title: [Effects of positive end-expiratory pressure on lung recruited volume and oxygenation in patients with acute respiratory distress syndrome].
abstract: OBJECTIVE
  To access alveolar recruitment with positive end-expiratory pressure (PEEP) and to correlate the recruited volume with arterial oxygenation in acute respiratory distress syndrome (ARDS).
  
  
  METHODS
  Eleven ventilated patients satisfying criteria of ARDS were included in the study group. Recruited volume of three different PEEP levels [5 cm H2O, 10 cm H2O, 15 cm H2O (1 cm H2O=0.098 kPa)] were measured by pressure-volume curve method. Effects of different PEEP levels on lung mechanics and gas exchange were compared.
  
  
  RESULTS
  Lung recruited volume elevated when PEEP increased from 5 cm H2O to 15 cm H2O[(40.2+/-15.3)ml vs. (123.8+/-43.1)ml vs. (178.9+/-43.5)ml, all P<0.05]. Arterial oxygenation index increased with PEEP and a positive correlation was found between recruited volume and changes in arterial oxygenation index (r=0.483, P<0.01). There was no significant difference during the static compliance at different PEEP levels at a fixed tidal volume (P>0.05). Recruited volume at PEEP 15 cm H2O in the patient group with lower inflection point (LIP) was larger than the group without LIP.
  
  
  CONCLUSIONS
  Recruited volume increases with PEEP, and the PEEP-induced increase in arterial oxygenation is significantly correlated to recruited volume.
authors.affiliation: Department of Critical Care Medicine, Zhongda Hospital and School of Clinical Medicine, Southeast University, Nanjing 210009, Jiangsu, China. haiboq2000@yahoo.com.cn
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Qiu
authors.forename: Hong-Yang
authors.initials: HY
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Yang
authors.forename: Shao-Xia
authors.initials: SX
authors.lastname: Zhou
authors.forename: Yong-Ming
authors.initials: YM
authors.lastname: Chen
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Sun
mesh_terms: D000328:Adult; D000368:Aged; D001784:Blood Gas Analysis; D005260:Female; D006801:Humans; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration; D012128:Respiratory Distress Syndrome / Q000097:blood / Q000503:physiopathology* / Q000628:therapy