title: Feasibility of Mid-Frequency Ventilation Among Infants With Respiratory Distress Syndrome.
abstract: BACKGROUND
  Mid-frequency ventilation, a strategy of using conventional ventilators at high frequencies, may reduce lung injury but has had limited evaluation in neonates. Hence, a randomized crossover study was designed to assess the feasibility of using mid-frequency ventilation in preterm infants with respiratory distress syndrome.
  
  
  METHODS
  Twelve preterm infants (≥500 g and ≥24 weeks gestational age) who were receiving pressure-limited conventional ventilation with frequencies ≤60 breaths/min for respiratory distress syndrome were randomized to periods of mid-frequency ventilation (conventional ventilation with the fastest frequency up to 150 breaths/min that gave complete inspiration and expiration) or conventional ventilation (frequency ≤60 breaths/min), each lasting 2 h using a crossover design. Ventilator parameters were adjusted to maintain the O2saturation and transcutaneous CO2at baseline.
  
  
  RESULTS
  Mean peak inspiratory pressure (15 ± 4 cm H2O vs 18 ± 4 cm H2O,P< .001), Δ pressure (9.8 ± 3.3 cm H2O vs 13.5 ± 3.9 cm H2O,P< .001), and tidal volume (2.6 ± 0.4 mL/kg vs 4.6 ± 0.8 mL/kg,P< .001) were lower, but mean airway pressure (8.9 ± 1.9 cm H2O vs 8.4 ± 1.6 cm H2O,P= .02) and measured PEEP (5.1 ± 0.5 cm H2O vs 4.4 ± 0.5 cm H2O,P< .001) were higher with mid-frequency compared with conventional ventilation. FIO2, gas exchange, and hemodynamic parameters were not affected.
  
  
  CONCLUSIONS
  Based on this small study, mid-frequency ventilation among preterm infants with respiratory distress syndrome is feasible. Further larger and longer duration trials are necessary to validate our findings. (ClinicalTrials.gov registration NCT01242462).
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Ramachandra
authors.initials: R
authors.lastname: Bhat
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: John
authors.initials: J
authors.lastname: Kelleher
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Namasivayam
authors.initials: N
authors.lastname: Ambalavanan
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Chatburn
authors.affiliation: Cleveland Clinic, Cleveland, Ohio.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Mireles-Cabodevila
authors.affiliation: University of Alabama at Birmingham, Birmingham, Alabama. wcarlo@peds.uab.edu.
authors.forename: Waldemar A
authors.initials: WA
authors.lastname: Carlo
mesh_terms: D018592:Cross-Over Studies; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D000072277:Maximal Respiratory Pressures / Q000379:methods; D011175:Positive-Pressure Respiration / Q000379:methods; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012121:Respiration, Artificial / Q000379:methods*; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology / Q000628:therapy*; D013990:Tidal Volume / Q000502:physiology; D016896:Treatment Outcome
keywords: mechanical ventilation; preterm; respiratory distress syndrome; ventilator-induced lung injury