We have examined cerebral pressure autoregulation while awake, and during 0.5 and 1.5 MAC of sevoflurane anaesthesia in 10 patients undergoing non-intracranial neurosurgical procedures. All patients received a standardized anaesthetic comprising premedication with temazepam 20 mg orally, a sleep dose of propofol, fentanyl 1 microgram kg-1 and vecuronium 0.1 mg kg-1. After tracheal intubation, the lungs were ventilated with a mixture of air and oxygen to mild hypocapnia. Routine monitors included ECG, continuous and intermittent non-invasive arterial pressure, pulse oximetry and end-tidal capnography. In addition, blood flow velocity (vmca) was measured by insonating the middle cerebral artery transtemporally using a 2-MHz transcranial Doppler probe. Cerebral pressure autoregulation was tested by increasing mean arterial pressure (MAP) by approximately 20 mm Hg using an infusion of phenylephrine and simultaneously recording vmca. The index of autoregulation (IOR) during each period of the study, calculated as the ratio of percentage change in estimated cerebral vascular resistance (CVRe = MAP/vmca) to percentage change in MAP, was compared using ANOVA. vmca during 0.5 and 1.5 MAC of sevoflurane anaesthesia was significantly lower than that while awake (mean 79 (SD 24), 54 (15) and 51 (12) cm s-1, respectively; P < 0.05). There was no significant change in vmca with the increase in MAP while awake, or during 0.5 or 1.5 MAC of sevoflurane anaesthesia and IOR was similar under the three conditions (0.82 (0.11), 0.83 (0.04) and 1.0 (0.03), respectively). We conclude that cerebral pressure autoregulation remained intact during sevoflurane anaesthesia in humans.

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The objective of this study was to analyse the temporal course of the jugular venousarterial gradient of S-100B protein after severe head injury and the correlation between the absolute concentrations of serum S-100B protein and outcome, CT findings, and clinical variables.

Background: The therapeutic spinal facet joint interventions generally used for the treatment of axial spinal pain of facet joint origin are intraarticular facet joint injections, facet joint nerve blocks, and radiofrequency neurotomy. Despite interventional procedures being common as treatment strategies for facet joint pathology, there is a paucity of literature investigating these therapeutic approaches. Systematic reviews assessing the effectiveness of various therapeutic facet joint interventions have shown there to be variable evidence based on the region and the modality of treatment utilized. Overall, the evidence ranges from limited to moderate. Objective: To evaluate and update the clinical utility of therapeutic lumbar, cervical, and thoracic facet joint interventions in managing chronic spinal pain. Study Design: A systematic review of therapeutic lumbar, cervical, and thoracic facet joint interventions for the treatment of chronic spinal pain. Methods: The available literature on lumbar, cervical, and thoracic facet joint interventions in managing chronic spinal pain was reviewed. The quality assessment criteria utilized were the Cochrane Musculoskeletal Review Group criteria and Interventional Pain Management Techniques – Quality Appraisal of Reliability and Risk of Bias Assessment (IPM – QRB) for randomized trials and Interventional Pain Management Techniques – Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM – QRBNR) for observational studies. The level of evidence was classified at 5 levels from Level I to Level V. Data sources included relevant literature identified through searches on PubMed and EMBASE from 1966 through March 2015, and manual searches of the bibliographies of known primary and review articles. Outcome Measures: The primary outcome measure was pain relief (short-term relief = up to 6 months and long-term > 6 months). Secondary outcome measures were improvement in functional status, psychological status, return to work, and reduction in opioid intake consumption. Results: A total of 21 randomized controlled trials meeting appropriate inclusion criteria were assessed in this evaluation. A total of 5 observational studies were assessed. In the lumbar spine, for long-term effectiveness, there is Level II evidence for radiofrequency neurotomy and lumbar facet joint nerve blocks, whereas the evidence is Level III for lumbosacral intraarticular injections. In the cervical spine, for long-term improvement, there is Level II evidence for cervical radiofrequency neurotomy and cervical facet joint nerve blocks, and Level IV evidence for cervical intraarticular injections. In the thoracic spine there is Level II evidence for thoracic facet joint nerve blocks and Level IV evidence for radiofrequency neurotomy for long-term improvement. Limitations: The limitations of this systematic review include an overall paucity of high quality studies and more specifically the lack of investigations related to thoracic facet joint injections. Conclusion: Based on the present assessment for the management of spinal facet joint pain, the evidence for long-term improvement is Level II for lumbar and cervical radiofrequency neurotomy, and therapeutic facet joint nerve blocks in the cervical, thoracic, and lumbar spine; Level III for lumbar intraarticular injections; and Level IV for cervical intraarticular injections and thoracic radiofrequency neurotomy. Key Words: Spinal pain, chronic low back pain, chronic neck pain, chronic thoracic pain, intraarticular facet joint blocks, facet joint nerve blocks, conventional radiofrequency neurotomy, pulsed radiofrequency neurolysis

These consensus guidelines aim to provide an overview of best practice for managing chronic spinal pain reflecting the heterogeneity of low back pain. Most guidelines have covered only one aspect of spinal care and thus have been divisive and potentially worsened the quality of care. Additionally, some of the evidence base is subjective and of poor quality. The British Pain Society low back pain pathway has reached across all disciplines and involved input from patients. It is recognized, however, that there is an urgent need for further good-quality clinical research in this area to underpin future guidelines. Considerable work is still needed to clarify the evidence; however, foundations have been laid with this pathway. Key features include: risk stratification; clarification of intensity of psychological interventions; a logical progression for the management of sciatica; and decision points for considering structural interventions such as spinal injections and surgery.

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Brain oxygenation is currently monitored by using jugular bulb oximetry, which attracts a number of potential artifacts and may not reflect regional changes in oxygenation. We compared this method with measurement of brain tissue oxygenation using a multiparameter sensor inserted into brain tissue. The brain tissue monitor seemed to reflect regional brain oxygenation better than jugular bulb oximetry.

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