title: Cardiac and respiratory effects of continuous positive airway pressure and noninvasive ventilation in acute cardiac pulmonary edema.
abstract: OBJECTIVE
  Continuous positive airway pressure (CPAP) is considered an effective nonpharmacologic method of treating patients with severe acute cardiogenic pulmonary edema. However, we hypothesized that bilevel noninvasive positive-pressure ventilation (NPPV), which combines both inspiratory pressure support and positive expiratory pressure, would unload the respiratory muscles and improve cardiac and hemodynamic function more effectively than CPAP.
  
  
  METHODS
  Randomized crossover study.
  
  
  METHODS
  Critical care unit, Raymond Poincaré Hospital.
  
  
  METHODS
  Six consecutive patients with acute cardiogenic pulmonary edema.
  
  
  METHODS
  Patients were sequentially treated with 5 cm H2O CPAP, 10 cm H2O CPAP, and NPPV in a random order.
  
  
  RESULTS
  Cardiac and hemodynamic function and indexes of respiratory mechanics were measured at each treatment sequence. NPPV reduced the esophageal pressure swing and esophageal pressure-time product compared with baseline (p <.05). There was no reduction in esophageal pressure swing or esophageal pressure-time product with CPAP. NPPV and 10 cm H2O CPAP reduced the mean transmural right and left atrial filling pressures without a change in cardiac index.
  
  
  CONCLUSIONS
  This study demonstrates that NPPV was more effective at unloading the respiratory muscles than CPAP in acute cardiogenic pulmonary edema. In addition, NPPV and 10 cm H2O CPAP produced a reduction in right and left ventricular preload, which suggests an improvement in cardiac performance.
authors.affiliation: Service de Réanimation Médicale, Hôpital Raymond Poincaré, Gauches, France.
authors.forename: Karim
authors.initials: K
authors.lastname: Chadda
authors.forename: Djillali
authors.initials: D
authors.lastname: Annane
authors.forename: Nicholas
authors.initials: N
authors.lastname: Hart
authors.forename: Philippe
authors.initials: P
authors.lastname: Gajdos
authors.forename: Jean Claude
authors.initials: JC
authors.lastname: Raphaël
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lofaso
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018592:Cross-Over Studies; D005260:Female; D006331:Heart Diseases / Q000628:therapy*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D011654:Pulmonary Edema / Q000628:therapy*; D015656:Respiratory Mechanics; D016037:Single-Blind Method; D018709:Statistics, Nonparametric