Blood pressure project problem

[vqam]

hello,Sir,

hope u r fine.....we are final year students of biomedical engineering currently

working on project (Vital Signs Monitoring using LabVIEW). we are measuring 4

parameters i.e temperature, pulse oximeter, heart rate and blood pressure. we are

using DAQ card (PXI-6229) for interfacing hardware with LABVIEW.

we have to ask certain questions related to our project....

Currently working on Blood Pressure:

We are using MPX5050Dp pressure sensor, DC motor and valve. We are doing the

programming of blood pressure...we've done the programming of both motor and valve

control...and have also acquire pressure sensor voltage and have convert it into

mmHg.(also got bp graph)...

Sampling frequency =10kHz

Sampling rate =10Khz

And apply low pas filter and then band pas filter.

= low pass filter = 20hz order 6th order butterworth

= bandpass filter= 0.5-20hz order 6 butterworth

we are getting right graph but we are still unable to find mean arterial pressure

(map) and sytolic diastolic pressures.

from band pass filter graph we want to acquire the largest amplitude peak (which is

map)...

we tried different vi to got the largest amplitude but we are failed ....

tried

• max min array vi

• analog max min waveform vi

• amplitude and level vi( peak to peak)

• Power spectrum and FFT vi for max peak detection

• Peak detector

and also apply many program but …

from all these vi and program we've got amplitude of all peaks in the graph( which

we did not want)...we want only one largest amplitude..

we have generated array in which same value comes in each index. but we want to store all positive peaks .. and then retrieve maximum value from that array to find mean arterial pressure..suggest any way to generate different values at a time

we need ur help ..plz give some suggestions

[asbo]

You should post some sample data that you're trying to analysis as well as the code you're using. Otherwise, any advice is going to be shooting in the dark.

[Tim_S]

I second asbo's statement with the comment that the unfiltered data may be required; you're sampling at 10kHz, but filtering out everything above 20Hz quite harshly.

[vqam]

hello,,

in the output file, the above graph is the graph which we have obtained through bandpass filter. It is the oscillation graph from which we can find our mean arterial pressure.....For mean arterial pressure we want to find a single maximum peak which is coming near amplitude equals to 2 when the graph is increasing . we want to store that data in a 2d array so that we can compare the voltage level and its corresponding pressure retrieve

below one is the graph from Low pass filter....... can u suggest any way if we can find systolic and diastolic pressure from this graph?

need your suggestions

thankyou

.

[Skamronn]

Have you solved your problems? Otherwise, the normal method of obtaining sys/dia pressure is to detect the start and stop of oscillations in the pressure signal. And doing a max on the peak detector result should take care of the MAP. MAP can also be calculated from the sys/dia pressures.