Physiotherapist perspectives of airway clearance techniques in bronchiectasis.

INTRODUCTION: Our understanding regarding the personalization of airway clearance techniques (ACTs) in bronchiectasis is limited. OBJECTIVE: This study aimed to determine physiotherapist perceptions regarding the prescription of ACTs in inpatients and outpatients with bronchiectasis. METHODS: A single-center qualitative study using semi-structured interviews of physiotherapists who treated individuals with bronchiectasis was undertaken. All interviews were audio recorded and transcribed verbatim. Data was analyzed using the thematic framework approach described by Braun and Clark. NVivo 12 software assisted with coding and thematic analysis of the interview transcripts. Findings were summarized into major conceptual themes. Participant demographic data was also obtained. RESULTS: Eleven physiotherapists participated in the interviews. Central to all themes was the complexity of physiotherapy clinical decision-making regarding ACT prescription. Main themes included: organizational factors (i.e. workload, scope of service, access to resources/ACTs); patient-related factors (i.e. symptom severity, finances, disease-specific knowledge, social commitments, clinical setting, and perceived benefit); and physiotherapist/profession-related factors (i.e. clinical experience, access to professional support and education, awareness of evidence of ACTs, and evaluating ACT effectiveness). CONCLUSION: Physiotherapists regularly and routinely prescribe ACTs for individuals with bronchiectasis allowing for a multitude of competing factors. These factors should be considered by physiotherapists to enhance the personalized prescription of ACTs and may help promote patient adherence to ACTs to improve outcomes.

Exertional dyspnea responses to the Dyspnea Challenge in heart failure: Comparison to chronic obstructive pulmonary disease.

BACKGROUND: In heart failure (HF), exertional dyspnea is a common symptom, but validated field-based tests for its measurement are limited. The Dyspnea Challenge is a two-minute uphill treadmill walk designed to measure exertional dyspnea in cardiopulmonary disease. OBJECTIVES: The purpose of this study was to establish the test-retest reliability of the Dyspnea Challenge in HF and to compare the exercise responses to a group with chronic obstructive pulmonary disease (COPD). METHODS: The study was an experimental, single-blind, randomized, multi-site project that recruited individuals with HF (New York Heart Association I-III) and COPD (Global Initiative for Chronic Obstructive Lung Disease II-IV). Participants completed two visits. On the first visit, participants performed two six-minute walk tests (6MWT), followed by two to three Dyspnea Challenges to calculate treadmill speed and gradient. At Visit Two, participants performed two separate Dyspnea Challenges, with one including measures of pulmonary gas exchange and central hemodynamics. RESULTS: Twenty-one individuals with HF (10 female; 66±11years; ejection fraction:45.3 ± 6.1%; six-minute distance(6MWD) 520 ± 97 m), and 25 COPD (11 female; 68 ± 10 yr; forced expiratory volume in 1 s:47.6 ± 11.5%; 6MWD: 430 ± 101 m). Intraclass correlation coefficients demonstrated excellent test-retest reliability for HF (0.94, P<.01) and COPD (0.95, P<.01). While achieving similar end-exercise exertional dyspnea intensities (P=.60), the HF group walked at a higher average speed (4.2 ± 0.8 vs. 3.5 ± 0.8km·h-1) and gradient (10.3 ± 2.8 vs. 9.6 ± 2.8%) and a greater oxygen uptake (P<.01) and ventilation (P<.01) than those with COPD. While achieving similar cardiac outputs (P=.98), stroke volumes (P=.97), and heart rates (P=.83), those with HF displayed a larger arteriovenous oxygen difference (P<.01), while those with COPD exhibited greater decreases in inspiratory capacity (P=.03), arterial oxygen saturation (P=.02), and breathing reserve (P<.01). CONCLUSIONS: The Dyspnea Challenge is a reliable test-retest measure of exertional dyspnea in HF. Typical to their pathologies, HF seemed limited by an inadequate modulation of cardiac output, while ventilatory constraints hampered those with COPD.

Patient perspectives of airway clearance techniques in bronchiectasis.

