title: Pulse pressure variation as a predictor of fluid responsiveness during one-lung ventilation for lung surgery using thoracotomy: randomised controlled study.
abstract: OBJECTIVE
  Pulse pressure variation (PPV) is increasingly advocated as a predictor of fluid responsiveness in patients receiving mechanical ventilation. However, the ability of PPV has never been studied during one-lung ventilation (OLV). Therefore, we evaluated the value of PPV to predict fluid responsiveness in patients receiving conventional and protective OLV using receiver operating characteristic (ROC) analysis, respectively.
  
  
  METHODS
  Forty-nine patients undergoing lung surgery requiring OLV were enrolled in this study. Patients were randomised either to group P [patients receiving protective OLV with tidal volume 6 ml kg, inspired oxygen fraction (FIO2) of 0.5 and positive end-expiratory pressure (PEEP) of 5 cmH2O) or group C (patients receiving conventional OLV with tidal volume of 10 ml kg, FIO2 of 1.0 and no PEEP). Following OLV, PPV and cardiac output were measured before and 12 min after fluid loading (7 ml kg hydroxyethyl starch 6%). Patients whose cardiac indices increased by at least 15% to fluid loading were defined as the responders.
  
  
  RESULTS
  The areas under ROC curve for PPV were 0.857 (P = 0.006) in group P and 0.524 (P = 0.839) in group C, respectively. The optimal threshold value given by ROC analysis for PPV was 5.8% in group P.
  
  
  CONCLUSIONS
  PPV could predict fluid responsiveness only during protective OLV, but not conventional OLV. PPV would be helpful for fluid management in patients receiving protective OLV for lung surgery using thoracotomy.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Korea.
authors.forename: Jong-Hwan
authors.initials: JH
authors.lastname: Lee
authors.forename: Yunseok
authors.initials: Y
authors.lastname: Jeon
authors.forename: Jae-Hyon
authors.initials: JH
authors.lastname: Bahk
authors.forename: Nam-Su
authors.initials: NS
authors.lastname: Gil
authors.forename: Deok Man
authors.initials: DM
authors.lastname: Hong
authors.forename: Jun Hyun
authors.initials: JH
authors.lastname: Kim
authors.forename: Hyun Joo
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002302:Cardiac Output; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage; D008168:Lung / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D011175:Positive-Pressure Respiration; D012372:ROC Curve; D012121:Respiration, Artificial / Q000379:methods*; D013908:Thoracotomy / Q000379:methods*; D013990:Tidal Volume
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D010100:Oxygen