Pain
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Recent studies suggest that coping strategies play an important role in adjustment to chronic pain. Identification of factors that influence coping could potentially help clinicians facilitate the use of adaptive coping strategies by pain patients. According to social learning theory, self-efficacy beliefs (judgments regarding one's capabilities) and outcome expectancies (judgments regarding the consequences of behaviors) are significant determinants of coping behavior. ⋯ In support of social learning theory, and consistent with research in other areas, the patients' beliefs regarding their capabilities were strongly related to reported coping efforts. Beliefs about the consequences of coping efforts and their interaction with beliefs about capabilities were generally unrelated to coping. These results suggest that treatment should emphasize the actual practice and use of adaptive coping strategies over education about their outcome.
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This study compared pain perception in young male and female subjects, using experimental noxious heat stimuli. During 2 sessions, each of 40 subjects rated the magnitude of 120 heat stimuli, ranging from 45 degrees C to 50 degrees C. The study included a comparison of visual analogue and magnitude matching rating procedures, as well as a test of simulated analgesia, in which the range of stimuli presented during the 2 experimental sessions was shifted by 1 degree C. ⋯ In addition, the data suggest that females discriminate among the painful heat intensities better than males. For example, female subjects showed significant between-session discrimination of noxious heat stimuli, while male subjects did not, and females produced steeper within-session stimulus-response functions than did males. These observed differences in nociceptive discrimination between males and females indicate that the sex-related variation in pain perception is probably related to sensory factors rather than differences in attitude or emotional response.
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The effects of electrical stimulation of cervical vagal afferents (VAS) on the background activity and on the responses of 25 spinothalamic tract (STT) neurons to noxious stimuli were studied in anesthetized rats. Background (spontaneous) activity of 9 (36%) STT neurons was inhibited by all intensities of VAS. 6 (24%) units were facilitated at lesser and inhibited at greater intensities of VAS, 5 (20%) units were only facilitated by all intensities of VAS, and 5 (20%) units were not affected by VAS. ⋯ There were no significant differences in VAS-produced modulatory effects between STT neurons and 16 unidentified lumbar spinal dorsal horn neurons studied under the same conditions. These results reveal that descending facilitatory and inhibitory pathways engaged by activation of vagal afferents modulate rostrally projecting nociceptive transmission neurons in the spinal cord, constituting an important regulatory network for nociception.
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Records of 313 patients who had been treated with spinal morphine via an implanted Port-A-Cath were reviewed. In 284 cases the Port-A-Cath was implanted for epidural delivery of morphine in patients with cancer-related pain. These patients were treated for a mean of 96 (range 1-1215) days. ⋯ Port-A-Caths were also implanted for delivery of spinal morphine in 12 patients with chronic pain which was not related to cancer and which failed to respond to other therapies. These patients were treated for a mean of 155 (range 2-575) days. Port-A-Caths were removed from 7 of these patients, primarily due to infection (2 cases) and inadequate pain relief and pain on injection (2 cases).