Patent ID: 6821254
Filing Date: 2004-11-23
Classification: A61B

Abstract:
Apparatus for evaluating the condition of a patient who has symptoms of cardiopulmonary arrest comprising:a pair of electrodes for application to the chest of the patient: an electricity source for applying current between said electrodes to pass through the chest of the patient; a circuit which is coupled to said electrodes and which has an output that carries signals representing changes in impedance encountered by said current that represent cardiopulmonary activity of the patient; an analyzing circuit with an input that receives said signal representing the cardiopulmonary activity of the patient, and which determines the average frequency of those signals representing heartbeat rate and those signals representing breathing rate; wherein said analyzing circuit indicates cardiac arrest when the average frequency of those signals representing heartbeat rate is below a predetermined rate which is about 20 beats per minutes and the average frequency of those signals representing respiratory rate is below a predetermined rate which is about 4 breaths per minute.