Time-frequency Features for Impedance Cardiography Signals During Anesthesia Using Different Distribution Kernels

Time-frequency Features for Impedance Cardiography Signals During Anesthesia Using Different Distribution Kernels.

OBJECTIVE This works investigates the time-frequency content of impedance cardiography signals during a propofol-remifentanil anesthesia. MATERIALS AND METHODS In the last years, impedance cardiography (ICG) is a technique which has gained much attention. However, ICG signals need further investigation. Time-Frequency Distributions (TFDs) with 5 different kernels are used in order to analyze ...

Systolic time intervals and impedance cardiography.

Impedance Cardiography *

Objective: To evaluate the following: (1) the intramethod variability of impedance cardiography (ICG) cardiac output (CO) measurements via the latest generation monitor and thermodilution CO measurements (CO-TDs); (2) the intermethod comparison of ICG CO and CO-TD; and (3) comparisons of the intergeneration ICG CO equation to CO-TD, using the latest ICG CO equation, the ZMARC (CO-ICG), and the ...

Beat-to-beat evaluation of systolic time intervals during bicycle exercise using impedance cardiography.

In order to elucidate the beat-to-beat changes of the systolic time intervals (STI) during exercise, we proposed new techniques relating to an adaptive filter and detection algorithms for B- and X-points in the impedance cardiograph (ICG). Six male subjects underwent a ramp bicycle exercise up to maximum intensity during which an ECG, ICG and phonocardiogram (PCG) were continuously measured. Fo...

Improved Detection of Ventricular Ejection Time for Impedance Cardiography

Impedance cardiography is a noninvasive technique for monitoring stroke volume (SV), based on sensing variation in the thoracic impedance due to blood flow. In this technique, first derivative of impedance (dz/dt) is used to calculate two parameters: ventricular ejection time and (-dz/dt)max. Respiration and motion artifacts cause base line drift in the sensed impedance waveform, and this resul...