title: Clinical predictors of a low central venous oxygen saturation after major surgery: a prospective prevalence study.
abstract: Optimising perioperative haemodynamic status may reduce postoperative complications. In this prospective prevalence study, we investigated the associations between standard haemodynamic parameters and a low central venous oxygen saturation (ScvO2) in patients after major surgery. A total of 201 patients requiring continuous arterial and central venous pressure monitoring after major surgery were recruited. Simultaneous arterial and central venous blood gases, haemodynamic and biochemical data and perfusion index were obtained from patients at a single time-point within 24 hours of surgery. A low ScvO2 (<70%) was observed in 109 patients (54%). Use of mechanical ventilation, mean arterial pressure, central venous pressure, haemoglobin concentrations, arterial pH and lactate concentrations, arterial oxygen (PaO2) and carbon dioxide tensions (PaCO2) were all associated with a low ScvO2 in the univariate analyses. In the multivariate analysis, only a higher perfusion index (odds ratio [OR] 0.87, 95% confidence interval [CI] 0.78 to 0.98), PaO2 (OR 0.98 per mmHg increment, 95% CI 0.97 to 0.99) and PaCO2 (OR 0.88 per mmHg increment, 95% CI 0.82 to 0.95) and a lower central venous pressure (OR 1.14 per mmHg increment, 95% CI 1.04 to 1.25) were significantly associated with a reduced risk of a low ScvO2, all in a linear fashion. In conclusion, PaO2, PaCO2, perfusion index and central venous pressure were significant predictors of a low ScvO2 in patients after major surgery including cardiac surgery.
authors.affiliation: Department of Intensive Care Medicine, Royal Perth Hospital and School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia.
authors.forename: E
authors.initials: E
authors.lastname: Litton
authors.affiliation: Department of Intensive Care Medicine, Royal Perth Hospital, Perth, Western Australia.
authors.forename: B
authors.initials: B
authors.lastname: Silbert
authors.affiliation: Department of Intensive Care Medicine, Royal Perth Hospital and School of Population Health, University of Western Australia, Perth, Western Australia.
authors.forename: K M
authors.initials: KM
authors.lastname: Ho
mesh_terms: D000368:Aged; D062186:Arterial Pressure / Q000502:physiology; D001784:Blood Gas Analysis / Q000379:methods; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods*; D016017:Odds Ratio; D010100:Oxygen / Q000097:blood*; D011183:Postoperative Complications / Q000097:blood*; D015995:Prevalence; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000379:methods; D013514:Surgical Procedures, Operative
chemical_list: D002245:Carbon Dioxide; D019344:Lactic Acid; D010100:Oxygen
keywords: central venous oxygen saturation; haemodynamic targets; oxygenation; perioperative period; prediction