Changes in lower limb muscle function and muscle mass following exercise-based interventions in patients with chronic obstructive pulmonary disease : a review of the English-language literature

Chronic obstructive pulmonary disease (COPD) patients often experience lower limb muscle dysfunction and wasting. Exercise-based training has potential to improve muscle function and mass, but literature on this topic is extensive and heterogeneous including numerous interventions and outcomemeasures. This reviewuses a detailed systematic approach to investigate the effect of this wide range of exercise-based interventions on muscle function and mass. PUBMED and PEDro databases were searched. In all, 70 studies (n = 2504 COPD patients) that implemented an exercise-based intervention and reported muscle strength, endurance, or mass in clinically stable COPD patients were critically appraised. Aerobic and/or resistance training, high-intensity interval training, electrical or magnetic muscle stimulation, whole-body vibration, andwater-based training were investigated. Muscle strength increased in 78%, muscle endurance in 92%, and muscle mass in 88% of the cases where that specific outcome was measured. Despite large heterogeneity in exercise-based interventions and outcome measures used, most exercise-based trials showed improvements in muscle strength, endurance, and mass in COPD patients. Which intervention(s) is (are) best for which subgroup of patients remains currently unknown. Furthermore, this literature review identifies gaps in the current knowledge and generates recommendations for future research to enhance our knowledge on exercise-based interventions in COPD patients

Accepting or declining dialysis: considerations taken into account by elderly patients with end-stage renal disease

BACKGROUND: Elderly patients with end-stage renal disease have to make a difficult decision whether or not to start dialysis. This study explores the considerations taken into account by these patients in decision-making regarding renal replacement therapy. METHOD: In-depth interviews were conducted to gain an enhanced understanding of the considerations in treatment decision-making. Fourteen patients aged 65 years or older participated in the interviews, of whom 8 patients had made the decision to start, and 6 patients the decision to decline, dialysis. RESULTS: All participating patients had a variety of health problems, but appeared to have normal cognitive functions. Patients who declined dialysis were older and more often men and widow(er)s compared with patients who accepted dialysis. Patients chose to start dialysis because they enjoyed life, were not prepared to face the end of life, felt they had no other choice or had care-giving responsibilities for family members. Patients declined dialysis because of the speculated loss of autonomy, their age-associated decrease in vitality, distance from dialysis center and reluctance to think about the future. CONCLUSION: Results suggest that patients' decisions to decline or accept dialysis are not based on the effectiveness of the treatment, but rather on personal values, beliefs and feelings toward life, suffering and death, and the expected difficulties in fitting the treatment into their life

Determinants of polypharmacy and compliance with GOLD guidelines in patients with chronic obstructive pulmonary disease

BACKGROUND: Polypharmacy of respiratory medications is commonly observed in patients with chronic obstructive pulmonary disease (COPD). The aims of this study were to investigate determinants of polypharmacy and to study the consistency of actual respiratory drug use with current Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines in pulmonary rehabilitation candidates with COPD. METHODS: Data were extracted from the records of all patients with a diagnosis of COPD referred for pulmonary rehabilitation to CIRO+ between 2005 and 2009. Use of respiratory medications, self-reported COPD exacerbations, lung function, blood gases, exercise capacity, Medical Research Council (MRC) dyspnea grade, and St George's Respiratory Questionnaire (SGRQ) were recorded as part of assessment of health status. RESULTS: In total, 1859 COPD patients of mean age (+/- standard deviation) 64.3 +/- 9.7 years and with a forced expiratory volume in one second (FEV(1)) of 44.7% +/- 18.2% were included. On average, patients used 3.5 +/- 1.5 respiratory medications; this number increased with increasing GOLD stage, MRC score, and SGRQ scores. FEV(1) (% predicted), SGRQ, and number of recent exacerbations were independent determinants of polypharmacy. Use of long-acting bronchodilators and inhaled corticosteroids was substantial and comparable in all GOLD stages. Use of corticosteroids was not restricted to patients with frequent exacerbations. CONCLUSION: Polypharmacy of respiratory medications is common in COPD patients with persistent symptoms. In addition to severity of disease, health status is an independent predictor of polypharmacy. Actual drug use in COPD patients referred for pulmonary rehabilitation is partially inconsistent with current GOLD guidelines

Theory and particle tracking simulations of a resonant radiofrequency deflection cavity in TM110_{110} mode for ultrafast electron microscopy

We present a theoretical description of resonant radiofrequency (RF) deflecting cavities in TM$_{110}$ mode as dynamic optical elements for ultrafast electron microscopy. We first derive the optical transfer matrix of an ideal pillbox cavity and use a Courant-Snyder formalism to calculate the 6D phase space propagation of a Gaussian electron distribution through the cavity. We derive closed, analytic expressions for the increase in transverse emittance and energy spread of the electron distribution. We demonstrate that for the special case of a beam focused in the center of the cavity, the low emittance and low energy spread of a high quality beam can be maintained, which allows high-repetition rate, ultrafast electron microscopy with 100 fs temporal resolution combined with the atomic resolution of a high-end TEM. This is confirmed by charged particle tracking simulations using a realistic cavity geometry, including fringe fields at the cavity entrance and exit apertures