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Epidural sufentanil infusions are routinely used for post-operative analgesia after high-abdominal and thoracic surgery in our hospital. The erroneous administration of a bolus of 250 micrograms of sufentanil epidurally was followed by a 24 hour episode of deep analgesia and respiratory depression. The recovery from respiratory depression over a 27 hour period is described.  相似文献   
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The effective dose equivalent to the operator in intra-oral dental radiography has been determined. The exposure from a bitewing radiograph and periapical views of the left maxillary incisors and first molar was measured at nine heights and 16 positions, all 1 m from the patient. The effective dose equivalent was determined using data from ICRP 51 (International Commission on Radiological Protection: Data for Use in Protection Against External Radiation). The values presented are related to an exposure of 1 C kg-1 (3876 R) measured free in air at the tube-end. They thus constitute ratios which are not influenced by the sensitivity of the film or other detector used and form standard tables which permit the calculation of the effective dose equivalent in clinical situations.  相似文献   
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High thoracic epidural anesthesia (TEA) is increasingly often used in combination with general anesthesia for major thoracic and abdominal surgery. TEA leads to sympatholysis of cardiac efferences leading to improved myocardial oxygen balance, which is in part due to vasodilation of atherosclerotic coronary vessels. To provide the full benefit of TEA, it is important to extend it as patient-controlled epidural analgesia in the postoperative period. If adequate vascular volume is maintained, hypotension is less frequent after TEA than after lumbar epidural anesthesia. However, in combination with general anesthesia, it may be more frequent and more severe. Treatment of hypotension is sometimes difficult and may require the use of nonadrenergic vasoconstrictors (eg, vasopressin). Copyright © 2000 by W.B. Saunders Company  相似文献   
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We investigated the potential of Cine and 2D Tagged Cardiac Magnetic Resonance (CMR) Imaging to distinguish stunned from necrotic left ventricular (LV) myocardium in the early postischemic phase in an open-chest animal model (N=12). Reversible and permanent occlusion of the LAD coronary artery resulted in global LV dysfunction in both groups without significant differences. LAD perfused segments revealed significant higher values for end systolic wall thickening (ESWT) and percentual systolic wall thickening in animals with stunned myocardium. Analysis of strain parameters showed significant regional differences (maximal principal strain 1, deviation angle ) between postischemic and remote myocardium within both groups, however results were not significantly different comparing animals with stunned myocardium to animals with myocardial necrosis. In conclusion, at rest neither global LV functional nor regional strain parameters derived from Cine and 2D Tagged CMR Imaging can distinguish animals with short-term stunned myocardium from respective animals with necrotic myocardium. Diagnostic value of ESWT is limited due to the spatial resolution of the gradient-echo sequence used.Supported by a grant from the Interdisciplinary Center of Clinical Research (IZKF; B1, BMBF-01KS 9604).  相似文献   
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OBJECTIVE: To determine whether a goal-directed terlipressin infusion increases mean arterial pressure without causing a pulmonary vasopressive effect and whether this response impacts on key parameters of oxygen transport in healthy and endotoxemic sheep. DESIGN AND SETTING: Prospective controlled trial in a university research laboratory. ANIMALS AND INTERVENTIONS: Six conscious adult ewes instrumented for chronic study received terlipressin as titrated infusion started with 10 microg x kg(-1) x h(-1) and increased by 5 microg x kg(-1) x h(-1) every 15 min, either until mean arterial pressure was increased by 15 mmHg from baseline, or a maximum of 40 microg x kg(-1) x h(-1) was given. Following 24 h of recovery sepsis was induced and maintained in the same ewes by a continuous infusion of endotoxin ( Salmonella typhosa, 10 ng x kg(-1) min(-1)). After 16 h of endotoxemia the sheep were again treated with terlipressin. MEASUREMENTS AND RESULTS: Systemic oxygen delivery and consumption were calculated before and after the titration period; hemodynamic parameters were measured every 15 min. The increase in mean arterial pressure was greater during endotoxemia than in healthy controls. In both states terlipressin administration decreased cardiac index and diminished oxygen delivery and consumption. While mean pulmonary arterial pressure remained constant, terlipressin increased the pulmonary vascular resistance index in endotoxemic sheep. CONCLUSIONS: During ovine endotoxemia titrated terlipressin reversed hypotension but impaired the pulmonary circulation. The observed decrease in oxygen delivery may carry the risk of tissue hypoxia especially in sepsis, where oxygen demand is typically increased.  相似文献   
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