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1.
Pulmonary hypertension (PH) may complicate idiopathic pulmonary fibrosis (IPF) but the prevalence of PH in IPF remains undefined. The present authors sought to describe the prevalence of PH in IPF. The lung transplant registry for the USA (January 1995 to June 2004) was analysed and IPF patients who had undergone right heart catheterisation (RHC) were identified. PH was defined as a mean pulmonary arterial pressure ((Ppa)) > or =25 mmHg and severe PH as a (Ppa) >40 mmHg. Independent factors associated with PH were determined. Of the 3,457 persons listed, 2,525 (73.0%) had undergone RHC. PH affected 46.1% of subjects; approximately 9% had severe PH. Variables independently associated with mild-to-moderate PH were as follows: need for oxygen, pulmonary capillary wedge pressure (P(pcw)) and forced expiratory volume in one second (FEV(1)). Independent factors related to severe PH included the following: carbon dioxide tension, age, FEV(1), P(pcw), need for oxygen and ethnicity. A sensitivity analysis in subjects with P(pcw) <15 mmHg did not appreciably alter the present findings. Pulmonary hypertension is common in idiopathic pulmonary fibrosis patients awaiting lung transplant, but the elevations in mean pulmonary arterial pressure are moderate. Lung volumes alone do not explain the pulmonary hypertension. Given the prevalence of pulmonary hypertension and its relationship with surrogate markers for quality of life (e.g. activities of daily living), future trials of therapies for this may be warranted.  相似文献   
2.
Multiple options exist for the prevention of deep vein thrombosis (DVT) in medical inpatients. We sought to determine the cost-effectiveness of low-molecular-weight heparin (LMWH) relative to unfractionated heparin (UFH) for DVT prevention in this setting. We conducted a cost-effectiveness analysis from the perspective of a third-party payer employing a decision model and literature-based estimates for inputs. In the base-case analysis, LMWH had little impact on the rate of DVT. Despite higher acquisition costs, however, LMWHs resulted in net savings. Routine use of LMWH saves approximately US$89 per patient. The lower rate of heparin-induced thrombocytopenia (HIT) with LMWH accounted for this differential. Univariate sensitivity analysis revealed the model was moderately sensitive to the odds ratio of HIT with LMWH and the cost of HIT. Multivariate sensitivity analysis confirmed the LMWH approach dominated financially. 'Worst-case' scenario modeling, where LMWH actually increased the risk for DVT, had little effect on the rate of HIT, and was substantially more costly than UFH, still demonstrated that LMWHs were economically superior. Monte-Carlo simulation indicated the 95% confidence interval around the estimate for savings with LMWH ranged from US$7 to US$373. We conclude that, despite their higher cost, LMWHs for thromboprophylaxis in medical patients result in savings.  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
5.
Blunt thoracic trauma. Analysis of 515 patients.   总被引:6,自引:1,他引:5       下载免费PDF全文
A retrospective analysis of 515 cases of blunt chest trauma is presented. The overall thoracic morbidity rate was 36% and mortality rate was 15.5%. Atelectasis was the most common complication. Severe chest trauma can be present in the absence of rib or other thoracic bony fractures. Emergency thoracotomies for resuscitation of the patient with blunt chest trauma with absent vital signs proved unsuccessful in 39 of 39 patients. A high index of suspicion for blunt chest injury occurring in blunt trauma, coupled with an aggressive diagnostic and therapeutic approach, remains the cornerstone of treatment to minimize the morbidity and mortality of such injuries.  相似文献   
6.
The treatment of patients with anterior abdominal stab wounds remains controversial. We reserve celiotomy for patients who have clinical findings of peritonitis or hemorrhage. Repeated physical examination is the most important element of observation. Recently, 330 patients with stable abdominal stab wounds presented over a 12-month period. These patients were followed up with serial physical examinations and laboratory measurements. Of the 330 patients, 107 patients (32%) required celiotomy for the repair of a life-threatening injury (group 1); 28 patients (8%) underwent nontherapeutic celiotomies (group 2); 19 patients (6%) had negative explorations (group 3); and 176 patients (53%) were observed and discharged (group 4). There were three missed injuries in group 4. Serial physical examination can be a reliable technique in the management of abdominal stab wounds and is comparable to other approaches.  相似文献   
7.
Shared care: a review of the literature   总被引:7,自引:1,他引:6  
This review examines broad issues of concern regarding the primary/secondarycare interface. The main purpose was to identify areas of goodpractice which could be adapted for more general use. One ofthe most fundamental aspects identified was communication, whichis discussed in some detail. Also covered are shared prescribingand disease management. The data suggest that the most effectivesystem(s) of shared care has yet to be established. Furtherqualitative and economic evaluations are required, taking intoaccount patient preferences. Although the literature does describecertain practice exemplars, it is clear that inter- and intra-professionalcommunication continues to be a problem. Whilst informationtechnology may provide some of the solutions, it is concludedthat a culture change, which compels health professionals tomake sharing of patient information a much higher priority,is reauired. Keywords. Shared care, seamless care, hospital, general practice, family practice.  相似文献   
8.
Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.  相似文献   
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