Correlation between central venous oxygen saturation and oxygen delivery changes following fluid therapy

• Published in: Acta anaesthesiologica Scandinavica 2008-10, Vol.52 (9), p.1213-1217
• Main Authors: YAZIGI, A., ABOU-ZEID, H., MADI-JEBARA, S., HADDAD, F., HAYEK, G., JABBOUR, K.
• Format: Article
• Language: English
• Subjects: Anesthesia; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Female; Fluid Therapy; Humans; Male; Medical sciences; Oxygen - blood; Veins - metabolism
• ISSN: 0001-5172; 1399-6576
• DOI: 10.1111/j.1399-6576.2008.01761.x

Background: The rationale for using central venous oxygen saturation (ScvO2) in various clinical scenarios is that it reflects the balance between oxygen delivery (DO2) and demands. In this study, we evaluated the correlation between ScvO2 and DO2 changes (ΔDo2, ΔScvO2) in patients receiving fluid therapy following coronary surgery. We also correlated the changes of mean arterial pressure (ΔMAP) and central venous pressure (ΔCVP), with ΔDO2. Methods: Sixty consecutive sedated and mechanically ventilated adult patients, with cardiac index ≤2.3 L/min/m2 and a pulmonary artery occlusion pressure ≤12 mmHg following coronary surgery, were included. Concomitant hemodynamic parameters, arterial and venous blood gases were measured before (T0) and after (T1) administration of a 500 ml bolus of an isotonic crystalloid solution over 30 min. The correlations between ΔDO2 and ΔScvO2, ΔMAP or ΔCVP were evaluated by linear regression analysis and Pearson test. Results: Cardiac index (1.9±0.2 vs 2.3±0.5 ml/min/m2), MAP (83±11 vs 94±13mmHg) and CVP (5.7±3 vs 7.1±3 mmHg) were significantly higher at T1 compared with T0. The correlation of ΔDO2 with ΔScvO2 was positive, significant (r=0.41; P=0.004) and superior to its correlation with ΔMAP (r=0.30; P=0.01) or ΔCVP (r=0.03; P=0.78). Conclusion: A significant correlation between ScvO2 and DO2 changes was found in patients receiving fluid therapy following coronary surgery. ScvO2 could be used as an indicator to track DO2 and to guide volume loading.