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Introduction: Dynamic hyperinflation is an important target in the treatment of COPD. There is increasing evidence that positive expiratory pressure (PEP) could reduce dynamic hyperinflation during exercise. PEP application through a nasal mask and a flow resistance device might have the potential to be used during daily physical activities as an auxiliary strategy of ventilatory assistance. The aim of this study was to determine the effects of nasal PEP on lung volumes during physical exercise in patients with COPD., Methods: Twenty subjects (mean ± SD age 69.4 ± 6.4 years) with stable mild-to-severe COPD were randomized to undergo physical exercise with nasal PEP breathing, followed by physical exercise with habitual breathing, or vice versa. Physical exercise was induced by a standard 6-min walk test (6 MWT) protocol. PEP was applied by means of a silicone nasal mask loaded with a fixed-orifice flow resistor. Body plethysmography was performed immediately pre-exercise and post-exercise., Results: Differences in mean pre- to post-exercise changes in total lung capacity (-0.63 ± 0.80 L, P = .002), functional residual capacity (-0.48 ± 0.86 L, P = .021), residual volume (-0.56 ± 0.75 L, P = .004), S(pO2) (-1.7 ± 3.4%, P = .041), and 6 MWT distance (-30.8 ± 30.0 m, P = .001) were statistically significant between the experimental and the control interventions., Conclusions: The use of flow-dependent expiratory pressure, applied with a nasal mask and a PEP device, might promote significant reduction of dynamic hyperinflation during walking exercise. Further studies are warranted addressing improvements in endurance performance under regular application of nasal PEP during physical activities.

Pulse transit time (PTT), the interval between ventricular electrical activity and peripheral pulse wave, is assumed to be a surrogate marker for blood pressure (BP) changes. The objective of this study was to analyze PTT and its relation to BP during cardiopulmonary exercise tests (CPET). In 20 patients (mean age 51+/-18.4 years), ECG and finger-photoplethysmography were continuously recorded during routine CPETs. PTT was calculated for each R-wave in the ECG and the steepest slope of the corresponding upstroke in the plethysmogram. For each subject, linear and non-linear regression models were used to assess the relation between PTT and upper-arm oscillometric BP in 9 predefined measuring points including measurements at rest, during exercise and during recovery. Mean systolic BP (sBP) and PTT at rest were 128 mm Hg and 366 ms respectively, 197 mm Hg and 289 ms under maximum exercise, and 128 mm Hg and 371 ms during recovery. Linear regression showed a significant, strong negative correlation between PTT and sBP. The correlation between PTT and diastolic BP was rather weak. Bland-Altman plots of sBP values estimated by the regression functions revealed slightly better limits of agreements for the non-linear model (-10.9 to 10.9 mm Hg) than for the linear model (-13.2 to 13.1 mm Hg). These results indicate that PTT is a good potential surrogate measure for sBP during exercise and could easily be implemented in CPET as an additional parameter of cardiovascular reactivity. A non-linear approach might be more effective in estimating BP than linear regression.

Background: The importance of clinical predictors in the treatment of non-small-cell lung cancer (NSCLC) has increased during the last decade. This retrospective study analyzed the combined patient-level data from two phase II trials that investigated the efficacy and safety of combination chemotherapy with vinorelbine and mitomycin in patients with locally advanced or metastatic NSCLC. The aim of this analysis was to determine if patients' baseline and disease characteristics, including histology, gender, smoking history, and expression of TTF-1, might be potential predictors of outcome., Methods: Response rates, unadjusted survival times, and Cox covariate-adjusted hazard ratios (HRs) were calculated. Results were reported separately for each subgroup in each individual trial and in the pooled data set., Results: A total of 175 patients were included in this analysis. Adjusted HRs for both overall survival (OS) and progression free survival (PFS) favored the nonadenocarcinoma histology subgroup, achieving a statistical significance for OS in the pooled data (n = 175; HR 0.68; 95 % CI 0.49-0.94; p = 0.019). TTF-1-negative immunohistochemistry was associated with a significantly higher response rate (25 vs. 0 %; p = 0.04) and with a nonsignificant advantage in OS (n = 33; HR 1.23; 95 % CI 0.56-2.73; p = 0.608). Gender and smoking history were not strongly related to outcome., Conclusions: The results of this analysis indicate that patients with nonadenocarcinoma histology might get superior benefit from combination chemotherapy with vinorelbine and mitomycin. These results should be confirmed in a prospective study.