# Cardiac Output Estimation from Arterial Blood Pressure Waveforms 1.0.0

(3,158 bytes)

```
function y = evco(fname,estID,winsize,clbnum)
% EVCO Evaluate CO estimation
% Y = EVCO(FNAME, ESTID, WINSIZE, CLBNUM) calibrates and evaluates CO
% estimation performance, using thermodilution CO as gold-standard.
%
% In: FNAME (string) file name -- e.g. fname='~/170.mat';
% ESTID (integer) choose CO estimation algorithm
% WINSIZE (integer) ABP window size (in seconds) to use
% CLBNUM (integer) choose calibration method:
% = 1 single k MMSE
% = 2 multi k causal MMSE
% = 3 single k 1st point
% = 4 multi k previous point
% = 5 not calib, but normalize near 1
% = other --- no calib
%
% Out: Y
% Col 1: enumerate CO number
% 2: time [min]
% 3: TCO [L/min]
% 4: estimated CO [L/min] - possibly uncalibrated
% 5: sigma of estimated CO [L/min] - possibly uncalibrated
% 6: sqi percent of good beats [mmHg]
% 7: Systolic BP [mmHg]
% 8: Diastolic BP [mmHg]
% 9: Pulse pressure [mmHg]
% 10: Mean pressure [mmHg]
% 11: heart rate [bpm]
% 12: noisiness (sqi thresh at -3)
% 13: Area under systole 0.3*sqrt(RR) method
% 14: Area under systole 1st min-slope method
%
% Example:
% y = evco('170',5,60,1);
%
% Written by James Sun (xinsun@mit.edu) on Jan 18, 2006.
% - v2.0 - 1/30/06 - add features (cols 7 thru 14) to output
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% get TCO, estimated CO data
load(fname,'t0','m2t');
% obtain TCO, sync TCO time with ABP time
t0_co = 24*60*(m2t.t0 - t0(1,1)); % minutes offset
r = [(t0_co+m2t.CO(:,1)) m2t.CO(:,2)];
% run bb CO estimate
[est_val,t_est,t_raw,F] = estimateCO(fname,estID,0);
x = [t_est*60 double(est_val)];
t_raw = t_raw*60;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% windowing --- obtain one-to-one estimates with tco
mu = zeros(size(r,1),1);
sigma = zeros(size(r,1),1);
sqi = zeros(size(r,1),1);
fea = zeros(size(r,1),8);
for i=1:size(r,1)
T = r(i,1)*60;
ind = find(x(:,1)<T & x(:,1)>T-winsize);
ind_raw = find(t_raw<T & t_raw>T-winsize);
if isempty(ind)
mu(i) = NaN;
sigma(i) = NaN;
sqi(i) = 0;
fea(i,:) = NaN;
else
mu(i) = mean(x(ind,2));
sigma(i) = std(x(ind,2));
sqi(i) = round(length(ind)/length(ind_raw) * 100);
fea(i,:) = mean(F(ind,[2 4 5 6 7 8 10 12]));
end
end
% heart rate
fea(:,5) = 60*125./fea(:,5);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% calibration
ind_nan = ~isnan(mu);
k = calib(r(ind_nan,2),mu(ind_nan),clbnum);
y = [(1:size(r,1))' r k.*mu k.*sigma sqi fea];
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% format output
%y(isnan(mu),:)=[];
```