title: Prediction of arterial oxygen tension during one-lung ventilation: analysis of preoperative and intraoperative variables.
abstract: OBJECTIVE
  To determine whether currently available preoperative and intraoperative variables related to arterial oxygen tension (PaO(2)) can be used as predictors for low PaO(2) during one-lung ventilation (OLV).
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  Primary university hospital.
  
  
  METHODS
  Adult patients (n = 92) undergoing thoracic surgery requiring OLV.
  
  
  METHODS
  Preoperative and intraoperative data, including past medical history, physical examination, and usual preoperative and intraoperative tests, were collected and used as explanatory variables for PaO(2) during OLV by univariate and multivariate analysis. A stepwise logistic regression including the same independent variables was used to identify patients who should be expected to develop arterial hypoxemia (PaO(2) <70 mmHg). Arterial blood gas samples were analyzed 15 minutes after the onset of OLV and after thoracotomy to determine the lowest PaO(2) value during OLV.
  
  
  RESULTS
  Preoperative (age, hematocrit, relative perfusion of the nondependent lung) and intraoperative (PaO(2) during 2-lung ventilation and mean arterial pressure at the lowest PaO(2)) variables were identified as independent factors affecting PaO(2) in OLV. PaO(2) during 2-lung ventilation was the only independent variable accounting for arterial hypoxemia when multivariate logistic regression was performed.
  
  
  CONCLUSIONS
  The PaO(2) during OLV can be predicted using routinely available preoperative and intraoperative data. From a clinical point of view, this study failed to identify patients at risk of arterial hypoxemia when OLV is instituted because mainly intraoperative independent variables are involved in the decrease of PaO(2) in this situation.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Hôpital Européen Georges Pompidou, Paris, France. tguenoun@invivo.edu
authors.forename: Thierry
authors.initials: T
authors.lastname: Guenoun
authors.forename: Didier
authors.initials: D
authors.lastname: Journois
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Silleran-Chassany
authors.forename: Jerôme
authors.initials: J
authors.lastname: Frappier
authors.forename: Nicola
authors.initials: N
authors.lastname: D'attellis
authors.forename: Antoinette
authors.initials: A
authors.lastname: Salem
authors.forename: Denis
authors.initials: D
authors.lastname: Safran
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D000768:Anesthesia, General; D001794:Blood Pressure; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010100:Oxygen / Q000097:blood*; D011446:Prospective Studies; D012044:Regression Analysis; D012121:Respiration, Artificial / Q000379:methods; D015656:Respiratory Mechanics; D019616:Thoracic Surgical Procedures
chemical_list: D010100:Oxygen