Randomized trial of lung hyperinflation therapy in children with congenital muscular dystrophy

Abstract

Objective Respiratory compromise in congenital muscular dystrophy (CMD) occurs, in part, from chest wall contractures. Passive stretch with hyperinsufflation therapy could reduce related costo‐vertebral joint contractures. We sought to examine the impact of hyperinsufflation use on lung function and quality of life in children with CMD. Study Design We conducted a randomized controlled trial on hyperinsufflation therapy in children with CMD at two centers. An individualized hyperinsufflation regimen of 15 minutes twice daily using a cough assist device over a 12 months period was prescribed. We measured lung function, quality of life, and adherence. To demonstrate reproducibility, pulmonary function was measured twice on the same day. A mixed‐effects regression model adjusting for confounders was used to assess the effects of hyperinsufflation. Results We enrolled 34 participants in the study; 31 completed the trial (n = 17 treatment group and n = 14 controls). Participants in the treatment group demonstrated a relative gain in lung volume measured at 4 and 8 months, but not at 12 months. The control group required increases in the maximum insufflation pressures to achieve maximum lung volumes while the treatment group did not. Adherence was best early in the study, peaking at the first visit and decreasing at subsequent visits. Caregiver‐reported quality of life was higher in the treatment group. Conclusion Hyperinsufflation therapy is effective in increasing and sustaining lung volume over time. Adherence, however, was inconsistent and difficult to maintain. Further research should determine if improved adherence leads to sustained benefits of hyperinsufflation.

Understanding the experiences of lung volume recruitment among boys with Duchenne muscular dystrophy: A multicenter qualitative study

“…Our team's recent randomized trial of LVR using a self‐inflating resuscitation bag with a one‐way valve reported an adherence rate of 41% over 2 years 11 . Similar adherence rates (31%–60%) have been reported in studies evaluating alternative preventive respiratory therapies aimed at maintaining cough strength, such as mechanical insufflation‐exsufflation 12–14 . There is a need to better understand factors that promote or impede the use of LVR, to facilitate its implementation into clinical care and ensure optimal outcomes.…”

“…Our study identified that perceived benefits had a strong influence on perceptions of the utility of LVR and motivation to use it. While lack of symptom improvement has not been previously identified as a barrier to cough augmentation technique use, 12,25,27,28 greater disease severity, more symptoms at baseline, and symptom improvement following treatment, have been associated with greater adherence in both children and adults with neuromuscular disease. 26,29,30 Similarly, children in our study who met the threshold of adherence had a lower FVC at baseline and were more likely to be wheelchair-assisted, which may imply greater respiratory dysfunction.…”

“…11 Similar adherence rates (31%-60%) have been reported in studies evaluating alternative preventive respiratory therapies aimed at maintaining cough strength, such as mechanical insufflationexsufflation. [12][13][14] There is a need to better understand factors that promote or impede the use of LVR, to facilitate its implementation into clinical care and ensure optimal outcomes. To date, no studies have evaluated acceptability of LVR using a self-inflating resuscitation bag in children with neuromuscular disease.…”

A Randomized Controlled Clinical Trial of Lung Volume Recruitment in Adults with Neuromuscular Disease

“…Median FVC at baseline was 85%pn, and only 6% of participants were NIV users, indicating that LVR was initiated when respiratory compromise was mild. In a study of 34 children with muscular dystrophy and worse respiratory function (median FVC, 56%pn), volume recruitment using a mechanical insufflation–exsufflation device improved FVC more than a no-treatment control at interim visits but not at 12 months ( 31 ). Taken together, the pediatric and adult RCT data suggest that prophylactic LVR does not modify respiratory mechanics within 2 years.…”

The Use of Autologous Blood Patch in Ullrich Muscular Dystrophy and Recurrent Pneumothorax

“…To the best of our knowledge, no lung pathology in these collagen-VI-related disorders has been published. Patients with neuromuscular dystrophy and respiratory failure are often treated with non-invasive ventilation in addition to adjunctive therapies like lung volume recruitment and mechanical insufflationexsufflation [5]. Some studies have found that these therapies "increase inspiratory capacity above maximal spontaneous inspiration" and, thus, increase the risk of pneumothoraces [6].…”