovery. However, postoperative pain management remains suboptimal, perhaps because treatment strategies are based mainly on studies using inflammatory pain models. We used a recently developed mouse model of incisional pain to investigate peripheral and spinal mechanisms contributing to heat hyperalgesia after incision. ⋯ Finally, heat hyperalgesia after incision was reversed by antagonism of spinal non-NMDA receptors, unlike inflammatory hyperalgesia, which is mediated via NMDA receptors. Thus, TRPV1 is important for the generation of thermal hyperalgesia after incision. Our observations suggest that all experimental pain models may not be equally appropriate to guide the development of postoperative pain therapies.
-
Statistics and prescription database studies show that analgesics are widely utilized, but do not tell anything about either the factors behind analgesic use or how over-the-counter (OTC) analgesics are being used. We aimed to study the prevalence of frequent use of prescribed and OTC analgesics. We also investigated the background factors related to frequent analgesic use and assessed rationality of analgesic usage patterns. ⋯ Low mood and not being employed also increased the probability for daily analgesic use. Frequent analgesic use seems to be common at population level. Concomitant use of both prescribed and OTC analgesics can be considered irrational, as it increases the risk of adverse events.
-
Relative readiness to assume a self-management approach to chronic pain can be conceptualised as a stage model. Although both initial stage (precontemplation, action) and changes in attitudes reflecting stage orientation have been shown to predict treatment outcome, the joint contributions of these factors need to be examined. Sixty-five chronic pain patients, participating in a 4-week multidisciplinary pain program, completed the Pain Stages of Change Questionnaire (PSOCQ), subscales of the Multidimensional Pain Inventory, and the Beck Depression Inventory at pre-, mid- and post-treatment. ⋯ Results showed that: (a) stage group interacted with pre- to mid-treatment Precontemplation subscale changes to predict mid- to late-treatment pain severity and interference changes such that precontemplation attitude decreases were related to reduced pain and interference only among patients who were already action stage at pre-treatment; (b) stage group interacted with pre- to mid-treatment Action subscale changes to predict mid- to late-treatment interference and activity changes such that action attitude increases were related to reduced interference and increased activity only among patients at the action stage at pre-treatment; (c) pre- to mid-treatment decreases in depression did not account for these effects. Results suggest that any advantage enjoyed by patients with predominant action attitudes at pre-treatment may be enhanced by consolidating a pain self-management approach during treatment. In contrast, late-treatment gains of patients initially taking a predominant precontemplation stance were unaffected by their degree of early-treatment attitude changes.