Abstract: An apparatus and method for determining stroke volume by bioimpedance from a person that includes two or more spaced apart alternating current flow electrodes positionable on a person's forearm, two or more spaced apart voltage sensing electrodes positionable on the person's forearm and between the alternating current flow electrodes, an alternating current source providing an alternating current to the current flow electrodes, a voltmeter configured to generate a voltage signal from a voltage sensed by the voltage sensing electrodes, and a processing unit configured to determine a stroke volume (SV) using the voltage signal and at least one of two equations that include, among other terms, the person's weight, a peak time rate of change of a transradioulnar impedance pulse variation (dZ/dtmax), a transradioulnar quasi-static base impedance (Z0), a systolic flow time (TSF), and a volume conductor (Vc).

Abstract: Provided herein are methods and apparatus for stroke volume determination by bioimpedance from a patient's upper arm, or brachium, or a patient's thorax, utilizing pulsations of the arteries contained therein. The apparatus includes two or more spaced apart alternating current flow electrodes positioned on the patient's arm or thorax and two or more spaced apart voltage sensing electrodes positioned on the patient's arm or thorax and in-between alternating current flow electrodes. The system and method utilizes the mean value of the second time-derivative of the cardiogenically induced impedance variation of the patient using the measured voltage from the voltage sensors in calculating the stroke volume of the patient.

Abstract: Provided herein are methods and apparatus for stroke volume determination by bioimpedance from a patient's upper arm, or brachium, or a patient's thorax, utilizing pulsations of the arteries contained therein. The apparatus includes two or more spaced apart alternating current flow electrodes positioned on the patient's arm or thorax and two or more spaced apart voltage sensing electrodes positioned on the patient's arm or thorax and in-between alternating current flow electrodes. The system and method utilizes voltage sensed by the voltage sensing electrodes to calculate a cardiogenically induced impedance variation value of the patient, and to determine a stroke volume of the patient by multiplying the cardiogenically induced impedance variation value by a volume conductor VC and by a left ventricular ejection time TLVE.