Surgery: light – thermal – and electrical application – Light – thermal – and electrical application – Electrical therapeutic systems
Patent
1996-08-19
2000-05-02
Jaworski, Francis J.
Surgery: light, thermal, and electrical application
Light, thermal, and electrical application
Electrical therapeutic systems
600547, A61N 3900
Patent
active
060583258
ABSTRACT:
Impedance across a load, such as a pair of face-to-face electrodes and/or a patient's transthoracic and transmyocardial impedance, respectively, is modeled as a resistor in series with a capacitor, wherein the reactance component of the impedance equals 2 .pi.*frequency/capacitance. A reference square wave voltage is applied to the load in series with a selected load resistor, and a response voltage is measured across the load. Both the reference voltage and the response voltage are then used to estimate a transfer function between them. Equating this transfer function to a resistor-capacitor circuit model results in estimation of the actual resistance and capacitance components of the true impedance. Alternately, the impedance may be measured with a high current load, such as during a defibrillator discharge. In this case, the voltage input and outputs are sampled at a much faster rate for the resistance component estimation, with the capacitance initialization adapted for the specific type of defibrillator waveform input.
REFERENCES:
patent: 4782281 (1988-11-01), Williamson
patent: 5309917 (1994-05-01), Wong et al.
patent: 5454377 (1995-10-01), Dzwonczyk et al.
patent: 5529072 (1996-06-01), Sramek
patent: 5601612 (1997-02-01), Gliner et al.
patent: 5836977 (1998-11-01), Myers
G. V. Reklaitis, et al., "Functions of a Single Variable", Engineering Optimization --Methods and Applications, John Wiley and Sons, 1983, pp. 48-50.
Shubba Kadambe, et al., "The Dyadic Wavelet Transform Based QRS Detector", The Twenty-Sixth Asilomar Conference on Signals, Systems & Computers, Oct. 26-28, 1992, IEEE Computer Society Press, vol. 1 of 2, pp. 130-134.
Geddes, L.A., "Electrodes for Transchest and ICD Defibrillation and Multifunctional Electrodes", Defibrillation of the Heart -- ICSs, AEDs, and Manual, Mosby, 1994, Chapter 4, pp. 82-104.
Geddes, L.A., et al., "The Prediction of the Impedance of the Thorax to Defibrillating Current", Medical Instrumentation, vol. 10, No. 3, May-Jun. 1976, Assoc. for the Advancement of Medical Instrumentation, pp. 159-162.
L.A. Geddes, L.A., et al., "The Impedance of Electrodes Used for Ventricular Defibrillation", Medical Instrumentation, vol. 9, No. 4, Jul.-Aug. 1975, Assoc. for the Advancement of Medical Instrumentation, pp. 177-178.
Richard E. Kerber, M.D. et al., "Advance Prediction of Transthoracic Impedance in Human Defibrillation and Cardioversion: Importance of Impedance in Determining the Success of Low-energy Shocks", Therapy and Prevention -- Defibrillation, Cardiovascular Center, University of Iowa Hospital, Iowa City, IA, Circulation 70, No. 2, Aug. 1984, pp. 303-308.
Cardiotronics
Jaworski Francis J.
LandOfFree
Method and apparatus for high current electrode, transthoracic a does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for high current electrode, transthoracic a, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for high current electrode, transthoracic a will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1601452