Continuous Cuffless Blood Pressure Estimation Based on Pulse Transit Time: A New Evaluation with Invasive BP Reference*

One of the indirect approaches to obtain blood pressure (BP) values is through the so-called pulse transit time (PTT) that is the time for the cardiac wave to propagate through a length of the arterial tree or between the heart and a peripheral arterial site. In this work, we investigated the performance of four latest cuffless BP estimation methods including the method proposed in our previous work by using the invasive BP as reference. The invasive BP data was collected from 10 patients during surgery. Experimental results showed that the estimation errors from the compared methods are much larger than the 5 ± 8 mmHg limits that is required for any BP measurement method or instrument to be satisfied the requirements of the AAMI Standard. Therefore, the PTT-based BP estimation methods need to be further improved and enhanced for obtaining acceptable performance.