Apparatus for calculating cardiac output

G - Physics – 01 – F

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

73/168, 354/31,

G01F 1/72 (2006.01) A61B 5/0275 (2006.01) G01F 1/704 (2006.01)

Patent

CA 1139883

ABSTRACT OF THE DISCLOSURE The invention provides apparatus for measuring the flow rate of liquid being circulated in a closed system by a pump using a bolus of indicator injected suddenly into the system upstream of the pump and a sampling station downstream of the pump. The apparatus includes signal means for location at the sampling station and adapted to provide an electrical signal proportional to the concentration of the indicator passing said station, the electrical signal having an in- creasing portion followed by a decaying exponential portion and a distorted portion caused by recirculation of the in- dicator. A signal analyzer is coupled to said signal means to receive said electrical signal and is adapted to provide a continuous output during the whole of said electrical sig- nal corresponding to said increasing portion and said decaying exponential portion and including an extrapolated exponential portion replacing said distorted portion of the signal. The signal analyzer includes means to automatically zero said signal on a time base and a curve generator for re- ceiving said signal from the zeroing means. The curve generator includes a capacitor which is charged by said signal while the signal is increasing and the curve genera- tor is adapted to continuously compare the charge on said capacitor with said signal and to permit said capacitor to discharge exponentionally after said signal has reached a peak, at a rate matched to the decay rate of the electrical signal, said discharge rate continuously following the sig- nal exponential decay rate. The signal analyzer also in- cludes trigger means coupled to the curve generator and responsive to the charge on the capacitor, said trigger means being adapted to isolate the curve generator from said electrical signal when said charge on said capacitor has fallen to a predetermined level corresponding to a time during said exponential portion of said electrical signal and in advance of said distorted portion, whereby the signal analyzer output thereafter decays exponentially without interference from said distorted portion of the electrical signal. The apparatus also includes integrator means receiving said continuous signal analyzer output and adapted to integrate said output and provide a reading of the flow rate of the liquid.

308534

LandOfFree

Say what you really think

Search LandOfFree.com for Canadian inventors and patents. Rate them and share your experience with other people.

Rating

Apparatus for calculating cardiac output does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for calculating cardiac output, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for calculating cardiac output will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFCA-PAI-O-475646

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.