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Alterations in pulmonary vessel structure and function are highly prevalent in patients with COPD. Vascular abnormalities impair gas exchange and may result in pulmonary hypertension, which is one of the principal factors associated with reduced survival in COPD patients. Changes in pulmonary circulation have been identified at initial disease stages, providing new insight into their pathogenesis. Endothelial cell damage and dysfunction produced by the effects of cigarette smoke products or inflammatory elements is now considered to be the primary alteration that initiates the sequence of events resulting in pulmonary hypertension. Cellular and molecular mechanisms involved in this process are being extensively investigated. Progress in the understanding of the pathobiology of pulmonary hypertension associated with COPD may provide the basis for a new therapeutic approach addressed to correct the imbalance between endothelium-derived vasoactive agents. The safety and efficacy of endothelium-targeted therapy in COPD-associated pulmonary hypertension warrants further investigation in randomized clinical trials. [ABSTRACT FROM AUTHOR]

STUDY OBJECTIVES: In patients with moderate-to-severe COPD, an encouraged 6-min walking test (6MWT) is a high-intensity submaximal exercise protocol that shows an oxygen uptake (Vo(2)) plateau after the third minute of the test. This last feature prompted the hypothesis that self-paced walking speed is set to achieve 'maximal' sustainable Vo(2), namely 'critical power' or 'critical speed.' PATIENTS AND METHODS: Eight patients with moderate-to-severe COPD (mean age, 68 +/- 7 years [+/- SD]; FEV(1), 50 +/- 13% predicted; Pao(2), 69 +/- 8 mm Hg) underwent the following tests on different days in order: (1) encouraged 6MWT; (2) standard incremental shuttle test to identify peak walking speed; (3) four different high-intensity, constant walking speed tests to exhaustion to calculate critical walking speed; and (4) timed walking test at critical walking speed (CWS) to examine sustainability of the exercise. RESULTS: 6MWT and CWS showed similar results (mean of last 3 min): Vo(2) (1,605 +/- 304 mL/min vs 1,584 +/- 319 mL/min), minute ventilation (47 +/- 12 L/min vs 48 +/- 11 L/min), respiratory exchange ratio (0.89 +/- 0.1 vs 0.90 +/- 0.1), heart rate (130 +/- 18 beats/min vs 131 +/- 16 beats/min), Borg dyspnea score (5.4 +/- 1.3 vs 5.5 +/- 2.4), and walking speed (1.49 +/- 0.1 m/s vs 1.44 +/- 0.1 m/s, respectively). CONCLUSION: This study supports that 6MWT indicates maximum sustainable exercise that might be related with its predictive value in COPD patients. [ABSTRACT FROM AUTHOR]

Study Objectives: To evaluate the intraoperative evolution of patients with COPD during lung resection and to test whether exercise testing could be helpful in the prediction of the intraoperative course.Design: Prospective study.Setting: University teaching hospital.Patients: Forty patients (mean [+/- SD] age, 65 +/- 9 years) with COPD (ie, FEV(1), 55 +/- 11% of predicted) and resectable lung neoplasms.Interventions: Preoperatively, pulmonary function testing, quantitative lung perfusion scanning, and exercise performance testing were administered. Intraoperatively, pulmonary, hemodynamic, and blood gas measurements were performed at five stages, including periods of two-lung ventilation (TLV) and periods of one-lung ventilation (OLV).Results: During OLV, compared with TLV, the PaO(2)/fraction of inspired oxygen (FIO(2)) ratio decreased from 458 +/- 120 to 248 +/- 131 mm Hg (p < 0.05), whereas pulmonary artery pressure (PAP) increased from 18 +/- 5 to 23 +/- 5 mm Hg (p < 0.05). Cardiac output (t) also increased from 4.0 +/- 1.2 to 5.1 +/- 1.9 L/min (p < 0.05), yielding to a higher mixed venous PO(2). Both PaO(2) and t during OLV were significantly lower in patients who had undergone right thoracotomies compared with those who had undergone left thoracotomies. The PaO(2)/FIO(2) ratio during OLV correlated with the PaO(2) during exercise (r = 0.39; p = 0.01) and with the perfusion of the non-neoplastic lung (r = 0.44; p = 0.005).Conclusions: In COPD patients, OLV leads to a significant derangement of gas exchange, which is more pronounced in right thoracotomies. Preoperative measurement of PaO(2) during exercise and the distribution of perfusion by lung scan might be useful to identify those patients who are at the greatest risk of abnormal gas exchange during lung resections. [ABSTRACT FROM AUTHOR]

A 51-year-old woman was given a diagnosis of primary retroperitoneal synovial sarcoma, which was surgically removed, and she was subsequently treated with chemotherapy and radiotherapy. Five years later, the patient was readmitted with a 1-month history of progressive dyspnea and was initially given a diagnosis of bilateral pulmonary embolism. Angiography performed some time later revealed progression of the previous filling defects and the appearance of two new nodular endovascular images. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) was performed, and the cytologic analysis of the cell aspirate was compatible with endovascular metastatic sarcoma. In conclusion, EBUS-TBNA in the appropriate setting is an effective method for sampling endovascular lesions, adding pathologic information and allowing for early and accurate diagnosis. [ABSTRACT FROM AUTHOR]