title: Central venous pressure after coronary artery bypass surgery: does it predict postoperative mortality or renal failure?
abstract: OBJECTIVE
  Although hemodynamic monitoring is often performed after coronary artery bypass grafting (CABG), the role of monitoring postoperative central venous pressure (CVP) measurement as a predictor of clinical outcomes is unknown. As such, this study tests the hypothesis that postoperative CVP is predictive of operative mortality or renal failure.
  
  
  METHODS
  This is an observational cohort study of detailed clinical data from 2390 randomly selected patients undergoing high-risk CABG or CABG/valve at 55 hospitals participating in the Society of Thoracic Surgeons' National Cardiac Surgery Database 2004-2005. Eligible patients underwent elective/urgent CABG with an ejection fraction less than 40% or elective/urgent CABG at 65 years or older with diabetes or a glomerular filtration rate less than 60 mL/min per 1.73 m2. The exposure of interest is CVP monitoring in the intensive care unit after adult cardiac surgery. The primary outcome measure was correlation between postoperative CVP and inhospital/30-day mortality and renal failure, assessed as a continuous variable, both unadjusted and after adjusting for important clinical factors using logistic regression modeling.
  
  
  RESULTS
  Mean age was 72 years, 54% of patients had diabetes mellitus, 49% were urgent procedures, and mean cardiopulmonary bypass time was 105 minutes. Patients' CVP 6 hours postoperation was strongly associated with inhospital and 30-day mortality: odds ratio (OR) of 1.5 (95% confidence interval [CI], 1.23-1.87) for every 5-mm Hg increase in CVP; P<.0001. This association remained significant after risk adjustment: adjusted OR of 1.44 (95% CI, 1.10-1.89); P<.01. A model adjusting for cardiac index also revealed increased incidence of mortality or renal failure: adjusted OR of 1.5 (95% CI, 1.28-1.86) for every 5-mm Hg increase in CVP; P<.0001.
  
  
  CONCLUSIONS
  Patients' CVP at 6 hours after CABG surgery was highly predictive of operative mortality or renal failure, independent of cardiac index and other important clinical variables. Future studies will need to assess whether interventions guided by postoperative CVP can improve patient outcomes.
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA; Division of Thoracic and Cardiovascular Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Judson B
authors.initials: JB
authors.lastname: Williams
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC, USA.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wojdyla
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA.
authors.forename: Ralf
authors.initials: R
authors.lastname: Harskamp
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Kevin W
authors.initials: KW
authors.lastname: Southerland
authors.affiliation: Department of Cardiovascular Sciences, Brody School of Medicine and East Carolina Heart Institute, East Carolina University, Greenville, NC, USA.
authors.forename: T Bruce
authors.initials: TB
authors.lastname: Ferguson
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Peter K
authors.initials: PK
authors.lastname: Smith
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, Department of Surgery, Duke University Medical Center, Durham, NC, USA.
authors.forename: Carmelo A
authors.initials: CA
authors.lastname: Milano
authors.affiliation: Duke Clinical Research Institute, Duke University Medical Center, Durham, NC, USA; Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC, USA. Electronic address: renato.lopes@duke.edu.
authors.forename: Renato D
authors.initials: RD
authors.lastname: Lopes
mesh_terms: D000368:Aged; D001795:Blood Pressure Determination / Q000379:methods; D002496:Central Venous Pressure / Q000502:physiology*; D015331:Cohort Studies; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000401:mortality*; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D017052:Hospital Mortality; D006801:Humans; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D011183:Postoperative Complications / Q000401:mortality*; D011184:Postoperative Period; D051437:Renal Insufficiency / Q000209:etiology*; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome
keywords: Cardiac index; Central venous pressure; Coronary artery bypass; Hemodynamic monitoring; Perioperative care; Surgery