The CritiView (CRV) Real-time Optical Monitoring System for Mitochondrial Function and Tissue Vitality: From Bench to Bedside

Abstract

The involvement of mitochondria in pathological states, such as neurodegenerative diseases, sepsis, stroke, and cancer, is well documented. Monitoring of nicotinamide adenine dinucleotide (NADH) fluorescence in vivo as an intracellular oxygen indicator was established in 1950 to 1970 by Britton Chance and collaborators. However, the monitoring of mitochondrial function in real time in vivo is not commonly employed in clinical monitoring. This study aims to evaluate mitochondrial function and tissue vitality using a Real-time Optical Monitoring System. A multiparametric monitoring system enabling assessment of tissue vitality was used. In order to use this technology in clinical practice, the commercially developed device, the CritiView (CRV), is tested in animal models as well as in patients. For this investigation, 35 male rats (250–300 gr) and 25 Mongolian gerbils (50–75 gr) were used for the various in vivo studies. The new CRV enables the optical monitoring of four different parameters, representing the energy balance of various tissues in vivo. Mitochondrial NADH is measured by surface fluorometry/reflectometry. In addition, tissue microcirculatory blood flow, tissue reflectance and oxygenation are measured as well. The device is tested both in vitro and in vivo in a small animal model and in preliminary clinical trials in patients undergoing vascular or open heart surgery. In patients, the monitoring is started immediately after the insertion of a three-way Foley catheter (urine collection) to the patient and is stopped when the patient is discharged from the operating room. Data analysis was performed using regression analysis for in vitro tests and ANOVA for in vivo monitoring. The results show that monitoring the urethral wall vitality provides information in correlation with the surgical procedure performed. This study concludes that the CritiView results may serve as early warning signals to the deterioration of the body or the endpoint of resuscitation during and after cardiovascular surgeries. A large-scale clinical study with positive results may open up a new era in the monitoring of critical care patients.