title: Effects of proportional assisted ventilation on exercise performance in idiopathic pulmonary fibrosis patients.
abstract: BACKGROUND
  Patients with idiopathic pulmonary fibrosis (IPF) present an important ventilatory limitation reducing their exercise capacity. Non-invasive ventilatory support has been shown to improve exercise capacity in patients with obstructive diseases; however, its effect on IPF patients remains unknown.
  
  
  OBJECTIVE
  The present study assessed the effect of ventilatory support using proportional assist ventilation (PAV) on exercise capacity in patients with IPF.
  
  
  METHODS
  Ten patients (61.2+/-9.2 year-old) were submitted to a cardiopulmonary exercise testing, plethysmography and three submaximal exercise tests (60% of maximum load): without ventilatory support, with continuous positive airway pressure (CPAP) and PAV. Submaximal tests were performed randomly and exercise capacity, cardiovascular and ventilatory response as well as breathlessness subjective perception were evaluated. Lactate plasmatic levels were obtained before and after submaximal exercise.
  
  
  RESULTS
  Our data show that patients presented a limited exercise capacity (9.7+/-3.8 mL O(2)/kg/min). Submaximal test was increased in patients with PAV compared with CPAP and without ventilatory support (respectively, 11.1+/-8.8 min, 5.6+/-4.7 and 4.5+/-3.8 min; p<0.05). An improved arterial oxygenation and lower subjective perception to effort was also observed in patients with IPF when exercise was performed with PAV (p<0.05). IPF patients performing submaximal exercise with PAV also presented a lower heart rate during exercise, although systolic and diastolic pressures were not different among submaximal tests. Our results suggest that PAV can increase exercise tolerance and decrease dyspnoea and cardiac effort in patients with idiopathic pulmonary fibrosis.
authors.affiliation: Department of Physical Therapy, School of Medicine, University of São Paulo, 51, São Paulo, 05360-160 SP, Brazil.
authors.forename: E V
authors.initials: EV
authors.lastname: Moderno
authors.forename: W P S
authors.initials: WP
authors.lastname: Yamaguti
authors.forename: G P P
authors.initials: GP
authors.lastname: Schettino
authors.forename: R A
authors.initials: RA
authors.lastname: Kairalla
authors.forename: M A
authors.initials: MA
authors.lastname: Martins
authors.forename: C R R
authors.initials: CR
authors.lastname: Carvalho
authors.forename: C R F
authors.initials: CR
authors.lastname: Carvalho
mesh_terms: D000368:Aged; D000886:Anthropometry; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000503:physiopathology* / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012123:Pulmonary Ventilation / Q000502:physiology*