title: Determination of Lung Volume and Hemodynamic Changes During High-Frequency Ventilation Recruitment in Preterm Neonates With Respiratory Distress Syndrome.
abstract: OBJECTIVE
  To evaluate the changes in end-expiratory lung volume during an oxygenation-guided stepwise recruitment procedure in elective high-frequency ventilation. We hypothesized that high continuous distending pressure impedes pulmonary blood flow as evidenced by reduced lung volume measurements using respiratory inductive plethysmography. Changes in oxygenation, ventilation, and peripheral perfusion were evaluated as secondary outcomes.
  
  
  METHODS
  A prospective, single center, observational, nonrandomized study.
  
  
  METHODS
  The study was conducted in a neonatal ICU in Italy.
  
  
  METHODS
  High-frequency ventilated preterm infants with respiratory distress syndrome.
  
  
  METHODS
  During the recruitment procedure, end-expiratory lung volume measured by respiratory inductive plethysmography, oxygen saturation, perfusion index, regional cerebral and perirenal tissue oxygenation, heart rate, transcutaneous PCO2, and tidal volume were simultaneously recorded at each airway pressure step.
  
  
  RESULTS
  In 12 preterm newborns (gestational age, 27.4 ± 0.2 wk; birth weight, 979 ± 198 g), high-frequency ventilation was initiated at a continuous distending pressure of 10 cm H2O and incrementally increased by 1-2 cm H2O every 2-5 minutes until FIO2 was less than or equal to 0.25. End-expiratory lung volume progressively increased during the initial recruitment, but decreased at the maximum airway pressure in nine patients, indicative of a reduction in pulmonary perfusion. At the end of recruitment, tidal volume was significantly higher (p = 0.002) and oxygenation was significantly improved (p = 0.002); however, mean perfusion index, postductal saturation, and mean renal tissue oxygenation values were significantly reduced (p < 0.05) compared with baseline. Mean cerebral tissue oxygenation and mean transcutaneous PCO2 values were reduced but failed to reach significance.
  
  
  CONCLUSIONS
  High distending lung pressures increased oxygenation but decreased peripheral perfusion with no adverse cerebral side effects. Coupled with the reduction in respiratory inductive plethysmography-derived lung volume, high continuous distending pressure had adverse cardiopulmonary effects. Incorporation of lung volume and hemodynamic and oxygenation variables may guide optimum lung volume determination during high-frequency ventilation recruitment procedure while preventing adverse effects on the pulmonary circulation.
authors: 1Division of Neonatology, Policlinico A. Gemelli-Università Cattolica del Sacro Cuore, Rome, Italy. 2The Ritchie Centre, MIMR-PHI Institute of Medical Research, Clayton, VIC, Australia. 3Department of Obstetrics and Obstetrics and Gynaecology, Monash University, Clayton, VIC, Australia.
authors: Milena
authors: M
authors: Tana
authors: Graeme R
authors: GR
authors: Polglase
authors: Francesco
authors: F
authors: Cota
authors: Chiara
authors: C
authors: Tirone
authors: Claudia
authors: C
authors: Aurilia
authors: Alessandra
authors: A
authors: Lio
authors: Cinzia
authors: C
authors: Ricci
authors: Costantino
authors: C
authors: Romagnoli
authors: Giovanni
authors: G
authors: Vento
mesh_terms: D001784:Blood Gas Analysis; D005260:Female; D006439:Hemodynamics; D006612:High-Frequency Ventilation / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007363:Intensive Care Units, Neonatal; D007558:Italy; D008176:Lung Volume Measurements; D008297:Male; D011446:Prospective Studies; D012127:Respiratory Distress Syndrome, Newborn / Q000503:physiopathology* / Q000628:therapy*; D013990:Tidal Volume