INTRODUCTION: While airway clearance techniques (ACTs) are recommended for individuals with bronchiectasis, data suggests the use of and adherence to ACTs is poor. OBJECTIVE: This study aimed to identify patient perceptions regarding ACTs, the barriers and facilitators to ACTs, and factors affecting adherence. METHODS: A multi-center qualitative study using in-depth semi-structured interviews of individuals with bronchiectasis was undertaken. All interviews were audio recorded and transcribed verbatim. Data was analyzed using the thematic framework approach described by Braun and Clark. NVIVO™ 12 software assisted with coding and thematic analysis of the interview transcripts. Data saturation was achieved when no new common themes were identified. Findings were summarized into major conceptual themes. Participant demographic data was also obtained. RESULTS: Twenty-four participants participated in semi-structured interviews. The main facilitators to using ACTs included a perceived health and quality of life benefit, a tailored approach to ACTs and the use of self-management strategies. Main barriers included lack of time and motivation, lack of access to resources, and a lack of perceived health benefit. A number of factors were identified by participants that may help promote adherence including combining and trialing different ACTs, receiving regular ACT reviews and education from physiotherapists, and having good social support. CONCLUSION: To assist the personalized prescription of ACTs, these facilitators and barriers should be considered by clinicians to help promote adherence and improve patient outcomes.

Exertional Dyspnoea responses reported in the Dyspnoea Challenge and measures of disease severity in COPD.

BACKGROUND: The Dyspnoea Challenge has been developed to facilitate the field-based measure of exertional dyspnoea(ED). To further validate the test, we aimed to; investigate the relationship between end-exercise ED, generated by a fixed-intensity Dyspnoea Challenge(DCFIX), and measures of disease severity (Forced expiratory volume in 1 s(FEV1), six-minute walk distance(6MWD), breathing reserve(V̇E/MVV), modified medical research council dyspnoea scale (mMRC), Body-mass index, airflow Obstruction, Dyspnoea, and Exercise (BODE index) and compare the physiological response of the DCFIX to a six-minute walk test(6MWT). METHODS: Thirty-two individuals (15 female) with COPD (GOLD II-IV) (age: 69.7 ± 9.4 yrs; FEV1: 49.1 ± 18.2 %) performed 2×6MWT and 2xDCFIX at a treadmill speed of 3 km h-1 and gradient of 4 %. The intensity of ED was measured using the modified Borg dyspnoea scale at baseline and end-exercise with heart rate (HR) and oxygen saturation (SpO2) monitored continuously. During 1×6MWT and 1xDCFIX pulmonary gas exchange, cardiac output (Q̇) and dynamic hyperinflation were measured. RESULTS: End-exercise ED measured during the DCFIX was not correlated to FEV1, but moderately correlated to; 6MWD(rs = -0.54, P < .01), V̇E/MVV (rs = 0.46, P = .02), mMRC(rs = 0.45, P = .01), and the BODE index(rs = 0.53, P < .01). When comparing the DCFIX and 6MWT, participants walked to comparable levels of oxygen consumption(P = .38), ventilation(P = .37), Q̇(P = .20), V̇E/MVV(P = .83), maximum HR percentages(P = .67) and dynamically hyperinflated to a similar degree(P = .37). CONCLUSIONS: The Dyspnoea Challenge is correlated to different parameters of disease severity and produces a similar physiological and ED response to that of the 6MWT with the added benefit of being appropriate for longitudinal assessment of ED.

Optimising the Dyspnoea Challenge: exertional dyspnoea responses to changing treadmill gradients.

BACKGROUND: The Dyspnoea Challenge is a two-minute treadmill walk designed to measure exertional dyspnoea(ED). To efficiently individualise workload, we aimed to assess; 1) whether the Dyspnoea Challenge is responsive to 1% changes in treadmill gradient and 2) the minimum gradient variation necessary to generate a clinically meaningful change in ED (≥1 modified Borg scale). METHODS: Thirty individuals with COPD(GOLD II-IV) (age: 69.2 ± 9.2 years; FEV1: 49.3 ± 19.1%) completed six Dyspnoea Challenges at a fixed treadmill speed of 3 km·h-1 and at a gradient of between 3% and 8%, performed in random order. ED intensity and leg fatigue were measured using the 0-10 modified Borg scale. Heart rate(HR) and oxygen saturation(SpO2) were monitored continuously. A multidimensional dyspnoea profile(MDP) was used to quantify the discomfort, physical, e.g., work/effort and breathing frequency, and emotional components of ED. RESULTS: Higher treadmill gradients generated stronger intensities of ED (3%:2.6 ± 1.8; 4%:2.8 ± 2.2; 5%:3.2 ± 2.2; 6%:3.4 ± 2.2; 7%:3.7 ± 1.8; 8%:4.0 ± 2.1units). Statistical changes were observed in ED(e.g.,3 vs. 5%: P = .03) and the MDP discomfort data(e.g.,4 vs. 6%: P = .04) at ≥ a 2% variation in treadmill gradient. Linear regression found a 4% variation in treadmill gradient corresponded to a rise in ED ≥ 1unit. Increases in ED intensity corresponded to heightened sensations of work/effort(P < .01) and breathing frequency(P < .01). There were no changes in emotional constructs(P = .27). While there was an increase in HR with increasing gradient(P < .01), no differences were observed in end-exercise SpO2(P = .79) or leg fatigue(P = .06). CONCLUSION: To significantly change ED, the treadmill gradient must be manipulated by ≥ 2%, with a ≥ 4% change in gradient required to induce a clinically meaningful change in ED.

