Use of supplemental oxygen during exercise testing and training for people with chronic obstructive pulmonary disease: a survey of Australian pulmonary rehabilitation programs.

OBJECTIVES: The aims of this study were to determine, in Australian pulmonary rehabilitation programs for people with COPD: (1) whether oxygen saturation (SpO2) was monitored during exercise testing; (2) whether supplemental oxygen was available during exercise testing and/or training; (3) whether oxygen was prescribed during exercise training; and the reason for providing oxygen; (4) whether a protocol was available for supplemental oxygen prescription during exercise training. METHODS: This was a cross-sectional multi-center study using a purposed-designed survey. De-identified survey data were analyzed and the absolute number and percentage of responses were recorded for each question. RESULTS: The survey was sent to 261 pulmonary rehabilitation programs and 142 surveys (54%) were available for analysis. Oxygen saturation was monitored during exercise testing in 92% of programs. Supplemental oxygen was available in the majority of programs during exercise testing (82%) and training (84%). The rationale cited by 87 programs (73%) for prescribing oxygen during exercise training was maintaining SpO2 above a threshold ranging from SpO2 80-88%. Forty-five (32%) programs had a protocol for oxygen prescription during exercise training. CONCLUSION: While monitoring of SpO2 during exercise testing and using supplemental oxygen during testing and training is common in Australian pulmonary rehabilitation programs, few programs had a protocol in place for the prescription of supplemental oxygen for people with COPD who were not on long-term oxygen therapy. This may be due to lack of strong evidence to support the use of supplemental oxygen during exercise training.

Impaired exercise capacity after lung transplantation is related to delayed recovery of muscle strength.

Lung transplant recipients report reduced exercise capacity despite satisfactory graft function. We analysed changes in lung function, six-min walk distance (6MWD), and quadriceps strength in the first 26-wk post-transplant and examined what factors predict 6MWD recovery. All lung transplant recipients at a single institution between June 2007 and January 2011 were considered for inclusion. Lung function, 6MWD, and quadriceps strength corrected for body weight (QS%) were recorded pre- and two-, six-, 13-, and 26-wk post-transplant. Fifty recipients, of mean (± SD) age 42 (± 13) yr, were studied. Mean FEV1 % and 6MWD improved from 26.4% to 88.9% and from 397 to 549 m at 26 wk, respectively (both p < 0.001). QS% declined in the first two wk but had improved to above pre-transplant levels by 26 wk (p = 0.027). On multivariate analysis (n = 35), lower pre-transplant exercise capacity and greater recovery in muscle strength explained most of the improvement in exercise capacity. Delayed recovery of exercise capacity after lung transplantation is unrelated to delay in improvement in graft function, but occurs secondary to the slow recovery of muscle strength. Our findings show that additional controlled trials are needed to better understand the influence of exercise rehabilitation on improvement in exercise capacity post-transplantation.

Metabolic disease and participant age are independent predictors of response to pulmonary rehabilitation.

PURPOSE: The study aims were (1) to determine whether baseline measures-including the Body Mass Index, Airflow Obstruction, Dyspnea, and Exercise Capacity (BODE) index; Age, Dyspnea, and Airflow Obstruction (ADO) index; physical activity; comorbidities (cardiac, metabolic, or musculoskeletal disease); and the number of hospitalizations over the previous 12 months-can predict responders in 6-minute walk distance (6MWD) following pulmonary rehabilitation (PR) and (2) to determine whether different methods in defining improvement in 6MWD affected identifying responders to PR. METHODS: All participants with chronic obstructive pulmonary disease who attended PR at our institution between 2004 and 2009 were evaluated. A participant was classified as a responder with improvement in 6MWD (≥25 m or ≥2 SD of this dataset coefficient of repeatability). RESULTS: A total of 203 participants (mean age, 68.2 ± 8.7 years; mean predicted forced expiratory volume in 1 second, 52.5 ± 22.4%) were analyzed. One hundred twenty participants (59.1%) had a comorbidity categorized as cardiac, metabolic, or musculoskeletal disease. The binary logistic regression models showed that younger participants (P ≤ .015) and, when using the coefficient of repeatability method (≥60.9 m), participants with metabolic disease (P = .040) were the only independent predictors of response. No other measure, including participant BODE or ADO index scores, contributed to either model. CONCLUSION: Identifying responders in exercise capacity following PR remains difficult, with only age and participants with metabolic disease identified as independent predictors.

Balance is impaired in people with chronic obstructive pulmonary disease.

BACKGROUND: It has recently been suggested that people with chronic obstructive pulmonary disease have an increased risk of falls. Although falls risk is multifactorial, impaired balance may contribute. The primary aim of this study was to compare balance between people with and without chronic obstructive pulmonary disease and the secondary aim was to determine if balance deteriorates when respiratory demand is increased by upper limb exercise. METHODS: Twelve people with chronic obstructive pulmonary disease and 12 healthy control subjects participated in this study. Participants stood on a force plate to record centre of pressure displacement during a range of conditions that challenge balance. Lumbar spine and hip motion were measured with inclinometers. Balance trials were performed before and after participation in upper limb exercise that increased respiratory demand in those with chronic obstructive pulmonary disease. FINDINGS: People with chronic obstructive pulmonary disease had increased mediolateral centre of pressure displacement and increased angular motion of the hip compared to healthy controls. Mediolateral centre of pressure displacement was further increased in people with chronic obstructive pulmonary disease following exercise, but unchanged in controls. Anteroposterior centre of pressure displacement did not differ between groups. INTERPRETATION: People with chronic obstructive pulmonary disease have reduced control of balance in the mediolateral direction. This may contribute to an increased risk of falls in this population.

Predictive utility of the 6-minute walk distance on survival in patients awaiting lung transplantation.

BACKGROUND: The 6-minute walk distance (6MWD) is a widely used clinical indicator of exercise capacity. Although used as part of the assessment process in determining a candidate's suitability for lung transplantation (LT), the literature describing the impact of the 6MWD in predicting survival on LT waiting lists is limited. This study aimed to determine the hazard function associated with the 6MWD, and its utility relative to other prognostic variables. METHODS: A retrospective chart review was conducted on 163 patients who were listed for single or double LT, and either survived to transplant or died while on the waiting list. A Cox regression for survival analysis, stratified by diagnostic group, was conducted utilizing the 6MWD, demographic variables and measures of cardiopulmonary function. RESULTS: The 6MWD proved to be the only significant covariate in the Cox regression for survival analysis (p < 0.001), with all other variables eliminated as non-significant. Furthermore, there was a protective effect for each unit increase in the 6MWD [Exp (B) = 0.994, 95% confidence interval 0.990 to 0.997]. CONCLUSIONS: This research demonstrates that the 6MWD is useful for stratifying patients on the LT waiting list by identifying those patients with a significantly higher risk of mortality.