Cerebral Oxygen Desaturation in Patients with Totally Thoracoscopic Ablation for Atrial Fibrillation

Abstract

Background: Epicardial radiofrequency ablation for atrial fibrillation under total video-assisted thoracoscopy causes severe cardiopulmonary disturbances and affects cerebral perfusion and oxygenation. The aim of the present study was to investigate the changes in regional cerebral oxygen saturation (rSO2) during the surgery and their correlations with hemodynamic or blood gas parameters. Methods: A total of 45 patients scheduled for selective totally thoracoscopic ablation for stand-alone atrial fibrillation were enrolled in this study. The rSO2 was monitored at baseline (T0), 15 min after anesthesia induction (T1), 15 min after one-lung ventilation (T2), after right pulmonary vein ablation (T3), after left pulmonary vein ablation (T4) and 15 min after two-lung ventilation (T5) using a near-infrared reflectance spectroscopy (NIRS)-based cerebral oximeter. A Swan-Ganz catheter was placed in the pulmonary artery to obtain hemodynamic parameters. Arterial blood gas was analyzed using an ABL 825 hemoximeter. Associations between changes in rSO2 (△rSO2) and hemodynamic or blood gas parameters were determined with univariate and multivariate linear regression analyses. Results: The rSO2 decreased greatly from baseline 65.3% to 57.5% at T3 (P < 0.001). Univariate analysis showed that △rSO2 correlated significantly with △pH (r = -0.371, P = 0.012), △PaCO2 (r = -0.276, P = 0.066), △PaO2/FiO2 (r = 0.332, P = 0.026), △HR (r = 0.27, P = 0.073), △CI (r = -0.228, P = 0.132) and △PVRI/SVRI (r = -0.216, P = 0.153). Multivariate linear regression analysis further showed that △rSO2 was only influenced by △PaO2/FiO2 (β = 0.026, P = 0.025). Conclusion: The rSO2 decreased significantly during the totally thoracoscopic ablation for atrial fibrillation. There was a correlation between rSO2 reduction and PaO2/FiO2 changes. Greater attention should be paid to cerebral oxygen desaturation during the surgery.

Effects on Cerebral Oxygen Balance in Coronary Artery Bypass Grafting: A Comparison of Conventional and Minimal Extracorporeal Circulation

“…To our knowledge, this is the first exploration focused on cerebral oxygen balance with different extracorporeal circulation techniques. Since NIRS-baseed cerebral oximeter detects rSO 2 with several flaws, we believed indirectly observing cerebral oxygen through hemodynamics and blood gas tests might be more easy-operating and overall reflected, as evidence showed strong correlation with indicators like rSO 2 and MAP, PaO 2 and BE [18][19][20][21].…”

“…It is reported that patients with a MAP maintaining at 70-90 mmHg during CABG surgery had better prognosis than those at 50-70 mmHg [28]. MAP maintaining at 60-90 mmHg could avoid hypoperfusion cerebral ischemia and ensure cerebral oxygen supply [20,29]. The reduced blood dilution with MECC led to a higher hematocrit during the entire CPB period, ensuring sufficient oxygen supply to the brain and other vital organs.…”

“…In normal patients, bilateral jugular bulb saturations are equal and probably represent drainage from all parts of the brain [25,26]. Continuous monitoring of the jugular venous oxygen saturation (SjvO 2 ), which is sampled from this position, can be used as an indicator of cerebral oxygenation (20)(21)(22) for accuracy, the catheterization is performed as previously described [27]. A 5F double-lumen central venous catheter (Yixinda, Shenzhen, China) is carefully placed in the right jugular vein towards the brain.…”

“…Regional cerebral oxygen saturation (rSO 2 ) obtained from a near-infrared reflectance spectroscopy (NIRS) was proved to be correlated significantly with heart rate, mean artery pressure (MAP), central venous pressure, arterial carbon dioxide tension, arterial oxygen pressure, and base excess (BE); and is correlated positively with PaO 2 , MAP, and BE [18,19]. As the NIRS-based cerebral oximeter only detect oxygen saturation in a thin superficial layer, it can neither measure global cerebral oxygenation, nor differentiate between arterial and venous blood [20]. In this work, we investigated the cerebral oxygen balance impact brought by MECC, compared the cerebral oxygen balance by monitoring a variety of indicators in patients who underwent coronary artery bypass grafting with these CPB technologies [21].…”