Multicentre study on peri- and postoperative central venous oxygen saturation in high-risk surgical patients

Introduction Low central venous oxygen saturation (ScvO(2)) has been associated with increased risk of postoperative complications in high-risk surgery. Whether this association is centre-specific or more generalisable is not known. The aim of this study was to assess the association between peri- and postoperative ScvO(2) and outcome in high-risk surgical patients in a multicentre setting. Methods Three large European university hospitals ( two in Finland, one in Switzerland) participated. In 60 patients with intra-abdominal surgery lasting more than 90 minutes, the presence of at least two of Shoemaker's criteria, and ASA (American Society of Anesthesiologists) class greater than 2, ScvO(2) was determined preoperatively and at two hour intervals during the operation until 12 hours postoperatively. Hospital length of stay (LOS) mortality, and predefined postoperative complications were recorded. Results The age of the patients was 72 +/- 10 years ( mean +/- standard deviation), and simplified acute physiology score SAPS II) was 32 +/- 12. Hospital LOS was 10.5 ( 8 to 14) days, and 28-day hospital mortality was 10.0%. Preoperative ScvO(2) decreased from 77% +/- 10% to 70% +/- 11% ( p < 0.001) immediately after surgery and remained unchanged 12 hours later. A total of 67 postoperative complications were recorded in 32 patients. After multivariate analysis, mean ScvO(2) value (odds ratio [OR] 1.23 [95% confidence interval (CI) 1.01 to 1.50], p = 0.037), hospital LOS (OR 0.75 [95% CI 0.59 to 0.94], p = 0.012), and SAPS II (OR 0.90 [95% CI 0.82 to 0.99], p = 0.029) were independently associated with postoperative complications. The optimal value of mean ScvO(2) to discriminate between patients who did or did not develop complications was 73% ( sensitivity 72%, specificity 61%). Conclusion Low ScvO(2) perioperatively is related to increased risk of postoperative complications in high-risk surgery. This warrants trials with goal-directed therapy using ScvO(2) as a target in high-risk surgery patients.