title: High central venous saturation after cardiac surgery is associated with increased organ failure and long-term mortality: an observational cross-sectional study.
abstract: BACKGROUND
  Central venous saturation (ScvO2) monitoring has been suggested to address the issue of adequate cardiocirculatory function in the context of cardiac surgery. The aim of this study was to determine the impact of low (L) (<60%), normal (N) (60%-80%), and high (H) (>80%) ScvO2 measured on intensive care unit (ICU) admission after cardiac surgery.
  
  
  METHODS
  We conducted a retrospective, cross-sectional, observational study at three ICUs of a university hospital department for anaesthesiology and intensive care. Electronic patient records of all adults who underwent cardiac surgery between 2006 and 2013 and available admission measurements of ScvO2 were examined. Patients were allocated to one of three groups according to first ScvO2 measurement after ICU admission: group L (<60%), group N (60%-80%), and group H (>80%). Primary end-points were in-hospital and 3-year follow-up survival.
  
  
  RESULTS
  Data from 4,447 patients were included in analysis. Low and high initial measurements of ScvO2 were associated with increased in-hospital mortality (L: 5.6%; N: 3.3%; H: 6.8%), 3-year follow-up mortality (L: 21.6%; N: 19.3%; H: 25.8%), incidence of post-operative haemodialysis (L: 11.5%; N: 7.8%; H: 15.3%), and prolonged hospital length of stay (L: 13 days, 9-22; N: 12 days, 9-19; H: 14 days, 9-21). After adjustment for possible confounding variables, an initial ScvO2 above 80% was associated with adjusted hazard ratios of 2.79 (95% confidence interval (CI) 1.565-4.964, P <0.001) for in-hospital survival and 1.31 (95% CI 1.033-1.672, P = 0.026) for 3-year follow-up survival.
  
  
  CONCLUSIONS
  Patients with high ScvO2 were particularly affected by unfavourable outcomes. Advanced haemodynamic monitoring may help to identify patients with high ScvO2 who developed extraction dysfunction and to establish treatment algorithms to improve patient outcome in these patients.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. felix.balzer@charite.de.
authors.forename: Felix
authors.initials: F
authors.lastname: Balzer
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. michael.sander@charite.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Sander
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, Jena University Hospital, Erlanger Allee 101, 07747, Jena, Germany. mark.simon@med.uni-jena.de.
authors.forename: Mark
authors.initials: M
authors.lastname: Simon
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. claudia.spies@charite.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Spies
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. marit.habicher@charite.de.
authors.forename: Marit
authors.initials: M
authors.lastname: Habicher
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. sascha.treskatsch@charite.de.
authors.forename: Sascha
authors.initials: S
authors.lastname: Treskatsch
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. viktor.mezger@charite.de.
authors.forename: Viktor
authors.initials: V
authors.lastname: Mezger
authors.affiliation: Institute of Anaesthesiology Heart and Diabetes Center Nordrhein-Westfalen, University Clinic Ruhr-University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany. uschirmer@hdz-nrw.de.
authors.forename: Uwe
authors.initials: U
authors.lastname: Schirmer
authors.affiliation: Department of Anaesthesiology and Intensive Care Medicine, University of Lübeck, Ratzeburger Allee 160, 23538, Lübeck, Germany. heringlake@t-online.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Heringlake
authors.affiliation: SOSTANA GmbH, Wildensteiner Straße 27, 10318, Berlin, Germany. wernecke@sostana.de.
authors.forename: Klaus-Dieter
authors.initials: KD
authors.lastname: Wernecke
authors.affiliation: Department of Cardiovascular Surgery, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. herko.grubitzsch@charite.de.
authors.forename: Herko
authors.initials: H
authors.lastname: Grubitzsch
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, University Hospital Charité, Campus Charité Mitte/Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10098, Berlin, Germany. christian.von_heymann@charite.de.
authors.forename: Christian
authors.initials: C
authors.lastname: von Heymann
mesh_terms: D006348:Cardiac Surgical Procedures / Q000009:adverse effects* / Q000401:mortality; D062905:Central Venous Catheters; D003422:Critical Care / Q000592:standards*; D003430:Cross-Sectional Studies; D017052:Hospital Mortality; D006801:Humans; D010100:Oxygen / Q000009:adverse effects* / Q000378:metabolism; D011446:Prospective Studies; D012189:Retrospective Studies
chemical_list: D010100:Oxygen