Rationale: It is not known if abnormal dynamic respiratory mechanics actually limit exercise in patients with mild chronic obstructive pulmonary disease (COPD). We reasoned that failure to increase peak ventilation and Vt in response to dead space (DS) loading during exercise would indicate true ventilatory limitation to exercise in mild COPD. Objectives: To compare the effects of DS loading during exercise on ventilation, breathing pattern, operating lung volumes, and dyspnea intensity in subjects with mild symptomatic COPD and age- and sex-matched healthy control subjects. Methods: Twenty subjects with Global Initiative for Chronic Obstructive Lung Disease stage I COPD and 20 healthy subjects completed two symptom-limited incremental cycle exercise tests, in randomized order: unloaded control and added DS of 0.6 L. Measurements and Main Results: Peak oxygen uptake and ventilation were significantly lower in COPD than in health by 36% and 41%, respectively. With added DS compared with control, both groups had small decreases in peak work rate and no significant increase in peak ventilation. In health, peak Vt and end-inspiratory lung volume increased significantly with DS. In contrast, the COPD group failed to increase peak end-inspiratory lung volume and had a significantly smaller increase in peak Vt during DS. At 60 W, a 50% smaller increase in Vt (P < 0.001) in response to added DS in COPD compared with health was associated with a greater increase in dyspnea intensity (P = 0.0005). Conclusions: These results show that the respiratory system reached or approached its physiologic limit in mild COPD at a lower peak work rate and ventilation than in healthy participants. Clinical trial registered with www.clinicaltrials.gov (NCT00975403).
BACKGROUND: The lung function of patients with idiopathic pulmonary fibrosis (IPF) has not been characterized in detail.OBJECTIVE: To characterize the heterogeneous physiological abnormalities that exist in patients with IPF during their initial clinical evaluation.METHODS: Lung function tests from 93 patients, performed within six months of the initial diagnosis of IPF, were obtained from a referral pulmonary function laboratory at a tertiary care hospital in Canada. A restrictive pattern was defined as total lung capacity (TLC) <95th percentile of predicted value. Patients with obstructive lung disease, lung cancer, emphysema and other restrictive lung diseases were excluded.RESULTS: On diagnosis, 73% of patients with IPF had a restrictive pattern, with a mean TLC of 72% of predicted. Mean forced vital capacity (FVC) was 71% and 44% of patients had an FVC <95th percentile. Mean diffusing capacity for carbon monoxide (DLco) was 60% and DLco/alveolar volume (VA) 92% of predicted. Increased severity of restriction – based on TLC – was associated with lower DLco (74% of predicted in mild restriction and 39% of predicted in severe restriction) and higher forced expiratory volume in 1 s (FEV1)/FVC ratio (82% of predicted in mild restriction and 90% of predicted in severe restriction) but not with age (76 years in mild restriction and 69 years in severe restriction). Regardless of severity of restriction, the average DLco/VA (≥86% of predicted) remained within normal limits.CONCLUSIONS: One in four patients with IPF had normal TLC and more than one‐half had a normal FVC during initial evaluation. As the severity of the restriction increased, FEV1/FVC increased, DLco decreased but DLco/VA remained normal.
Purpose: To assess the impact of primary surgery, partial and total penectomy, and of inguinal lymphadenectomy on health-related quality of life (HRQoL) and the sexual function of penile cancer patients. Materials and Methods: We invited 15 patients surgically treated for penile cancer in the Regional Hospital of Specialized Medicine of the Yucatan Peninsula between 2012 and 2016 to complete the SF-36 quality of life and International Index of Erectile Function (IIEF-5) sexual function questionnaires. We evaluated the impact of primary surgery type and inguinal lymphadenectomy on the outcome of HRQoL and sexual function. Results: A total of 10 patients (66%) completed the SF-36 questionnaire. Surgery type and extent of resection were overall not associated significantly with worse outcomes on the assessed domains of quality of life. However, men treated with partial penectomy reported significantly more pain (p = 0.0547) than men treated with total penectomy. Similarly, men who underwent lymphadenectomy reported significantly more pain (p = 0.0547) than those who were spared from the procedure due to the primary tumor´s stage and grade. Sexual function was severely affected (IIEF mean = 6.5) in patients treated with partial penectomy. Conclusions: Although partial penectomy and lymphadenectomy were significantly associated with more postoperative pain, no differences were observed in other HRQoL domains. Sexual function was severely affected in patients treated with partial penectomy.