Latest Articles
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Anesthesia and analgesia · Jan 1998
Meta AnalysisDoes acute normovolemic hemodilution reduce perioperative allogeneic transfusion? A meta-analysis. The International Study of Perioperative Transfusion.
The objective of this study was to systematically review the literature and to statistically summarize the evidence evaluating acute normovolemic hemodilution (ANH). Prospective, randomized, controlled trials of ANH that reported either the proportion of patients exposed to allogeneic blood or the units of allogeneic blood transfused were included. All types and languages of publication were eligible. Of 1573 identified publications, 24 trials (containing a total of 1218 patients) were included in the meta-analysis. When all trials were pooled, ANH reduced the likelihood of exposure to allogeneic blood (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.15, 0.62) and the total units of allogeneic blood transfused (weighted mean difference [WMD] -2.22 U, 95% CI -3.57, -0.86). However, there was marked heterogeneity of the results. In trials using a protocol to guide perioperative transfusion, ANH failed to reduce either the likelihood of transfusion (OR 0.64, 95% CI 0.31, 1.31) or the units administered (WMD -0.25 U, 95% CI -0.60, 0.10). Adverse events were incompletely reported. It is possible that biased experimental design is, in part, responsible for the reported efficacy of this technique. ⋯ after a systematic literature review, 24 randomized trials examining the role of acute normovolemic hemodilution were identified, pooled, and summarized using statistical techniques. Many studies reported an impressive reduction in blood transfused. Closer examination suggests that these reductions in blood exposure may be due to flawed study design.
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Acta neurochirurgica · Jan 1998
Meta AnalysisThe association of tranexamic acid and nimodipine in the pre-operative treatment of ruptured intracranial aneurysms.
In the scope of a late intervention policy on ruptured intracranial aneurysms, on D.+12 on an average, we first used tranexamic acid, at moderate doses: 3 g orally or 1.5 g intravenously per day. We, subsequently, added nimodipine, usually 240 mg orally per day or 2 mg intravenously per hour. The medical treatment consisted of amply sufficient hydration, and in systematic and regular administration of analgesics and sedatives. ⋯ For several reasons, only a retrospective study was possible, to evaluate the results of our antifibrinolytic and calcium-blocking therapies, on rebleeding and pre-operative delayed ischaemia. We compared, therefore, similar cases from the literature, with our own cases, taking into consideration the clinical grades, the days of admission and of intervention, the moment of rebleeding and of delayed pre-operative ischaemia, etc. The following impressions emerge: (1) same effectiveness of moderate doses of tranexamic acid; (2) no increase of pre-operative delayed ischaemic complications, in comparison with patients not receiving antifibrinolytics but nimodipine; (3) important role of a devastating initial bleed and of operative complications; (4) difficulty of avoiding rebleeding at D.0, whatever the therapeutic measures, medical and/or surgical.
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Health Technol Assess · Jan 1998
Meta AnalysisPostoperative analgesia and vomiting, with special reference to day-case surgery: a systematic review.
Day-case surgery is of great value to patients and the health service. It enables many more patients to be treated properly, and faster than before. Newer, less invasive, operative techniques will allow many more procedures to be carried out. There are many elements to successful day-case surgery. Two key components are the effectiveness of the control of pain after the operation, and the effectiveness of measures to minimise postoperative nausea and vomiting. ⋯ Full details of the search strategy are presented in the report. RESULTS - ANALGESIA: The systematic reviews of the literature explored whether different interventions work and, if they do work, how well they work. A number of conclusions can be drawn. RESULTS-ANALGESIA, INEFFECTIVE INTERVENTIONS: There is good evidence that some interventions are ineffective. They include: (1) transcutaneous electrical nerve stimulation in acute postoperative pain; (2) the use of local injections of opioids at sites other than the knee joint; (3) the use of dihydrocodeine, 30 mg, in acute postoperative pain (it is no better than placebo). RESULTS-ANALGESIA, INTERVENTIONS OF DOUBTFUL VALUE: Some interventions may be effective but the size of the effect or the complication of undertaking them confers no measurable benefit over conventional methods. Such interventions include: (1) injecting morphine into the knee joint after surgery: there is a small analgesic benefit which may last for up to 24 hours but there is no clear evidence that the size of the benefit is of any clinical value; (2) manoeuvres to try and anticipate pain by using pre-emptive analgesia; these are no more effective than standard methods; (3) administering non-steroidal anti-inflammatory drugs (NSAIDs) by injection or per rectum in patients who can swallow; this appears to be no more effective than giving NSAIDs by mouth and, indeed, may do more harm than good; (4) administering codeine in single doses; this has poor analgesic efficacy. RESULTS-ANALGESIA, INTERVENTIONS OF PROVEN VALUE: These include a number of oral analgesics including (at standard doses): (1) dextropropoxyphene; (2) tramadol; (3) paracetamol; (4) ibuprofen; (5) diclofenac. Diclofenac and ibuprofen at standard doses give analgesia equivalent to that obtained with 10 mg of intramuscular morphine. Each will provide at least 50% pain relief from a single oral dose in patients with moderate or severe postoperative pain. Paracetamol and codeine combinations also appear to be highly effective, although there is little information on the standard doses used in the UK. The relative effectiveness of these analgesics is compared in an effectiveness 'ladder' which can inform prescribers making choices for individual patients, or planning day-case surgery. Dose-response relationships show that higher doses of ibuprofen may be particularly effective. Topical NSAIDs (applied to the skin) are effective in minor injuries and chronic pain but there is no obvious role for them in day-case surgery. RESULTS-POSTOPERATIVE NAUSEA AND VOMITING: The proportion of patients who may feel nauseated or vomit after surgery is very variable, despite similar operations and anaesthetic techniques. Systematic review can still lead to clear estimations of effectiveness of interventions. Whichever anti-emetic is used, the choice is often between prophylactic use (trying to prevent anyone vomiting) and treating those people who do feel nauseated or who may vomit. Systematic reviews of a number of different anti-emetics show clearly that none of the anti-emetics is sufficiently effective to be used for prophylaxis. (ABSTRACT TRUNCATE
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Acta Anaesthesiol Scand · Jan 1998
Meta Analysis Comparative StudyComparing analgesic efficacy of non-steroidal anti-inflammatory drugs given by different routes in acute and chronic pain: a qualitative systematic review.
To test the evidence for a difference in analgesic efficacy and adverse effects of non-steroidal anti-inflammatory drugs (NSAIDs) given by different routes. ⋯ In renal colic there is evidence that NSAIDs act quickest when given intravenously. This may be clinically relevant. In all other pain conditions there is a lack of evidence of any difference between routes. In pain conditions other than renal colic, there is, therefore, a strong argument to give oral NSAIDs when patients can swallow.
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J. Neurol. Neurosurg. Psychiatr. · Jan 1998
Meta AnalysisProphylactic antiepileptic agents after head injury: a systematic review.
To determine the effectiveness and safety of prophylactic antiepileptic agents in the management of acute traumatic head injury. ⋯ Prophylactic antiepileptic drugs are effective in reducing early seizures, but there is no evidence that treatment with such drugs reduces the occurrence of late seizures, or has any effect on death and neurological disability. Insufficient evidence is available to establish the net benefit of prophylactic treatment at any time after injury.