title: Comparison of two flow generators with a noninvasive ventilator to deliver continuous positive airway pressure: a test lung study.
abstract: OBJECTIVE
  To compare the performance of two continuous flow generators with a ventilator designed for noninvasive positive pressure ventilation (NPPV) to deliver continuous positive airway pressure (CPAP). The performance of flow generators using different oxygen pressure supplies was also compared.
  
  
  METHODS
  Experimental study using a mechanical lung model in a university research laboratory.
  
  
  METHODS
  Two flow generators supplied at 100, 200, and 300 kPa and an NPPV ventilator were compared at CPAP of 5, 10, and 15 cmH2O in: (a) area under the adjusted CPAP level during inspiration, (b) capacity to attain the preset CPAP, and (c) tidal volume.
  
  
  RESULTS
  The NPPV ventilator attained the preset CPAP better than flow generators, but its area under adjusted CPAP was similar to or higher than that of flow generators when these were adjusted to their better pressure supply. Both flow generators had better performance with an output flow around 100 l/min, which was achieved at 100 kPa with one flow generator and 300 with the other. Flow generators and the NPPV ventilator generated similar tidal volumes.
  
  
  CONCLUSIONS
  Flow generators performance showed large variations among different devices and oxygen pressure supplies. Adjusted to their better pressure supply, flow generators had a similar or better capacity to maintain the CPAP level, but the NPPV ventilator was more reliable to attain the preset CPAP. Flow generators could be an alternative to provide CPAP in low-income areas, usually with scarce medical equipment availability.
authors.affiliation: Physiotherapy, Phonology and Occupational Therapy Department, Medical School, University of São Paulo, São Paulo, Brazil.
authors.forename: Carolina
authors.initials: C
authors.lastname: Fu
authors.forename: Pedro
authors.initials: P
authors.lastname: Caruso
authors.forename: Jeanette Janaina Jaber
authors.initials: JJ
authors.lastname: Lucatto
authors.forename: Guilherme Pinto
authors.initials: GP
authors.lastname: de Paula Schettino
authors.forename: Rogério
authors.initials: R
authors.lastname: de Souza
authors.forename: Carlos Roberto Ribeiro
authors.initials: CR
authors.lastname: Carvalho
mesh_terms: D001187:Artificial Organs; D045422:Continuous Positive Airway Pressure / Q000295:instrumentation*; D008168:Lung