Duchenne Muscular Dystrophy: Continuous Noninvasive Ventilatory Support Prolongs Survival

Abstract

OBJECTIVE: To describe survival outcomes with noninvasive ventilation (NIV) for full ventilatory support, and a mechanically assisted cough and oximetry protocol in a series of patients with Duchenne muscular dystrophy. METHODS: We monitored end-tidal carbon dioxide (P ETCO 2 ), S pO 2 , vital capacity, maximum insufflation capacity, and cough peak flow. Nocturnal NIV was initiated for symptomatic hypoventilation. An oximeter and mechanically assisted cough device were prescribed when the patient's maximum assisted cough peak flow fell below 300 L/min. Patients used up to continuous NIV and mechanically assisted cough to return S pO 2 to > 95% during intercurrent respiratory infections or as otherwise needed. We recorded respiratory and cardiac hospitalizations and mortality, and quantified survival by duration of continuous NIV dependence (ie, unable to maintain oxygenation without the ventilator). RESULTS: With advancing Duchenne muscular dystrophy, 101 nocturnal-only NIV users extended their NIV use throughout the daytime hours and required it continuously for 7.4 ؎ 6.1 years to 30.1 ؎ 6.1 years of age, with 56 patients still alive. Twenty-six of the 101 became continuously dependent without requiring hospitalization. Eight tracheostomized users were decannulated to NIV. Thirty-one consecutive unweanable intubated patients were extubated to NIV plus mechanically assisted cough. Of the 67 deaths (including 8 patients who died from heart failure before requiring ventilator use), 34 (52%) were probably cardiac, 14 (21%) were probably respiratory, and 19 (27%) were of unknown or other etiology. CONCLUSIONS: Continuous NIV along with mechanically assisted cough and oximetry as needed can prolong life and obviate tracheotomy in patients with Duchenne muscular dystrophy. Unweanable patients can be decannulated and extubated to NIV plus mechanically assisted cough.

Noninvasive ventilation as a palliative measure

“…More recent investigations of NIV have been observational in nature or controlled trials in which specific outcomes are evaluated in patients affected by a single disease, namely amyotrophic lateral sclerosis (ALS) [22,23,24 && ,25] and Duchenne muscular dystrophy (DMD) [26,27 && ,28]. Several well conducted studies [22,26,29,30] show that NIV improves survival in chest wall and NMDs. Some authors believe that future work in this field should try to explain global disparities in access to NIV [31 && ].…”

Psychosocial Support Needs of Families of Boys with Duchenne Muscular Dystrophy

“…Corticosteroid therapy offers benefit to DMD boys by improving muscle strength and function [Mendell et al, 1989;Griggs et al, 1991], prolonging independent ambulation [Biggar et al, 2001;Schara et al, 2001], plus slowing the progression of cardiomyopathy [Markham et al, 2008] and scoliosis [Kinali et al, 2007]. As well, the introduction of noninvasive positive pressure ventilation has prolonged the survival of individuals with DMD [Bach & Martinez, 2011].…”

Not to Invade: A Better Strategy?

“…They report survival as long as 25 years on full-time NIV, 3 which is certainly a greater lifespan for individuals with Duchenne muscular dystrophy than one would expect without ventilatory support. 4 However, we do not know whether patients on full-time NIV live longer than those with tracheostomy, as Bach and Martinez had no control group.…”

“…4 However, we do not know whether patients on full-time NIV live longer than those with tracheostomy, as Bach and Martinez had no control group. 3 It seems unlikely that a randomized controlled trial of fulltime NIV versus tracheostomy ventilation will be performed, because there may not be sufficient equipoise, at least at centers where full-time NIV is available. The sustained benefit of NIV in Duchenne muscular dystrophy partly depends on the maintenance of bulbar function.…”