Oxygen Homeostasis and Mitochondrial Function in COVID-19 and ARDS Patients: The Ultimate Vital Signs

Abstract

The leading cause of death from the COVID-19 is the development of Pneumonia and Acute Respiratory Distress Syndrome-ARDS. Advanced physiological monitoring of COVID -19 patients in real time is a missing tool that avoid the optimization of better diagnosis and evaluating the efficacy of the treatment given. As of today, the monitoring of the systemic vital signs provides important information regarding the respiratory and cardiovascular systems including the pulse oximetry that provide data on hemoglobin oxygenation in the macro circulation. Our hypothesis is that the pathophysiology of COVID-19 and ARDS patients includes severe changes in the microcirculatory hemodynamics and cellular disturbances in Tissue and cellular Oxygen Homeostasis. Therefore, we postulate that real time monitoring of mitochondrial NADH redox state and microcirculatory blood flow, volume and hemoglobin oxygenation is the missing information that will affect dramatically the outcome of COVID-19 and ARDS patients. During the last 2 decades we studied the mechanism of blood flow redistribution activated in animal models as well as in patients exposed to total body negative oxygen balance. This mechanism is activated by the sympathetic pathway. This effect is not equal in all organs of the body, namely, in the most vital organs - brain, heart, and adrenal glands oxygen supply is preserved while in the less vital organs (visceral and peripheral organs) hypo perfusion and negative oxygen balance is recorded. In order to evaluate the tissue oxygen homeostasis, we developed a new concept named - LifenLight Score (LLS)TM based on the monitoring of four physiological parameters measured in real time from one of the less vital organs in the body. Our developed device is monitoring mitochondrial function by measuring the NADH auto fluorescence and microcirculatory blood flow, tissue reflectance and hemoglobin oxygenation. In animal model we monitored simultaneously the brain and the small intestine. In patients we used a 3-way Foley catheter introduced to the bladder via the urethra. We found that monitoring the less vital organ could serve as an early warning signal to the development of negative oxygen balance in the body as well as indicate of a recovery process in the improvement of the oxygen balance homeostasis. In conclusion, we hypothesize that using our new monitoring system will be able to detect deterioration process related to hypoxia in COVID-19 and ARDS patients, as well as to monitor improvement in tissue oxygen balance due to various treatments such as exposure to hyperoxia.