title: Airway humidification in mechanically ventilated neonates and infants: a comparative study of a heat and moisture exchanger vs. a heated humidifier using a new fast-response capacitive humidity sensor.
abstract: OBJECTIVE
  To study the efficiency of a heated humidifier and a heat and moisture exchanger in mechanically ventilated neonates and infants.
  
  
  METHODS
  Prospective, controlled, clinical study.
  
  
  METHODS
  University pediatric intensive care unit.
  
  
  METHODS
  Forty neonates and infants who needed mechanical ventilation were enrolled in the study.
  
  
  METHODS
  None.
  
  
  RESULTS
  A heat and moisture exchanger and active airway humidification were alternately used in the same patients to exclude interindividual differences in airway humidification. Airway humidity was measured by a new fast-response capacitive humidity sensor which measures airway humidity with an acquisition rate of 20 Hz throughout the respiratory cycle. The humidity sensor was placed at the endotracheal tube adapter. Measurements were done at the beginning and at the end of three consecutive sessions of passive, active, and again passive airway humidification, each session lasting 6 hrs. There was no significant difference between mean inspiratory airway humidity with the heated humidifier (33.8 +/- 2.9 mg/L) and with the heat and moisture exchanger (34.0 +/- 2.6 mg/L). Moreover, the mode of airway humidification did not significantly influence body temperature or PCO2. No serious side effects such as endotracheal tube occlusion were observed.
  
  
  CONCLUSIONS
  Passive airway humidification by a heat and moisture exchanger is effective in mechanically ventilated neonates and infants over a 6-hr period. However, the performance and safety of a heat and moisture exchanger in prolonged mechanical ventilation remain to be proven.
authors.affiliation: Department of Pediatrics, University of Göttingen, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Schiffmann
authors.forename: J
authors.initials: J
authors.lastname: Rathgeber
authors.forename: D
authors.initials: D
authors.lastname: Singer
authors.forename: K
authors.initials: K
authors.lastname: Harms
authors.forename: A
authors.initials: A
authors.lastname: Bolli
authors.forename: K
authors.initials: K
authors.lastname: Züchner
mesh_terms: D003365:Costs and Cost Analysis; D004867:Equipment Design; D005858:Germany; D006358:Hot Temperature / Q000627:therapeutic use*; D006801:Humans; D006813:Humidity; D007186:Incubators, Infant; D007223:Infant; D007231:Infant, Newborn; D011446:Prospective Studies; D013997:Time Factors; D012122:Ventilators, Mechanical / Q000009:adverse effects / Q000191:economics / Q000706:statistics & numerical data