title: Effects of positive end-expiratory pressure on ventilatory and oxygenation parameters during pressure-controlled one-lung ventilation.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effects of PEEP on oxygenation and airway pressures during PCV-OLV.
  
  
  METHODS
  Randomized, crossover, clinical study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  Twenty-five patients undergoing thoracotomy.
  
  
  METHODS
  During the first 5 minutes of OLV, all patients were ventilated with VCV (PEEP: 0) (VCV-ZEEP). Afterward, ventilation was changed to PCV with PEEP: 0 (PCV-ZEEP) or PEEP: 4 cmH2O (PCV-PEEP) for 20 minutes. In the following 20 minutes, PCV-PEEP and PCV-ZEEP were applied in reverse sequence.
  
  
  RESULTS
  At the end of VCV-ZEEP airway pressures (peak airway pressure, plateau airway pressure, mean airway pressure, and pause airway pressure) were recorded. At the end of PCV-PEEP and PCV-ZEEP airway pressures, PaO2 and Qs/Qt were recorded. Ppeak and Pplat were significantly lower with PCV-PEEP compared with VCV-ZEEP (eg, Ppeak: 33.4+/-4.2, 28.3+/-4.1, and 28.9+/-3.7 cmH2O in VCV-ZEEP, PCV-ZEEP, and PCV-PEEP, respectively; p<0.05 for PCV-ZEEP v VCV-ZEEP and PCV-PEEP v VCV-ZEEP). PCV-PEEP was associated with an increased PaO2 (230.3+/-69.8 v 189.0+/-54.8 mmHg, p<0.05) and decreased Qs/Qt (33.4%+/-7.3% v 38.4%+/-5.7%, p<0.05) compared with PCV-ZEEP (mean+/-SD). Eighty-eight percent of the patients have benefited from PEEP.
  
  
  CONCLUSIONS
  During OLV, PCV with a low level of PEEP leads to improved oxygenation with lower airway pressures.
authors.affiliation: Department of Anaesthesiology, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey. senturkem@superonline.com
authors.forename: N Mert
authors.initials: NM
authors.lastname: Sentürk
authors.forename: Ahmet
authors.initials: A
authors.lastname: Dilek
authors.forename: Emre
authors.initials: E
authors.lastname: Camci
authors.forename: Evren
authors.initials: E
authors.lastname: Sentürk
authors.forename: Mukadder
authors.initials: M
authors.lastname: Orhan
authors.forename: Mehmet
authors.initials: M
authors.lastname: Tuğrul
authors.forename: Kamil
authors.initials: K
authors.lastname: Pembeci
mesh_terms: D000368:Aged; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000379:methods*; D012123:Pulmonary Ventilation / Q000502:physiology*