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71.
Endobronchial ultrasound   总被引:11,自引:0,他引:11  
Sheski FD  Mathur PN 《Chest》2008,133(1):264-270
During flexible fiberoptic bronchoscopy (FB), a solitary pulmonary nodule (SPN) is sampled by means of transbronchial needle aspiration (TBNA), brush, or transbronchial lung biopsy under fluoroscopy; and mediastinal lymph nodes are sampled using "blind" TBNA. Endobronchial ultrasound (EBUS) was developed to help visualize the lesion at the time of biopsy in order to improve the diagnostic yield. METHODS: There are two types of EBUS techniques: using a radial probe (RP) with a rotating transducer at the distal tip, which produces a 360 degrees image to the long axis of the bronchoscope; and using an EBUS bronchoscope with a linear transducer at its distal tip, producing a 50 degrees image parallel to its long axis. RESULTS: In biopsies of SPNs < 2 cm using an RP, EBUS demonstrates a higher diagnostic yield than conventional FB techniques. With mediastinal and hilar nodal stations, except for the subcarina, EBUS shows a higher yield over blind TBNA. The current procedural terminology code for EBUS is 31620, a "ZZZ" code submitted in addition to other performed procedures (31622-31638). In 2007, an estimate of physician Medicare reimbursement for EBUS is $70.49. Reimbursement is locality dependent and based on economic-exchange conversion factors. Incorporating an ultrasound image into the report substantiates the use of this technique. Limitations: The physician must learn ultrasound image interpretation and the EBUS technique, and be skilled in TBNA. Maintaining competency requires frequent performance of EBUS. CONCLUSION: EBUS-directed biopsy improves the yield over conventional FB for SPNs < 2 cm and for most mediastinal or hilar nodal stations. This reduces the need to conduct additional diagnostic procedures.  相似文献   
72.
Hennessy D  Juzwishin K  Yergens D  Noseworthy T  Doig C 《Chest》2005,127(5):1764-1774
An increasing proportion of critically ill patients are elderly (ie, >or= 65 years of age). This poses complex challenges and choices for the management of elderly patients. Outcome following admission to the ICU has been traditionally concerned with mortality. Beyond mortality, outcomes such as functional status and health-related quality of life (HRQOL) have assumed greater importance. This article reviews the literature, published in English from 1990 to December 2003, pertaining to HRQOL and functional status outcomes of elderly patients. Functional status and HRQOL of elderly survivors of ICUs has been underinvestigated. There is no agreement as to the optimal instrument choice, and differences between studies preclude meaningful comparison or pooling of results.  相似文献   
73.
BACKGROUND: The glutathione S-transferase P1 (GSTP1) gene is involved in detoxification of electrophilic substances of tobacco smoke. A polymorphism at nucleotide 315 of this gene alters its enzymatic activity. OBJECTIVE: We analyzed the association between the variability in the GSTP1 gene and impairment in lung function in smokers with and without alpha(1)-antitrypsin (AAT) deficiency and COPD.Population and method: The study population consisted of 99 patients with smoking-related COPD and 69 patients with AAT deficiency; 198 healthy volunteers provided the frequency of the different polymorphisms in the general population. GSTP1 genotyping was performed by a real-time polymerase chain reaction amplification assay. RESULTS: The frequency (0.28) of the 105Val polymorphism was identical in COPD patients and the general population. However, the frequency was significantly increased (0.44) in patients with AAT deficiency (odds ratio [OR], 2.09; 95% confidence interval [CI], 1.17 to 3.72 compared to control subjects; and OR, 2.41; 95% CI, 1.27 to 4.59 compared to COPD). FEV(1) percentage of predicted was significantly impaired in AAT-deficient carriers of 105Val. This effect was not observed in COPD patients. CONCLUSIONS: These findings suggest that the frequency of the GSTP1 105Val polymorphism is increased in patients with AAT deficiency. Globally, GSTP1 genotypes, age, and tobacco smoking explained 41% of total FEV(1) percentage of predicted variability in patients with AAT deficiency. The modulatory role of GSTP1 in lung disease has only been observed in smokers lacking AAT.  相似文献   
74.

