Session PB6.3

Detection of Mean Arterial Pressure Dropping Regimes during Acute Hypotensive Episodes

A Ghaffari, MR Homaeinezhad*, M Atarod, M Akraminia, R Rahmani

K. N. Toosi University of Technology
Tehran, Iran

The presented study concentrates on the detection of Acute Hypotensive Episodes (AHE) and MAP (Mean Arterial Pressure) Dropping Regimes (MAPDRs) on the basis of ECG signal and Arterial Blood Pressure (ABP) waveform measurements. To meet this end, the QRS complexes and end-systolic end-diastolic pulses are first identified using two versions of the Modified Hilbert Transform algorithm namely as ECGMHT and BPMHT, respectively. Then, using the obtained Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) waveforms, MAP trend is specified. Afterwards, in order to smooth the fast fluctuations observed in RR-tachogram and MAP trend, we have designed an innovative smoothing algorithm based on piecewise polynomial fitting (PPF). Fitting N numbers of polynomials sequentially to the original signal and determination of the corresponding coefficients based on the Best Linear Unbiased Estimation (BLUE) approach (Ghaffari et al., 2008) is the basis of the PPF algorithm operation. Finally, the proposed algorithm is applied to 15 subjects of the MIMIC II Database and AHE and MAPDRs are consequently detected (MAP =60mmHg with endurance more than 30 minutes). As a result of this study, MAPDR is realized as a marker of cardiogenic shock. In that, for a sequence of MAPDRs as long as 20 minutes or more appeared in the MAP trend, there would exist an ensuing high peak with the duration of 3 to 4 minutes in the probability of shock diagram which is derived using the risk scoring model developed by Hasdai et al., 2000.

(Abstract Control Number: 183)