title: Polysomnography in stable COPD under non-invasive ventilation to reduce patient-ventilator asynchrony and morning breathlessness.
abstract: BACKGROUND
  Stable severe chronic obstructive pulmonary disease (COPD) patients with chronic hypercapnic respiratory failure treated by nocturnal bi-level positive pressure non-invasive ventilation (NIV) may experience severe morning deventilation dyspnea. We hypothesised that in these patients, progressive hyperinflation, resulting from inappropriate ventilator settings, leads to patient-ventilator asynchrony (PVA) with a high rate of unrewarded inspiratory efforts and morning discomfort.
  
  
  METHODS
  Polysomnography (PSG), diaphragm electromyogram and transcutaneous capnography (PtcCO(2)) under NIV during two consecutive nights using baseline ventilator settings on the first night, then, during the second night, adjustment of ventilator parameters under PSG with assessment of impact of settings changes on sleep, patient-ventilator synchronisation, morning arterial blood gases and morning dyspnea.
  
  
  RESULTS
  Eight patients (61 ± 8 years, FEV(1) 30 ± 8% predicted, residual volume 210 ± 30% predicted) were included. In all patients, pressure support was decreased during setting adjustments, as well as tidal volume, while respiratory rate increased without any deleterious effect on nocturnal PtcCO(2) or morning PaCO(2). PVA index, initially high (40 ± 30%) during the baseline night, decreased significantly after adjusting ventilator settings (p = 0.0009), as well as subjective perception of PVA leaks, and morning dyspnea while quality of sleep improved.
  
  
  CONCLUSIONS
  The subgroup of COPD patients treated by home NIV, who present marked deventilation dyspnea and unrewarded efforts may benefit from adjustment of ventilator settings under PSG or polygraphy.
authors: Division of Pulmonary Diseases, Geneva University Hospitals, Rue Gabrielle-Perret-Gentil 4, 1211, Geneva 14, Switzerland. dan.adler@hcuge.ch
authors: Dan
authors: D
authors: Adler
authors: Stephen
authors: S
authors: Perrig
authors: Hiromitsu
authors: H
authors: Takahashi
authors: Fabrice
authors: F
authors: Espa
authors: Daniel
authors: D
authors: Rodenstein
authors: Jean Louis
authors: JL
authors: Pépin
authors: Jean-Paul
authors: JP
authors: Janssens
mesh_terms: D000368:Aged; D001785:Blood Gas Monitoring, Transcutaneous; D002940:Circadian Rhythm / Q000502:physiology*; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D004417:Dyspnea / Q000503:physiopathology* / Q000517:prevention & control*; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood*; D017286:Polysomnography / Q000379:methods*; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology* / Q000628:therapy*; D012984:Software; D013557:Switzerland; D013813:Therapy, Computer-Assisted / Q000379:methods*; D014851:Wakefulness / Q000502:physiology
chemical_list: D010100:Oxygen