Background

To determine the most appropriate pancreatic drainage method, by investigating differences in 12-month clinical outcomes in patients implanted with external and internal pancreatic stents as an extension to a previous study on short-term outcome.

Methods

This prospective randomized controlled trial enrolled 213 patients who underwent pancreaticoduodenectomy with duct to mucosa pancreaticojejunostomy between August 2010 and January 2014 (NCT01023594). Of the 185 patients followed-up for 12 months, 97 underwent external and 88 underwent internal stenting. Their long-term clinical outcomes were compared.

Results

Overall late complication rates were similar in the external and internal stent groups (P = 0.621). The percentage of patients with >50% atrophy of the remnant pancreatic volume after 12 months was similar in both groups (P = 0.580). Factors associated with pancreatic exocrine or endocrine function, including stool elastase level (P = 0.571) and rate of new-onset diabetes (P = 0.179), were also comparable. There were no significant between-group differences in quality of life, as evaluated by the EORTC QLQ-C30 and QLQ PAN26 questionnaires.

Conclusion

External and internal stents showed comparable long-term, as well as short-term clinical outcomes, including late complication rates, preservation of pancreatic duct diameters, pancreatic volume changes with functional derangements, and quality of life after surgery.  相似文献   
75.
76.
Human immunodeficiency virus–associated pulmonary arterial hypertension (HIV-PAH) is important to recognize given its association with significant morbidity and mortality. With the introduction of antiretroviral therapy, the focus of disease management has largely shifted from treating immunodeficiency-related opportunistic infections to managing chronic cardiopulmonary complications. Symptoms are nonspecific, and a high index of clinical suspicion is needed to avoid significant delay in the diagnosis of HIV-PAH. Although several viral proteins have been implicated in the pathogenesis of HIV-PAH, the exact mechanism remains uncertain. Further studies are needed to elucidate precise pathogenic mechanisms, early diagnostic tools, and novel therapeutic targets to improve prognosis of this severe complication.  相似文献   
77.
78.
OBJECTIVE: To investigate the long-term development of pulmonary diffusion abnormalities after orthotopic heart transplantation (oHT). DESIGN: Retrospective analysis of pulmonary function test results of different patient groups at different time intervals after oHT was performed. PATIENTS: This investigation included 642 patients who had undergone oHT for chronic heart failure. Patients were grouped according to the time elapsed after transplantation (group 1: n = 164; age, 47 +/- 14 years; days after oHT, 324 +/- 101; group 2: n = 100; age, 48 +/- 15 years; days after oHT, 723 +/- 104; group 3: n = 106; age, 52 +/- 12 years; days after oHT, 1,092 +/- 98; group 4: n = 84; age, 51 +/- 13 years; days after oHT, 1,442 +/- 99; group 5: n = 61; age, 50 +/- 14 years; days after oHT, 1,819 +/- 105; group 6: n = 101; age, 53 +/- 12 years; days after oHT, 2,463 +/- 303; and group 7: n = 26; age, 54 +/- 14 years; days after oHT, 3,478 +/- 246). In 56 (group 8) of the 642 patients, follow-up measurements were performed with tests before and at two time points after oHT (6.5 +/- 1.7 and 12.5 +/- 9.3 months). RESULTS: Of all patients, 39% showed restrictive and obstructive abnormalities with no differences between the groups. No significant differences in lung transfer factor for carbon monoxide (DLCO) were observed (61.2 vs 63.7 vs 65.5 vs 65.6 vs 64.5 vs 65.7 vs 67.6% predicted). Differences in transfer coefficient for carbon monoxide (Kco) were significant between group 1 and 4 (58.7 vs 64.1% predicted), and group 1 and 6 (58.7 vs 63.4% predicted). No differences occurred in the rate with which patients exhibited pathologic abnormalities for DLCO and KCO. After oHT, a marked reduction in diffusion capacity occurred in group 8. On follow-up, these measurements were only slightly restored in terms of the predicted DLCO percentage. No such improvement was observed in KCO or in the rate of pathologic changes for both DLCO and KCO. We conclude, therefore, that the impairment of diffusion does not improve even after a significant period has passed after the oHT. Whether this has any effect on symptoms and/or the prognosis for these patients is extremely unclear.  相似文献   
