Hemolab: a custom built diagnostic tool for non-invasive, synchronized recording and real-time monitoring of a Doppler spectrogram, an electrocardiogram and arterial tonometry

In clinical diagnostic practice, various medical devices are designed for specific investigations and have no margin for adding other input signals or profound post-processing. Although information obtained from these signals separately is useful, using them in a combined way allows for a more profound analysis of the cardiovascular system. Our goal was to build an affordable, compact and easy-to-use diagnostic tool enabling a synchronized acquisition of arterial pressure and flow waveforms, combined with an electrocardiogram (ecg), all in non-invasive way and to be used in a routine diagnostic setting without prolonging testing protocols or adding discomfort to the patient. The combination of the beat-to-beat pressure and velocity information allows to calculate hemodynamic parameters that can quantify mechanical characteristics of the arterial system such as compliance and resistance. In this study, we used an applanation tonometer, an ecg recorder and an ultrasound device. We built a handy diagnostic tool called Hemolab that can combine the output of several stand-alone medical monitoring devices. A synchronized acquisition of a Doppler spectrogram, an electrocardiogram and a continuous pressure signal could already be acquired non-invasively, monitored in real-time and saved for later processing. This work contributes to obtain diagnostic information from non-invasive hemodynamical parameter analysis.