Measuring airway clearance outcomes in bronchiectasis: a review.

While airway clearance techniques (ACTs) are recommended for individuals with bronchiectasis, many trials have demonstrated inconsistent benefits or failed to reach their primary outcome. This review determined the most common clinical and patient-reported outcome measures used to evaluate the efficacy of ACTs in bronchiectasis. A literature search of five databases using relevant keywords and filtering for studies published in English, up until the end of August 2019, was completed. Studies included randomised controlled trials, using crossover or any other trial design, and abstracts. Studies were included where the control was placebo, no intervention, standard care, usual care or an active comparator. Adults with bronchiectasis not related to cystic fibrosis were included. Extracted data comprised study authors, design, duration, intervention, outcome measures and results. The search identified 27 published studies and one abstract. The most common clinical outcome measures were sputum volume (n=23), lung function (n=17) and pulse oximetry (n=9). The most common patient-reported outcomes were health-related quality of life (measured with St George's Respiratory Questionnaire, n=4), cough-related quality of life (measured with Leicester Cough Questionnaire, n=4) and dyspnoea (measured with Borg/modified Borg scale, n=8). Sputum volume, lung function, dyspnoea and health- and cough-related quality of life appear to be the most common clinical and patient-reported measures of airway clearance treatment efficacy.

Longevity of pulmonary rehabilitation benefit for chronic obstructive pulmonary disease-health care utilisation in the subsequent 2 years.

Background: The primary aim was to determine the healthcare utilisation benefits including respiratory-related hospital admissions, hospital admission days and emergency department presentations in the 0-12 and 12-24 months postpulmonary rehabilitation compared with the 12 months preprogramme. Methods: An observational, data-linkage design of 11 standardised pulmonary rehabilitation programmes were used. All programmes were 8 weeks in duration with two supervised exercise sessions per week and were required to use the national pulmonary rehabilitation recommendations with regard to programme organisation, exercise training guidelines and multidisciplinary education. For each participant with chronic obstructive pulmonary disease (COPD), healthcare utilisation data were collected for the 12 months preprogramme and 24 months postprogramme. Results: 426 participants (231 males, FEV149.3 (19.6) % predicted) were studied. The number of respiratory admissions/participant/year decreased from 0.7 (1.1) in the 12 months preprogramme to 0.5 (1.9) in the 12 months postprogramme, p=0.083; but increased in the 12-24 months postprogramme to 1.0 (2.3), p<0.001. The hospital days/participant/year improved from 4.0 (7.8) days in the 12 months preprogramme to 2.5 (8.5) days in the 12 months postprogramme, p<0.001; but increased in the 12-24 months postprogramme to 6.1 (16.6) days, p=0.004. The emergency department presentations/participant/year improved from 1.15 (1.75) in the 12 months preprogramme to 0.9 (1.8) in the 12 months postprogramme, p=0.003; but increased in the 12-24 months postprogramme to 2.0 (3.3), p<0.001. Conclusion: Pulmonary rehabilitation significantly improves hospital days and emergency department presentations in the first 12 months postprogramme. Healthcare utilisation benefits in the second 12 months are less clear.

Cognitive behavioural therapy (CBT) for patients with chronic lung disease and psychological comorbidities undergoing pulmonary rehabilitation.

