Telerehabilitation Using Fitness Application in Patients with Severe Cystic Fibrosis Awaiting Lung Transplant: A Pilot Study.

PURPOSE: The purpose of this study was to pilot a home-based pulmonary rehabilitation (PR) program administered via a telemedicine approach using a combination of fitness application and self-selected activity in lung transplant candidates with cystic fibrosis (CF). METHODS: We recruited adult patients with CF. The main outcome was adherence, measured by number of sessions completed in 12 weeks. Secondary outcomes were adverse events, six-minute walk distance (6MWD), and dyspnea. Participants were provided a personalized exercise program and equipment including a fitness application that provided exercise videos, recorded exercise time, and corresponding heart rate. We reviewed data daily and provided text messages with feedback. We compared our study outcomes to a retrospective data set of CF patients who participated in a 24-session outpatient hospital-based PR program. Data presented as mean ± standard deviation. RESULTS: Eleven patients participated in the home PR program, 45% female, age 33 ± 7 years, FEV1 27 ± 5% predicted. Sessions completed were 19 ± 12 home-based PR vs. 9 ± 4 hospital-based PR, p = .03. Fifty percent of the home-based group completed ≥24 sessions in 12 weeks versus 0% of the hospital-based patients (p = .03). There were no adverse events during exercise. Completers of the home-based program demonstrated a clinically meaningful lower decline in 6 MWD than noncompleters (6MWD -7 ± 15 vs. -86 ± 108 meters). Only one participant performed a post 6 MWD in the hospital-based PR. CONCLUSION: Patients with severe CF demonstrated adherence to home PR delivered using fitness application and self-selected activity with no adverse events. This program style may be a viable solution for telerehabilitation in severe CF and is particularly relevant in the COVID era.

Increasing Opportunity for Lung Transplant in Interstitial Lung Disease With Pulmonary Hypertension.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation for end-stage interstitial lung disease (ILD) and pulmonary hypertension (PH) has varying results based on ECMO configuration. We compare our experience using venovenous (VV) and venoarterial (VA) ECMO bridge to transplantation for ILD with PH on survival to successful transplantation. METHODS: A single-center retrospective review was done of patients with ILD and secondary PH who were placed on either VV or VA ECMO as bridge to transplantation from 2010 to 2016. Comparisons for factors associated with survival to transplantation between VV and VA ECMO strategies were made using Cox proportional hazards model. Subgroup analysis included comparisons of VV ECMO patients who remained on VV or were converted to VA ECMO. RESULTS: A total of 50 patients with ILD and PH were treated initially with either VV (n = 19) or VA (n = 31) ECMO as bridge to lung transplantation. Initial VA ECMO had a significantly higher survival to transplantation compared with initial VV ECMO (p = 0.03). Cox proportional hazards modeling showed a 59% reduction in risk of death for VA compared with VV ECMO (hazard reduction 0.41, 95% confidence interval: 0.18 to 0.92, p = 0.03). Patients converted from VV to VA ECMO had significantly longer survival awaiting transplant than patients who remained on VV ECMO (p = 0.03). Ambulation on ECMO before transplantation was associated with an 80% reduction in the risk of death (hazard reduction 0.20, 95% confidence interval: 0.08 to 0.48, p < 0.01). CONCLUSIONS: Venoarterial ECMO upper body configuration for patients with end stage ILD and PH significantly improves overall survival to transplantation.

Frailty and maximal exercise capacity in adult lung transplant candidates.

BACKGROUND: Frail lung transplant candidates are more likely to be delisted or die without receiving a transplant. Further knowledge of what frailty represents in this population will assist in developing interventions to prevent frailty from developing. We set out to determine whether frail lung transplant candidates have reduced exercise capacity independent of disease severity and diagnosis. METHODS: Sixty-eight adult lung transplant candidates underwent cardiopulmonary exercise testing (CPET) and a frailty assessment (Fried's Frailty Phenotype (FFP)). Primary outcomes were peak workload and peak aerobic capacity (V˙O2). We used linear regression to adjust for age, gender, diagnosis, and lung allocation score (LAS). RESULTS: The mean ± SD age was 57 ± 11 years, 51% were women, 57% had interstitial lung disease, 32% had chronic obstructive pulmonary disease, 11% had cystic fibrosis, and the mean LAS was 40.2 (range 19.2-94.5). In adjusted models, peak workload decreased by 10 W (95% CI 4.7 to 14.6) and peak V˙O2 decreased by 1.8 mL/kg/min (95% CI 0.6 to 2.9) per 1 unit increment in FFP score. After adjustment, exercise tolerance was 38 W lower (95% CI 18.4 to 58.1) and peak V˙O2 was 8.5 mL/kg/min lower (95% CI 3.3 to 13.7) among frail participants compared to non-frail participants. Frailty accounted for 16% of the variance (R2) of watts and 19% of the variance of V˙O2 in adjusted models. CONCLUSION: Frailty contributes to reduced exercise capacity among lung transplant candidates independent of disease severity.

