Pulse spectroscopy system for non-invasive real-time monitoring of the heart beat volume

The left-ventricular stroke volume is an important direct indicator of the heart efficiency and perfusion of the vessels. Currently a valid measurement of the beat volume can only be implemented by invasive measurements procedures at the hospitals worldwide. Arterial catheterization is limited to intensive care unit (ICU) usage, costly and potential risky. Some available noninvasive methods yield rather an ability to track relative changes. Values delivered by these techniques are highly subjective and controversial . Enhanced pulse spectroscopy and advances in digital signal processing allow reliable measurement of the changes in peripheral blood volume with subsequent estimation of the cardiac output (CO). The aim of the current work was to design a continuous nonivasive system for the absolute monitoring of the heart beat volume (HBV). And eventually prove the validity of this new method by comparing with the standard invasive technique. It was a first trial to achieve a noninvasive measurement of the HBV by the instrumentality of a standard pulse oximeter, advanced signal processing algorithm and single individual calibration. Software algorithm has been tested on ten patients with various disorders of the cardiovascular system. The real-time absolute references of the HBV were obtained via PiCCO catheterization system (Pulsion Medical Systems, Munich, Germany) on the femoral arteries for three patients. Technology presented in this paper faces clinical needs in intensive care unit, internal medicine unit, operative, postoperative and patient recovery areas. The medical relevance of these devices is high.