Baseline Regional Cerebral Oxygen Saturation Correlates With Left Ventricular Systolic and Diastolic Function

Objective: To evaluate the correlation between baseline cerebral oxygen saturation (ScO₂) and cardiac function as assessed by pulmonary artery catheterization and transesophageal echocardiography (TEE). Design: A retrospective study. Setting: A tertiary care university hospital. Participants: Cardiac surgery patients. Measurements and Results: Patients undergoing cardiac surgery with bilateral recording of their baseline ScO₂ using the INVOS 4100 (Somanetics, Troy, MI) were selected. A pulmonary artery catheter was used to obtain their hemodynamic profile. Left ventricular (LV) systolic and diastolic function was evaluated by TEE, after the induction of anesthesia, using standard criteria. A model was developed to predict ScO₂. A total of 99 patients met the inclusion criteria. There were significant correlations between mean ScO₂ values and central venous pressure (CVP) (r = -0.31, p = 0.0022), pulmonary capillary wedge pressure (r = -0.25, p = 0.0129), mean pulmonary artery pressure (MPAP) (r = -0.24, p = 0.0186), mean arterial pressure/MPAP ratio (r = 0.33, p = 0.0011), LV fractional area change (<35, 35-50, and ≥50, p = 0.0002), regional wall motion score index (r = -0.27, p = 0.0062), and diastolic function (p = 0.0060). The mean ScO₂ had the highest area under the receiver operating characteristic curve (0.74; confidence interval, 0.64-0.84) to identify LV systolic dysfunction. A model predicting baseline ScO₂ was created based on LV systolic echocardiographic variables, CVP, sex, mitral valve surgery, and the use of β-blocker (r² = 0.42, p < 0.001). Conclusion: Baseline ScO₂ values are related to cardiac function and are superior to hemodynamic parameters at predicting LV dysfunction.