title: In vitro comparison of noise levels produced by different CPAP generators.
abstract: BACKGROUND
  Minimization of noise exposure is an important aim of modern neonatal intensive care medicine. Binasal continuous positive airway pressure (CPAP) generators are among the most important sources of continuous noise in neonatal wards. The aim of this study was to find out which CPAP generator creates the least noise.
  
  
  METHODS
  In an experimental setup, two jet CPAP generators (Infant Flow® generator and MediJet®) and two conventional CPAP generators (Bubble CPAP® and Baby Flow®) were compared. Noise production was measured in decibels in an A-weighted scale [dB(A)] in a closed incubator at 2 mm lateral distance from the end of the nasal prongs. Reproduction of constant airway pressure and air leak was achieved by closure of the nasal prongs with a type of adhesive tape that is semipermeable to air.
  
  
  RESULTS
  The noise levels produced by the four generators were significantly different (p < 0.001). Values measured at a continuous constant flow rate of 8 l/min averaged 83 dB(A) for the Infant Flow® generator with or without sound absorber, 72 dB(A) for the MediJet®, 62 dB(A) for the Bubble CPAP® and 55 dB(A) for the Baby Flow®.
  
  
  CONCLUSIONS
  Conventional CPAP generators work more quietly than the currently available jet CPAP generators.
authors.affiliation: Division of Neonatology, Pediatric Intensive Care and Neuropediatrics, Department of General Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.
authors.forename: Lieselotte
authors.initials: L
authors.lastname: Kirchner
authors.forename: Martin
authors.initials: M
authors.lastname: Wald
authors.forename: Valerie
authors.initials: V
authors.lastname: Jeitler
authors.forename: Arnold
authors.initials: A
authors.lastname: Pollak
mesh_terms: D045422:Continuous Positive Airway Pressure / Q000009:adverse effects* / Q000295:instrumentation*; D006801:Humans; D007231:Infant, Newborn; D015931:Intensive Care, Neonatal; D009622:Noise