BACKGROUND: The study aimed to determine the effects of adding cognitive behavioural therapy (CBT) to pulmonary rehabilitation to treat patients with chronic lung disease and comorbid anxiety and/or depression symptoms. METHODS: An open, parallel group, randomised controlled trial (RCT) was conducted, with longitudinal follow-up of 12 months. CBT was delivered in 2 face-to-face sessions and 4 phone sessions to patients with depression or anxiety undergoing pulmonary rehabilitation. The main outcome measures were change in Geriatric Depression Scale (GDS) and Geriatric Anxiety Inventory (GAI); secondary outcomes were St. Georges Respiratory Questionnaire (SGRQ), 6-minute walk test (6MWT) and pulmonary rehabilitation attendance. RESULTS: A total of 65 patients were randomized to Intervention (n=24) and Control (n=41) groups. Of the 24 patients in the Intervention group, 6 patients (25%) withdrew and 4 patients (12.5%) failed to attend more than 2 CBT sessions, which was significantly more than the Control group. The majority of patients (75.4%) had chronic obstructive pulmonary disease. Fourteen (21.5%) had symptoms of depression only, 12 (18.4%) had symptoms of anxiety only, and 39 (60.0%) had symptoms of both anxiety and depression. In the Intervention group, GDS significantly improved at the end of pulmonary rehabilitation (mean difference -3.1, 95% CI: -4.39 to -1.70; P=0.0001), 3 months follow-up (mean difference -1.5, 95% CI: -4.17 to -0.75; P=0.008), and at 12 months follow-up (mean difference -1.6, 95% CI: -3.29 to -0.03, P=0.04), compared to baseline. The Control group demonstrated improvement in GDS by the end of pulmonary rehabilitation (mean difference -1.3, 95% CI: -2.4 to -0.27; P=0.01) which was not maintained at 3 months (P=0.14) and 12 months (P=0.25). GAI significantly improved by the end of rehabilitation in both the Intervention (mean difference -2.6, 95% -4.69 to -0.57; P=0.01) and Control groups (mean difference -2.6, 95% -4.16 to -1.14; P=0.001) and there was no significant improvement at 3 and 12 months. No statistically significant differences in changes in GDS or GAI were observed between the Intervention and Control groups at any time point. There was no significant improvement in SGRQ or 6MWT. There was a significant increase in attended pulmonary rehabilitation sessions in the Intervention group, compared to the Control group (mean difference 1.59; 95% CI: 0.11 to 3.07; P=0.03). CONCLUSIONS: In this RCT of patients with chronic lung diseases attending pulmonary rehabilitation, there was no evidence found for improved symptoms of anxiety or depression or health-related quality of life with the addition of CBT given in a mixed face-to-face and telephone format, compared to usual care. Slower than anticipated recruitment, leading to a smaller than planned sample size, and a high dropout rate in the group allocated to CBT may have limited the effectiveness of the behavioural intervention approach in this study.

Comparing the Performance Characteristics of Different Positive Expiratory Pressure Devices.

BACKGROUND: Positive expiratory pressure (PEP) devices are widely used in clinical settings, yet the performance characteristics of these devices remain relatively unknown. This study compared the performance characteristics of 6 airway clearance devices by varying resistance and flow. METHODS: Mean PEP, peak PEP, oscillation frequency, and amplitude PEP of the Flutter, Pari PEP S, Acapella Choice, Acapella DM, Acapella DH, and Aerobika devices were obtained across flows of 5, 10, 15, 20, 25 and 30 L/min and at low, medium, and high resistance using an experimental apparatus custom-built for this bench study. RESULTS: Performance characteristics of the devices differed across flows and resistance settings (device × flow/resistance interaction; P < .001). At a fixed resistance, increasing flows increased mean PEP produced by the Acapella Choice, Acapella DH, Aerobika, and Pari PEP S. Increasing flow resulted in minimal change in mean PEP produced by the Flutter and Acapella DM. Increasing flow increased peak PEP and amplitude PEP produced by all devices except the Acapella DH and Acapella Choice. Increasing flow maintained or increased oscillation frequency for all devices except the Flutter. At a fixed flow, increasing resistance increased mean PEP produced by all devices except the Acapella Choice. Increasing resistance increased peak PEP produced by the Acapella DM, Aerobika, and Pari PEP S but resulted in minimal change in peak PEP for the Flutter and Acapella Choice. Increasing resistance either maintained or increased oscillation frequency for all devices. Amplitude PEP was either maintained or increased during oscillations when increasing resistance for all devices except the Flutter. CONCLUSIONS: PEP devices produced small but statistically significant variations in performance characteristics across a range of flows and resistance settings. There appear to be flow-dependent and non-flow-dependent devices. Varying flow or resistance typically maintained or increased the production of mean, peak, and amplitude PEP and oscillation frequency.

Quadriceps Muscle Strength and Body Mass Index Are Associated With Estimates of Physical Activity Postheart Transplantation.

