The cortical responses to evoked clinical pain in patients with hip osteoarthritis.

BACKGROUND: Experimental models have been used extensively to evaluate pain using e.g., visual analogue scales or electroencephalography (EEG). Stimulation using tonic pain has been shown to better mimic the unpleasantness of chronic pain, but has mainly been evoked by non-clinical stimuli. This study aims to, evaluate the EEG during clinical pain in patients scheduled for total hip replacement with control and resting conditions. METHODS: The hip scheduled for replacement was moved by the examiner to evoke pain for 30 seconds while recording EEG. The control condition entailed movement of the opposite hip in a similar fashion and holding it for 30 seconds. In addition, EEG was recorded during the resting condition with open eyes. The relative spectral content was calculated from the EEG as well as functional connectivity using phase-lag index for frequency bands delta (1-4Hz), theta (4-8Hz), alpha (8-12Hz) and beta (12-32Hz). A mixed model was used for statistical comparison between the three recording conditions. RESULTS: Spectral content differed between conditions in all bands. Functional connectivity differed in delta and theta frequency bands. Post-hoc analysis revealed differences between the painful and control condition in delta, theta and beta for spectral content. Pain during the hip rotation was correlated to the theta (r = -0.24 P = 0.03) and beta (r = 0.25 P = 0.02) content in the EEG. CONCLUSION: EEG differences during hip movements in the affected and unaffected hip appeared in the spectral beta and theta content. This was correlated to the reported pain perceived, pointing towards pain specific brain activity related to clinical pain.

Current practice of acute pain management in children-a national follow-up survey in Germany.

OBJECTIVES: This study aimed to summarize the current standard practices for acute pain management in children in Germany and the implementation of these procedures. The last survey on acute pain management in children was performed in 1999, highlighting the need for an up to date review. METHODS: A questionnaire was mailed to German departments of anesthesiology (n = 885), asking for structures and processes of acute pain management in children. Results were compared between hospitals with and without an acute pain service and with and without a pediatric department. RESULTS: Of the 407 responding hospitals (response rate of 46%), 342 treated children younger than 14 years. These were considered for analysis. Of the 342 hospitals, 42% contained either a general pediatric department or a department of pediatric surgery, and the majority of the responding hospitals had an acute pain service (83%). Pain intensities were measured at least once per shift in 40% of the institutions, and at least once or twice a day in 27%. Of the institutions, 31% did not document pain scores regularly, without any difference between hospitals with or without a pediatric department. Standard operating procedures for acute pain management existed in 68% of the hospitals, with large differences in content and length. Opioids were administered to children in 85% of the hospitals. Nonopioid analgesics were the first choice baseline analgesics in most hospitals. Peripheral regional and epidural analgesia were performed in children in 18% and 8% of the hospitals, respectively (21%/16% with a paediatric department, 16%/1% without; P < 0.001). CONCLUSION: Current practice of pediatric pain management varied widely and the recommendations of guidelines, like regular pain management, were frequently not met. However, improvements could be observed since 1999, for example, an increase in regular pain measurements (4% vs 67%). Furthermore, pain management in hospitals running a pediatric department had a higher degree of organization, and more sophisticated analgesic techniques.