79.
STUDY OBJECTIVES: Continuing medical education (CME) is meant to bridge the gap between new scientific observations and clinical practice. However, traditional CME has not been effective at altering the behaviors of physicians. One reason for this failure of traditional CME programs may be their inflexibility. In traditional CME, the clinician does not choose the topic, the pace of the program, or the place of learning, and the CME material cannot be easily delivered to the point of care where the clinician needs the information. Computers and computer networks have the potential to accomplish these goals. CME has begun to appear on the Internet; however, there have been few evaluations of its usefulness, acceptance, and effectiveness. Over the last 18 months, we have developed three on-line pulmonary CME programs, and we have delivered them on the Virtual Hospital, the University of Iowa's digital health sciences library on the Internet. We report our initial experience with this CME material. DESIGN: We measured the frequency with which the Internet-delivered CME is accessed by monitoring page accessions and by using a log file analysis program (Analog 1.2.3; University of Cambridge Statistical Laboratory; Cambridge, UK). In addition, we collected all completed CME examinations and evaluation forms submitted by registered users. MEASUREMENTS AND RESULTS: We have found that the frequency with which the Internet-delivered CME is accessed has continued to increase with time (2.3-fold increase over 18 months), that evaluations of technical and content issues are strongly favorable, and that some clinicians have been willing to pay to receive CME through the medium of the Internet. CONCLUSIONS: We feel that with adequate peer review and quality control, physicians will use the Internet-delivered CME. However, several obstacles to wide use remain. These obstacles include issues regarding training in using the Internet for physicians, reluctance of physicians to participate in on-line commerce, and the current unavailability of CME to be delivered in small-grained quantities to the point of care. As these issues are addressed, we feel that on-line CME will represent an increasingly important CME medium for clinicians.  相似文献   
80.
BACKGROUND: The immediate and long-term clinical events associated with the placement and removal of a retrievable filter (ALN filter; ALN Implants Chirurgicaux; Ghisonaccia, France) remain largely unknown. METHODS: This was a prospective cohort study with an 18-month follow-up. All consecutive patients scheduled for placement of an ALN filter between April 1999 and June 2005 in the Radiology Department of our hospital were included. RESULTS: During the study period, placement of an ALN filter was indicated in 220 patients (mean age, 70.8 years), who were followed up for a median duration of 338.5 days (range, 1 to 561 days); 148 patients (67.3%) completed the 18-month follow-up. No patients were unavailable for follow-up. All patients had an acute or past venous thromboembolism. Main indications were recurrent venous thromboembolism despite adequate anticoagulation therapy (10.9%), transient bleeding event (21.8%), definitive contraindication for anticoagulant therapy (26.8%), or obligation to stop anticoagulant therapy due to major surgery, major trauma, or invasive procedure (37.7%). Filter insertion was successful in 98.6% of patients and resulted in an immediate complication in 11.8%. The median duration of filter implantation was 166 days (first to third quartiles, 34 to 478 days). Meanwhile, 17.0% (37 of 217 patients) had at least one venous thromboembolic event. Filter retrieval was attempted in 25.3% of patients after a median of 51 days (range, 6 to 352 days); removal was successful at the first attempt in 92.7% of patients. CONCLUSIONS: The filter could be easily inserted and successfully removed up to 1 year after insertion. Its safety and efficacy in preventing pulmonary embolism should be properly assessed in a randomized study.  相似文献   
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