title: Lung volume recruitment slows pulmonary function decline in Duchenne muscular dystrophy.
abstract: OBJECTIVE
  To evaluate the long-term effect on measures of forced vital capacity (FVC) before and after the introduction of regular lung volume recruitment (LVR) maneuvers (breath-stacking) in individuals with Duchenne muscular dystrophy (DMD).
  
  
  METHODS
  Retrospective cohort study of pulmonary function data, including FVC, cough peak flow (CPF), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP). Data were collected for 33 months prior to and 45 months after LVR introduction.
  
  
  METHODS
  Ambulatory care in a tertiary level regional rehabilitation center in Canada.
  
  
  METHODS
  All individuals (N=22) with DMD (mean age ± SD, 19.6±2.4y), who were prescribed LVR and reported adherence with therapy.
  
  
  METHODS
  Introduction of regular LVR (breath-stacking); 3 to 5 maximal lung inflations (maximum insufflation capacity [MIC]) using a hand-held resuscitation bag and mouthpiece, twice daily.
  
  
  METHODS
  Measures included the rate of decline of FVC in percent-predicted, before and after the introduction of regular LVR. Changes in maximum pressures (MIP, MEP), MIC, and cough peak flows were also measured.
  
  
  RESULTS
  At LVR initiation, FVC was 21.8±16.9 percent-predicted, and cough peak flows were <270L/min (144.8±106.9L/min). Annual decline of FVC was 4.7 percent-predicted a year before LVR and 0.5 percent-predicted a year after LVR initiation. The difference, 4.2 percent-predicted a year (95% confidence interval, 3.5-4.9; P<.000), represents an 89% improvement in the annual rate of FVC decline.
  
  
  CONCLUSIONS
  The rate of FVC decline in DMD patients improves dramatically with initiation of regular LVR.
authors.affiliation: Division of Respiratory Medicine, The Ottawa Hospital Rehabilitation Centre, Ottawa, ON, Canada. dmckim@Ottawahospital.on.ca
authors.forename: Douglas A
authors.initials: DA
authors.lastname: McKim
authors.forename: Sherri L
authors.initials: SL
authors.lastname: Katz
authors.forename: Nicholas
authors.initials: N
authors.lastname: Barrowman
authors.forename: Andy
authors.initials: A
authors.lastname: Ni
authors.forename: Carole
authors.initials: C
authors.lastname: LeBlanc
mesh_terms: D000293:Adolescent; D015331:Cohort Studies; D016001:Confidence Intervals; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008176:Lung Volume Measurements; D008297:Male; D020388:Muscular Dystrophy, Duchenne / Q000150:complications* / Q000503:physiopathology; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012129:Respiratory Function Tests; D012131:Respiratory Insufficiency / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D014109:Total Lung Capacity; D014797:Vital Capacity / Q000502:physiology*; D055815:Young Adult