Abstract: A backup power supply includes at least one ultra capacitor to store energy. The backup power supply includes a multiphase boost converter to provide a relatively constant voltage level from the energy stored on the at least one ultra capacitor. A charging and discharging controller is used to monitor the status of a power supply and control the charging and discharging of the ultra capacitors.

Abstract: The present invention relates to a system and method for determining the impedance of an electrode at the electrode-body interface. The electrode-body impedance of one of the electrodes may be calculated using the voltage difference between that electrode and a plurality of other electrodes, and the voltage and impedance of an alternating current generator in communication with the electrodes.

Abstract: A backup power supply includes at least one ultra capacitor to store energy. The backup power supply includes a multiphase boost converter to provide a relatively constant voltage level from the energy stored on the at least one ultra capacitor. A charging and discharging controller is used to monitor the status of a power supply and control the charging and discharging of the ultra capacitors.

Abstract: The present invention relates to a system and method for determining the impedance of an electrode at the electrode-body interface. The electrode-body impedance of one of the electrodes may be calculated using the voltage difference between that electrode and a plurality of other electrodes, and the voltage and impedance of an alternating current generator in communication with the electrodes.

Abstract: A system and method for triggering an external device in response to an electrocardiogram signal. In one embodiment the method includes determining a peak in the electrocardiogram signal, determining if the electrocardiogram signal is rising or falling at the peak in the signal and triggering a device in response to the rising or falling peak. In one embodiment of the invention an external trigger signal is produced only a rising peak is detected. In one embodiment, the system includes a microprocessor, a peak detector and a trigger circuit. The trigger circuit outputs a trigger signal to an external device when signaled by the peak detector and not inhibited by a signal from the microprocessor.

Abstract: A device, system and method for a backup power supply are disclosed herein. The backup power supply may use at least one ultra capacitor to store a voltage. The backup power supply may also have a multiphase boost converter to provide a relatively constant voltage from the stored voltage and a constant changing power filter to regulate a current that is used to charge the ultra capacitor. A charging and discharging controller may be used to monitor the status of a power supply and control the charging and discharging of the ultra capacitors.

Abstract: Improved cardiocirculatory assistance is provided to a patient by detecting the onset of ventricular ejection in the cardiac cycle of the patient and selectively increasing intrathoracic pressure of the patient in relative phase with respect to the onset of ventricular ejection. Cardiocirculatory output may be monitored and the relative phase of the increase in intrathoracic pressure with respect to the onset of ventricular ejection adjusted to maximize cardiac output. The intrathoracic pressure is increased once every N cardiac cycles where N is a positive integer. The patient interface may include apparatus for supplying high frequency respiration pulses in synchronism with the cardiac cycle. Alternately, or in addition, the pulses may be used to inflate a bladder in contact with the thorax.

Abstract: An improved apparatus for non-invasive measurement of transcutaneous carbon dioxide pressure employs a skin engaging sensor including pH and reference electrodes and a temperature sensor. The temperature sensor produces an output signal voltage having a characteristic which can be the same as or the complement of the voltage-temperature characteristic of the deviation voltage component of the pH-reference electrode voltage attributable to temperature deviation effects on the sensor as well as on the skin. An error signal voltage produced at the output of the temperature sensor is combined with the voltage measured across the pH and reference electrodes to provide a corrected voltage having a magnitude indicative of transcutaneous carbon dioxide pressure at a predetermined reference temperature without need to heat the skin or electrode or otherwise control their temperatures.

Abstract: An apparatus and method for measuring and monitoring blood oxygen content and local perfusion factor. A transcutaneous gas measurement probe is heated by application of an electric current to a semi-conductor device housed therein. The heat developed in a semi-conductor device heats the probe to a constant temperature under the control of a temperature monitoring and regulating circuit and the amount of power applied to the semi-conductor device is measured by multiplying the current conducted through the semiconductor device by the voltage across it to provide a measurement of local perfusion factor. An alerting device is provided to signal when blood oxygen content and local perfusion factor are outside a predetermined acceptable range.

Abstract: Apparatus and a method for determining the onset of an interarterial blood pressure pulse and measuring the time delay preceding the onset from the corresponding electrical heartbeart triggering signal wherein the blood pressure pulse is converted to an electrical input signal which is split into two identical components, one being delayed in time, inverted and amplified after which it is added to the other. A timer measures the duration between the electrical heartbeat actuating signal and the point at which the sum of the blood pressure component signals reaches a peak and subtracts from that result the time delay applied to the one component to yield the electromechanical interval between the electrical heartbeat signal and onset of the blood pressure pulse.