Improvement of oscillometric blood pressure estimates through suppression of breathing effects

Abstract

This paper addresses the suppression of the effects of the breathing signal from short duration oscillometric waveform (OMW) recordings to obtain improved blood pressure estimates. As the amplitude modulating effects due to the breathing signal are multiplicative in nature, homomorphic filtering is done on the OMW. An adaptive filtering methodology is adopted to suppress the breathing signal from the OMW. For suppressing the breathing signal, an adaptive noise canceller (ANC) scheme is used when simultaneously acquired reference electrocardiogram (ECG) signal is available while an adaptive line enhancer (ALE) scheme is used when such a reference signal is not readily available. Existing algorithms are used for estimating the blood pressure values. After the suppression of the breathing effects, an improvement in the pressure estimates is observed. Unlike the current methodologies for suppressing the breathing effects from blood pressure measurements, the ALE scheme used in this paper does not require an additional reference signal.