Preliminary study on contactless evaluation of peripheral perfusion during rotary blood pump support

Rotary blood pumps are commonly used for circulatory support in the patients with severe heart failure. We proposed a new evaluation method of peripheral perfusions by using a charge-coupled device. There is increasing case for heart rate or pulse wave detection capabilities from the record by charge-coupled devices, such as digital cameras. In this study, we performed animal experiments in goats and examined a quantitative investigation method of peripheral circulation in the organs by a noninvasive and contactless measurement using a digital high speed camera. Measurements of peripheral blood flow in the organs were carried out in these two steps: a) the validation of the chargecoupled device detection with the laser blood flow meter in the animal experiments, and b) the examination of peripheral perfusing during a centrifugal blood pump assistance. A simple capture of the goat’s peripherals, such as the surface of kidney, lung or skins, allowed a measurement of how the RGB components were distributed within the organ peripherals. The color components of the images were obtained with the high speed still camera (Casio, EX-F1) at 300 fps. Tissue perfusion in the vicinity of the location was also measured by the laser blood flow meter (Omega Flow, FLO-C1) for validation. Then a centrifugal blood pump (Evaheart, SunMedical Technology Research Corp., Japan) was employed and we examined its effects on peripheral blood flow changes. As a result, we could obtain the pulse wave changes by the analysis of the distribution of green light histogram levels derived from the data. Therefore, it was suggested that our approach of the evaluation of peripheral blood flow distribution by a simple shot of digital cameras might achieve the evaluation of the effects of surgical treatment on peripheral organs with the rotary blood pump support.