title: Prolonged pulmonary support after cardiac surgery: incidence, risk factors and outcomes: a retrospective cohort study.
abstract: BACKGROUND
  Post-cardiac surgery pulmonary dysfunction may be underreported. Therefore, we evaluated associated risk factors for prolonged pulmonary support after cardiac surgery.
  
  
  METHODS
  We conducted a retrospective, observational study of consecutive patients undergoing coronary artery bypass grafting or coronary artery bypass grafting plus valve repair/replacement between Jan 1, 2005, and Dec 31, 2010, at an academic medical center. Using multivariate logistic regression and Cox proportional hazards modeling, we identified risk factors associated with prolonged mechanical ventilation and supplemental O2 support as well as in-hospital mortality.
  
  
  RESULTS
  Overall, 33% (1298/3881) of patients required more than 2 days of mechanical ventilation and/or more than 5 days of supplemental O2 (prolonged support). Independent risk factors included age, weight, pre-existing lung disease, cardiac or renal dysfunction, emergent status, transfusion and cardiopulmonary bypass duration. Prolonged support was associated with increased mortality (OR, 4.75; 95% CI, 2.95-7.95; P < .001). Radiological evidence of persistent pulmonary edema 2 days after surgery was found in 4% of controls and 27% of prolonged support cases.
  
  
  CONCLUSIONS
  We identified risk factors for prolonged mechanical ventilation and supplemental O2 use, described an association with increased adverse outcomes, and determined that persistent pulmonary edema on day 2 was the most likely radiological finding.
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710. Electronic address: Raquel.Bartz@dm.duke.edu.
authors.forename: Raquel R
authors.initials: RR
authors.lastname: Bartz
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710.
authors.forename: Renata G
authors.initials: RG
authors.lastname: Ferreira
authors.affiliation: Department of Thoracic Surgery, Duke University Medical Center, Durham, NC 27710.
authors.forename: Jacob N
authors.initials: JN
authors.lastname: Schroder
authors.affiliation: Department of Respiratory Therapy, Duke University Medical Center, Durham, NC 27710.
authors.forename: John
authors.initials: J
authors.lastname: Davies
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710.
authors.forename: Wen-Wei
authors.initials: WW
authors.lastname: Liu
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710.
authors.forename: Andre
authors.initials: A
authors.lastname: Camara
authors.affiliation: Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Welsby
mesh_terms: D000368:Aged; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D016022:Case-Control Studies; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010100:Oxygen; D012120:Respiration Disorders / Q000209:etiology*; D012121:Respiration, Artificial / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D010100:Oxygen
keywords: Cardiac surgery; Cardiopulmonary bypass; Epidemiology; Lung injury; Respiratory support