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Acute normovolemic hemodilution is a safe technique for minimizing operative blood loss during major tumor resection in children. Based on our experience using hemodilution anesthesia in 14 successful extensive tumor resections, we conclude the following: (1) this is an effective means of reducing use of bank blood and thus avoiding the risks of multiple transfusions; (2) it facilitates surgical dissection due to increased visibility with dilute blood, and decreased bleeding due to controlled hypotension; (3) this technique is acceptable for Jehovah's Witnesses; (4) hetastarch is an effective, inexpensive colloid hemodiluent which minimized perioperative edema compared to crystalloid hemodilution.  相似文献   
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Summary Protein deficiency was produced by freely feeding young rats a 1% lactalbumin diet for 12 weeks in order to study the effects of protein-calorie malnutrition on skeletal development. During the experiment the food and caloric intake and weight of the experimental animals decreased, while those parameters of the control animals progressively increased. However, when gross caloric intake was expressed as a function of the metabolic size of the animal, the caloric consumption was similar for both groups of animals. The protein-deficient animals exhibited micro-radiographic and histological features of an abnormal pattern of endochondral bone formation. Appositional bone growth, as determined by the daily appositional rate and the percentage of endosteal surfaces undergoing active bone formation, was significantly decreased in these animals, as was the percentage of periosteal surfaces exhibiting resorption. Both chemical analyses of the whole bone and electron probe microanalysis in the specific area of actively calcifying bone revealed no significant differences between the mineral content of control and protein-deficient animals. This study distinguishes the effects of protein deficiency from that of combined protein-calorie deprivation and demonstrates that the abnormal skeletal development observed was the result of a decrease in the quantity of bone formed rather than an altered mineral content.  相似文献   
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Accurate prediction of mortality upon hospital admission is of great value, both for the sake of patients and appropriate resources’ allocation. A myriad of assessment tools exists for this purpose. The evidence relating to the comparative value of clinical assessment versus established indexes are scarce. We analyzed the accuracy of a senior physician’s clinical assessment in a retrospective cohort of patients in a crude, general patients’ population and later on a propensity matched patients’ population. In one department of internal medicine in a tertiary hospital, of 9891 admitted patients, 973 (10%) were categorized as prone to death in a 6-months’ duration by a senior physician. The risk of death was significantly higher for these patients [73.1% vs 14.1% mortality within 180 days; hazard ratio (HR) = 7.58; confidence intervals (CI) 7.02‐8.19, P < .001]. After accounting for multiple, other patients’ variables associated with increased risk of mortality, the correlation remained significant (HR = 3.25; CI 2.85‐3.71, P < .001). We further performed a propensity matching analysis (a subgroup of 710 patients, subdivided to two groups with 355 patients each): survival rates were as low as 45% for patients categorized as prone to death compared to 78% in patients who weren’t categorized as such (P < .001). Reliance on clinical evaluation, done by an experienced senior physician, is an appropriate tool for mortality prediction upon hospital admission, achieving high accuracy rates.  相似文献   
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Albunex Does Not Increase the Sensitivity of the Lung to Pulsed Ultrasound   总被引:1,自引:0,他引:1  
If cavitation in the vasculature of the lung is the physical mechanism responsible for lung hemorrhage, then addition of cavitation nuclei to the blood should enhance the bioeffect. To test the cavitation hypothesis, the extent of lung hemorrhage in mice injected with the echocontrast agent, Albunex®, was compared to lung hemorrhage in animals injected with saline. Animals were exposed for 5 minutes to 1.1-MHz pulsed ultrasound (10 μs pulse length, 100-Hz pulse repetition frequency) at a peak positive pressure at the surface of the animal of 2 MPa. This exposure is approximately twice the threshold pressure amplitude for lung hemorrhage. Lesion areas did not differ significantly in the two groups of animals and were approximately equal to the lesion area in uninjected mice from an earlier study where acoustic exposures were the same. Neither this study nor a related study of hemolysis in vivo suggests that use of Albunex in echocardiographic procedures increases the risk of bioeffects.  相似文献   
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PurposeTo report and discuss the incidence of severe lower extremity injuries associated with robotic procedures in Trendelenburg with lithotomy position.Design and MethodsA case study method was used to describe three cases of patients who underwent robotically assisted urological procedures in Trendelenburg with lithotomy position and developed serious lower extremities injuries resulting in fasciotomies. Furthermore, a literature review was conducted to evaluate risk factors and possible interventions for the prevention of similar injuries.FindingsCase analysis revealed multifactorial causes, including patient comorbidities, long surgical procedures, and blood pressure decreases below the baseline for more than 30 minutes. The severity of lower extremity injury associated with lithotomy position may be underestimated. The etiology of peripheral nerve injury can be attributed to patient comorbidities, positioning, and surgical conditions. Injury prevention should include careful patient and procedural risk assessment, staff education, and communication strategies.ConclusionsExtreme Trendelenburg with lithotomy position for longer periods can lead to serious lower extremities injuries. Preanesthetic screening and multidisciplinary team discussions for additional precautions for high-risk patients are crucial interventions to decrease incidence and severity of lower extremities injuries.  相似文献   
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Writing for publication is rewarding; it requires specific skills which are identified and explored in this article. Intending authors are encouraged to be systematic in targeting the audience, prepararing the text, and presenting it to a publisher. The differing styles needed for academic articles, book reviews and letters are explored as are the stages in publication.  相似文献   
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