Real-time Myocardial Oximetry-Preclinical Monitoring Device Validation in a Porcine Beating-Heart Cardiopulmonary Bypass Model.

PURPOSE: Continuous, real-time monitoring of myocardial oxygenation during cardiac surgery holds potential for enhancing patient safety and improving outcomes. This study evaluated the precision of the near-infrared spectroscopy-based SpectroCor Ltd monitoring device, which measures myocardial hemoglobin/myoglobin (Hb/Mb) oxygen saturation and cytochrome c oxidase (CcO) oxidation ratio. DESCRIPTION: Yorkshire pigs, under general anesthesia, were subjected to cardiopulmonary bypass to generate graded myocardial desaturation. Graded desaturation at aortic root was induced by mixing oxygenated blood from partly pumping cardiopulmonary bypass with deoxygenated blood passing nonventilated lungs. SpectroCor myocardial oximetry was validated against blood samples drawn simultaneously from the aortic root and coronary sinus during various stable saturation intervals. EVALUATION: With accuracy of 5.3 percentage points, the SpectroCor device's myocardial Hb/Mb oxygen saturation readings tightly correlated with reference blood samples. Concurrent changes in CcO oxidation ratio closely mirrored Hb/Mb saturation, indicating reliable assessment of mitochondrial function. CONCLUSIONS: The SpectroCor monitoring device provides accurate, real-time measurements of myocardial oxygenation, supporting its potential to help optimize cardioprotective strategies during cardiac surgery.