Pain
-
Surgery and trauma are recognised as important causes of chronic pain, although their overall contribution has not been systematically studied. This paper reports on the contribution of surgery and trauma to chronic pain among 5130 patients attending 10 outpatient clinics located throughout North Britain. Surgery contributed to pain in 22.5% of patients, and was particularly associated with the development of pain in the abdomen and with anal, perineal and genital pain. ⋯ These findings indicate that it can be unhelpful for pain classification systems to combine surgery and trauma in a single category. The results also point to areas for potentially fruitful research into the aetiology of chronic pain. In particular, studies are needed to identify the operative procedures associated with the development of pain so that preventive measures can be implemented.
-
The objective of this study was to explore the relationship between suicidal ideation, suicidal attempts, depression and chronic abdominal pain in data gathered during a systematic epidemiologic survey, the Hispanic Health and Nutrition Examination Survey of the United States National Centre for Health Statistics. The material comprises data collected between 1982 and 1984 in samples of Hispanic groups in the United States. A sub-sample which initially comprised 5498 subjects had provided answers to questions concerning the thoughts about death, wishes to die, thoughts of committing suicide and suicide attempts, as well as information about complaints of chronic abdominal pain and responses to the Centre for Epidemiologic Studies Depression Scale (CES-D). ⋯ This was particularly evident in the Puerto Rican population of the United States where both rates were much increased compared with other Hispanic citizens. The present data are new, but no conclusion can be drawn concerning causality because they are cross-sectional. They indicate the importance of the link between chronic abdominal pain and depression in this population.
-
Noxious stimulation of the rat's face evokes intense face grooming with face wash strokes almost exclusively directed to the stimulated area (e.g. Clavelou et al., Neurosci. Lett., 14 (1989) 3263-3270). ⋯ Only formalin-injected rats displayed significantly more face grooming activity directed to the affected infraorbital nerve territory than unstimulated control rats. Non-painful sensory disturbances (especially mineral oil application) induced an initial bout of directed face grooming; this response was transient and short-lasting. These observations suggest that directed face grooming can be used as a sign of unilateral facial pain in freely moving rodents; unilateral non-painful facial sensory disturbances do not lead to intense and persistent directed face grooming.
-
Sensory abnormalities and changes in spontaneous behavior were examined after a photochemically induced ischemic lesion of the rat sciatic nerve. Male adult rats were anesthetized and the sciatic nerve was exposed. After the intravenous injection of a photosensitizing dye, erythrosin B, the exposed nerve was irradiated just proximal to the nerve trifurcation with light from an argon laser. ⋯ The incidence and severity of the behavioral changes are clearly dependent on the exposure time and are probably due to, at least in part, a demyelinaton. These results partly confirm previous data using a similar technique and suggest that this may represent a new animal model for peripheral neuropathy of ischemic origin. The advantages of the present model are its good reproducibility and the fact that the nerve injury can be easily quantified and graded.