title: Lung insufflation capacity in neuromuscular disease.
abstract: OBJECTIVE
  To compare maximal passive lung insufflation capacity (LIC) with lung inflation by air stacking (to maximum insufflation capacity [MIC]) and with vital capacity (VC); to explore relationships between these variables that correlate with glottic function and cough peak flows (CPF); to demonstrate the effect of routine inflation therapy on LIC and MIC; and to determine the relative importance of lung inflation therapy as a function of disease severity.
  
  
  METHODS
  Case series of 282 consecutive neuromuscular disease (NMD) clinic patients 7 yrs and older with VC <70% of the predicted normal value. All cooperative patients meeting these criteria were prescribed thrice-daily air stacking and/or maximal passive lung insufflation to pressures of 40-80 cm H2O, and they underwent measurements of VC, MIC, LIC, and unassisted and assisted CPF on every visit.
  
  
  RESULTS
  Means +/- standard deviations for VC, MIC, and LIC were 1131 +/- 744, 1712 +/- 926, and 2069 +/- 867 ml, respectively, and, for unassisted and assisted CPF, they were 2.5 +/- 2.0 and 4.3 +/- 2.2 liters/sec, respectively, with all differences statistically significant (P < 0.001). MIC minus VC correlated inversely with LIC minus MIC (P = 0.01) and, therefore, with glottic function. Both MIC and LIC increased with practice (P < 0.001). Increases in LIC but not MIC over VC were greatest for patients with the lowest VC (P < 0.05). There were no complications of lung mobilization therapy.
  
  
  CONCLUSIONS
  Passive lung insufflation can distend the lungs of patients with NMD significantly greater than air stacking, particularly when glottic and bulbar-innervated muscle dysfunction is severe. LIC, MIC, and VC measurements permit quantifiable assessment of glottic integrity and, therefore, bulbar-innervated muscle function for patients with NMD. The patients who benefit the most from insufflation therapy are those who have the lowest VC.
authors: Department of Physical Medicine and Rehabilitation, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark, New Jersey, USA.
authors: John Robert
authors: JR
authors: Bach
authors: Kedar
authors: K
authors: Mahajan
authors: Bethany
authors: B
authors: Lipa
authors: Lou
authors: L
authors: Saporito
authors: Miguel
authors: M
authors: Goncalves
authors: Eugene
authors: E
authors: Komaroff
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003371:Cough / Q000503:physiopathology; D006801:Humans; D007327:Insufflation; D008176:Lung Volume Measurements; D008875:Middle Aged; D009468:Neuromuscular Diseases / Q000503:physiopathology*; D013147:Spirometry