BACKGROUND: Although exercise capacity improves postheart transplantation (HTx), it remains unclear if the level of physical activity (PA) shows similar improvement. The purpose of this study was to (1) describe PA levels and (2) identify factors which may be associated with levels of PA post-HTx. METHODS: A prospective observational cross-sectional study was conducted at a single center HTx outpatient clinic. Medically stable adult recipients 6 months or longer post-HTx were recruited. Physical activity level (PAL) and average daily time spent at least moderately active (≥3 metabolic equivalents) were estimated using a multisensor device. Factors investigated were demographic (age, sex, body mass index [BMI], time post-HTx, and reason for HTx), corticosteroid use, exercise capacity (6-min walk distance), and quadriceps muscle strength corrected for body weight (QS%). RESULTS: The mean post-HTx time of the 75 participants was 9.2 ± 7.0 years (0.5-26 y). Twenty-seven (36%) participants were classified as extremely inactive (PAL, <1.40), 26 (34.6%) sedentary (1.40 ≤ PAL ≤ 1.69), and 22 (29.3%) active (PAL, ≥1.70). Multivariable analysis showed greater QS% (ß = 0.004 (0.002-0.006) P = 0.001) to be independently associated with increased PAL. For increased time, 3 or more metabolic equivalents both greater QS% (ß = 0.0164 [0.003-0.029]; P = 0.014) and lower BMI (ß = -0.0626 [-0.115 to -0.0099]; P = 0.021) were independently associated. CONCLUSIONS: The degree of observed sedentary behavior post-HTx is surprising, with the majority of participants not reaching levels of PA recommended for health benefits. QS% and BMI were the only factors found to be independently associated with estimates of PA. Further quality trials are required to demonstrate the long-term benefits of regular PA and investigate ways of increasing adherence to PA post-HTx.

Long-Term Survival and Health-Related Quality of Life in Adults After Extra Corporeal Membrane Oxygenation.

BACKGROUND: The study aims to determine long-term survival, health-related quality of life (HRQoL) and functional and physical outcomes of adult extra corporeal membrane oxygenation (ECMO) patients as there are limited and conflicting data in this area. METHODS: All patients receiving ECMO from April 2009 until June 2014 at The Prince Charles Hospital, Brisbane had Kaplan Meier survival calculated. Quality of life (QoL) was assessed using the Short Form Health Survey (SF-36v2), EQ5D-5L, The Frenchay Activities Index (FAI) and a return to work survey. From December 2011, these measures and 6-minute walk distance (6MWD) were assessed at hospital discharge and 12 months post-discharge. RESULTS: Seventy-seven (77) patients (45 veno-arterial and 32 veno-venous) received ECMO of whom 47/77 (61%) survived to hospital discharge. There were no deaths recorded in those discharged alive from the intensive care unit at median follow-up time 1,011days (range 227-2,014 days). Mean SF-36 scores (n=33) and EQ5D were assessed at a median of 606days after hospital discharge. SF-36 scores were significantly (p<0.05) worse than age-matched norms in all domains except vitality, bodily pain and mental health. Thirteen (13) (39%) participants had persistent problems with mobility and usual activity as measured by EQ5D. At 12 months post-ECMO, 6MWD was 531(IQR:397.3-626.8)m; 72% (IQR:53.2-77.6%) predicted but had improved by 223m (p=0.002) when compared to baseline. Nineteen (19) of 20 participants who had been employed pre-ECMO had returned to work. CONCLUSIONS: All ECMO patients discharged from hospital were alive at follow-up. Despite improvements in physical measures and HRQoL, long-term functional deficits persist when compared to that of aged- and sex-matched norms.

A comparison of the effects of manual hyperinflation and ventilator hyperinflation on restoring end-expiratory lung volume after endotracheal suctioning: A pilot physiologic study.

PURPOSE: Endotracheal suctioning (ES) of mechanically ventilated patients decreases end-expiratory lung volume (EELV). Manual hyperinflation (MHI) and ventilator hyperinflation (VHI) may restore EELV post-ES but it remains unknown which method is most effective. The primary aim was to compare the efficacy of MHI and VHI in restoring EELV post-ES. MATERIALS AND METHODS: ES was performed on mechanically ventilated intensive care patients, followed by MHI or VHI, in a randomised crossover design. The washout period between interventions was 1 h. End-expiratory lung impedance (EELI), measured by electrical impedance tomography, was recorded at baseline, during ES, during hyperinflation and 1, 5, 15 and 30 min post-hyperinflation. RESULTS: Nine participants were studied. ES decreased EELI by 1672z (95% CI, 1204 to 2140) from baseline. From baseline, MHI increased EELI by 1154z (95% CI, 977 to 1330) while VHI increased EELI by 769z (95% CI, 457 to 1080). Five minutes post-VHI, EELI remained 528z (95% CI, 4 to 1053) above baseline. Fifteen minutes post-MHI, EELI remained 351z (95% CI, 111 to 592) above baseline. At subsequent time-points, EELI returned to baseline. CONCLUSIONS: MHI and VHI effectively restore EELV above baseline post-ES and should be considered post suctioning.