Quantification of Improvements in Static and Dynamic Ventilatory Measures Following Lung Volume Reduction Surgery for Severe COPD.

Rationale: This study quantitatively measured the effects of lung volume reduction surgery (LVRS) on spirometry, static and dynamic lung and chest wall volume subdivision mechanics, and cardiopulmonary exercise measures. Methods: Patients with severe COPD (mean FEV1 = 23 ± 6% predicted) undergoing LVRS evaluation were recruited. Spirometry, plethysmography and exercise capacity were obtained within 6 months pre-LVRS and again within 12 months post- LVRS. Ventilatory mechanics were quantified using stationary optoelectronic plethysmography (OEP) during spontaneous tidal breathing and during maximum voluntary ventilation (MVV). Statistical significance was set at P< 0.05. Results:Ten consecutive patients met criteria for LVRS (5 females, 5 males, age: 62±6yrs). Post -LVRS (mean follow up 7 months ± 2 months), the group showed significant improvements in dyspnea scores (pre 4±1 versus post 2 ± 2), peak exercise workload (pre 37± 21 watts versus post 50 ± 27watts ), heart rate (pre 109±19 beats per minutes [bpm] versus post 118±19 bpm), duty cycle (pre 30.8 ± 3.8% versus post 38.0 ± 5.7%), and spirometric measurements (forced expiratory volume in 1 second [FEV1] pre 23 ± 6% versus post 32 ± 13%, total lung capacity / residual lung volume pre 50 ± 8 versus 50 ± 11) . Six to 12 month changes in OEP measurements were observed in an increased percent contribution of the abdomen compartment during tidal breathing (41.2±6.2% versus 44.3±8.9%, P=0.03) and in percent contribution of the pulmonary ribcage compartment during MVV (34.5±10.3 versus 44.9±11.1%, P=0.02). Significant improvements in dynamic hyperinflation during MVV occurred, demonstrated by decreases rather than increases in end expiratory volume (EEV) in the pulmonary ribcage (pre 207.0 ± 288.2 ml versus post -85.0 ± 255.9 ml) and abdominal ribcage compartments (pre 229.1 ± 182.4 ml versus post -17.0 ± 136.2 ml) during the maneuver. Conclusions: Post-LVRS, patients with severe COPD demonstrate significant favorable changes in ventilatory mechanics, during tidal and maximal voluntary breathing. Future work is necessary to determine if these findings are clinically relevant, and extend to other environments such as exercise.

The effect of lung volume reduction surgery on chronotropic incompetence.

BACKGROUND: Chronotropic incompetence (CI) is a marker of poor prognosis in patients with COPD. Treatments that improve pulmonary function and exercise capacity may affect CI. Objectives are to evaluate CI before and after lung volume reduction surgery (LVRS) and determine if changes in CI are associated with changes in pulmonary function and exercise capacity. METHODS: We performed a retrospective review of 75 patients who underwent LVRS and who had complete cardiopulmonary exercise testing and concurrent pulmonary function tests two months before and about 6 months after surgery. Additionally we evaluated 28 control patients that were randomized to medical treatment as part of the National Emphysema Treatment Trial at our center. We studied CI using the percent of predicted heart rate reserve=(heart rate peak-heart rate rest)/((208-0.7×age)-heart rate rest)×100, before and after surgery and compared it to the control group. RESULTS: Mean percent of predicted heart rate reserve improved from 41% to 50% (p-value <0.001) after LVRS, while the control group did not change. The mean forced vital capacity and expiratory volume in 1s, peak oxygen consumption, carbon dioxide production, ventilation, tidal volume and maximal workload all improved in the surgery group, while the controls did not improve. CONCLUSIONS: CI improves after LVRS in a population of patients with COPD. CI improvements are associated with the increases in pulmonary function and exercise capacity. This improvement is seen in a domain of known cardiopulmonary impairment prior to surgery that improves as a positive response to the therapy of LVRS.