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In clinical practice, the addition of positive end-expiratory pressure (PEEP) into a standard anesthesia circle circuit decreases the delivered tidal volume (DTV) to a patient. We studied the magnitude of the DTV/PEEP relationship in two commonly used anesthesia systems. In addition, the magnitude of the DTV/PEEP relationship varies with both pulmonary compliance and volume of gas contained in the patient's breathing system between the ventilator and PEEP valve site, and this was also evaluated. Routine monitoring of expired tidal volume should be used whenever PEEP is added to an anesthesia circuit.  相似文献   
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BACKGROUND: Angiographic embolization (AE) is used with increasing frequency as an alternative to surgery for control of intraperitoneal and retroperitoneal bleeding. There are no prospective studies on its efficacy, safety, and indications. PATIENTS: From April 1999 to June 2001, patients with abdominal visceral organ injuries or major pelvic fractures sent for AE were prospectively studied. Patients were transported to the angiography suite either because they were hemodynamically unstable ("emergent" angiography) or hemodynamically stable but had injuries likely to bleed ("preemptive" angiography). The efficacy of AE was derived from its ability to control bleeding radiographically and clinically; the safety of AE was determined by the complications related to transport, vascular access, catheter insertion, contrast administration, and tissue necrosis after interruption of blood supply to organs. Predictors of bleeding were identified by comparing patients who showed contrast extravasation on angiography with those who did not by univariate and multivariate analysis. RESULTS: Of 100 consecutive patients evaluated by angiography for bleeding from major pelvic fractures (n = 65) or solid visceral organ injuries (n = 35), 57 were found to have active contrast extravasation and were embolized, 23 were found to have indirect signs of vascular injury or ongoing hemodynamic instability and were embolized, and 20 had no signs of bleeding and were not embolized. AE was effective and safe in 95% and 94%, respectively, of 80 patients who were embolized. Four patients had recurrent bleeding after AE and five developed AE-related complications. In three of the four patients, bleeding was controlled by repeat AE. In all five patients, the complications were managed with no further sequelae. Three independent factors were predictive of bleeding identified on angiography: age older than 55 years, absence of long-bone fractures, and emergent angiography. The presence of all three independent predictors was associated with a 95% probability of bleeding; however, the probability of bleeding was still 18% when all three independent predictors were absent. CONCLUSION: AE is highly effective in controlling bleeding caused by abdominal and pelvic injuries and difficult to manage by surgery. Older age, the absence of long-bone fractures, and emergent angiography increase the likelihood of finding active bleeding angiographically. However, there are no clinical characteristics to exclude reliably all patients who are not actively bleeding internally. Because of this and its reasonable safety profile, AE should be offered liberally in patients with selected injuries of the pelvis and abdominal visceral organs.  相似文献   
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Speech-controlled generation of radiology reports   总被引:1,自引:0,他引:1  
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.  相似文献   
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The effect of barium on blood in the gastrointestinal tract   总被引:2,自引:0,他引:2  
  相似文献   
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Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs.  相似文献   
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