Differences in the daily activity of patients with diabetic foot ulcers compared to controls in their free-living environments.

The aims of our study were to investigate multiple daily activity outcomes in patients with diabetic foot ulcers (DFU) compared to diabetic peripheral neuropathy (DPN) and diabetes (DM) controls in their free-living environments. We examined daily activity outcomes of 30 patients with DFU, 23 DPN and 20 DM. All patients wore a validated multi-sensor device for > 5 days (>22 hours per day) to measure their daily activity outcomes: steps, energy expenditure (kJ), average metabolic equivalent tasks (METs), physical activity (>3·0 METs) duration and energy expenditure, lying duration, sleep duration and sleep quality. We found that DFU patients recorded fewer median (interquartile ranges, IQR) daily steps [2154 (1621-4324)] than DPN [3660 (2742-7705)] and DM [5102 (4011-7408)] controls (P < 0·05). In contrast, DFU patients recorded more mean ± SD daily energy expenditure (kJ) (13 006 ± 3559) than DPN (11 085 ± 1876) and DM (11 491 ± 1559) controls (P < 0·05). We found no other differences in daily activity outcomes (P > 0·1). We conclude that DFU patients typically take fewer steps but expend more energy during their normal daily activity than DPN and DM controls. We hypothesise that the increased energy expenditure for DFU patients may be due to wound healing or an inefficient gait strategy. Further investigations into this energy imbalance in DFU patients may improve healing in future.

Anxiety and depression-Important psychological comorbidities of COPD.

Anxiety and depression are common and important comorbidities in patients with chronic obstructive pulmonary disease (COPD). The pathophysiology of these psychological comorbidities in COPD is complex and possibly explained by common risk factors, response to symptomatology and biochemical alterations. The presence of anxiety and/or depression in COPD patients is associated with increased mortality, exacerbation rates, length of hospital stay, and decreased quality of life and functional status. There is currently no consensus on the most appropriate approach to screening for anxiety and depression in COPD. Treatment options include psychological [relaxation, cognitive behavioural therapy (CBT), self-management] and pharmacological interventions. Although there is some evidence to support these treatments in COPD, the data are limited and mainly comprised by small studies. Pulmonary rehabilitation improves anxiety and depression, and conversely these conditions impact rehabilitation completion rates. Additional high quality studies are urgently required to optimise screening and effective treatment of anxiety and depression in patients with COPD, to enhance complex chronic disease management for these patients.

A simple clinical measure of quadriceps muscle strength identifies responders to pulmonary rehabilitation.

The aim was to determine if baseline measures can predict response to pulmonary rehabilitation in terms of six-minute walk distance (6MWD) or quality of life. Participants with COPD who attended pulmonary rehabilitation between 2010 and 2012 were recruited. Baseline measures evaluated included physical activity, quadriceps strength, comorbidities, inflammatory markers, and self-efficacy. Participants were classified as a responder with improvement in 6MWD (criteria of ≥25 m or ≥2SD) and Chronic Respiratory Questionnaire (CRQ; ≥0.5 points/question). Eighty-five participants with a mean (SD) age of 67(9) years and a mean forced expiratory volume in one second of 55(22)% were studied. Forty-nine and 19 participants were responders when using the 6MWD criteria of ≥25 m and ≥61.9 m, respectively, with forty-four participants improving in CRQ. In a regression model, responders in 6MWD (≥25 m criteria) had lower baseline quadriceps strength (P = 0.028) and higher baseline self-efficacy scores (P = 0.045). Independent predictors of 6MWD response (≥61.9 m criteria) were participants with metabolic disease (P = 0.007) and lower baseline quadriceps strength (P = 0.016). Lower baseline CRQ was the only independent predictor of CRQ response. A participant with relatively lower baseline quadriceps strength was the strongest independent predictor of 6MWD response. Metabolic disease may predict 6MWD response, but predictors of CRQ response remain unclear.

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.