摘要:
A method and apparatus for providing congestive heart failure therapy status. An electronic device, preferably a cardiac rhythm management device, capable of measuring transthoracic impedance and for sensing a level of physical activity is implanted in a patient. The transthoracic impedance signal is processed to obtain an estimate of the subject's minute ventilation, respiratory rate and tidal volume. From accelerometer measured activity, an estimate is obtained of oxygen uptake and carbon dioxide production. Ratios of tidal volume to respiratory rate, tidal volume to inspiratory time, minute ventilation to carbon dioxide production and oxygen uptake to heart rate are meaningftil status indicators for assessing the efficacy of particular therapy regimens to CHF patients.
摘要:
An implantable electronic circuit for monitoring a patient's aerobic capacity includes an accelerometer for detecting the onset and termination of a period of exercise and a means for measuring the patient's minute volume. By computing the time interval from the cessation of exercise to the point where the patient's minute volume reaches a predetermined value at or near an at-rest value thereof, a measure of aerobic capacity relating to a patient's physical fitness can be determined.
摘要:
An implantable cardiac rhythm management device includes an accelerometer along with apparatus for processing the analog signal output from the accelerometer for deriving therefrom the time of occurrence of a selected heart sound in relation to a previously occurring ventricular depolarization event. The thus-derived heart sound information can be used to establish a hemodynamic upper rate limit for a rate adaptive pacemaker.
摘要:
A motor vehicle antenna system is disclosed for receiving electromagnetically radiated signals in the FM radio broadcast frequency range. The antenna system includes a magnetic current receiving, conformal, substantially rectangular truncated slot antenna. The slot antenna is defined in part by a substantially horizontal portion of a conductive periphery of a window opening of the motor vehicle. The slot antenna is further defined in part by a conductive trace integral with a glazing panel mounted in the window opening. The conductive trace extends horizontally a distance equal to one-half a wavelength in the FM broadcast frequency band. The ends of the trace are effectively connected to the conductive periphery of the window opening. An electrical lead is provided for carrying signals from the slot antenna to a radio receiver, having a first conductor connected to the conductive window periphery and a second conductor coupled to the slot antenna, such as by a network feed structure integral with the windshield, optionally forming an electrical junction with the trace. The side points of the trace are effectively connected to the conductive periphery, e.g., by direct physical connection using an electrical lead, or by providing vertically-extending end traces parallel and proximate to opposite vertical portions of the electrically conductive periphery of the window opening.
摘要:
An automotive antenna system for receiving FM broadcast band radio signals includes a conformal antenna and a glazing panel having an electrically conductive coating. A conductive trace integrated with a front windshield panel, for example, forms an active slot antenna which is connected by a coaxial cable to the automobile's FM radio receiver. A transparent conductive layer is applied over a substantial portion of the rear window opening which is typically dimensioned such that it would otherwise be resonant within the FM broadcast band and parasitically coupled to the active antenna, which would cause the active antenna to have an undesirable directional pattern. The transparent layer has a sufficiently high conductivity and is applied over a sufficiently large portion of the resonant window opening to substantially reduce or eliminate resonances within the FM broadcast band.
摘要:
A disposable, integrated extracorporeal blood circuit employed during cardiopulmonary bypass surgery performs gas exchange, heat transfer, and microemboli filtering functions in a way as to conserve volume, to reduce setup and change out times, to eliminate a venous blood reservoir, and to substantially reduce blood-air interface. Blood from the patient or prime solution is routed through an air removal device that is equipped with air sensors for detection of air. An active air removal controller removes detected air from blood in the air removal device. A disposable circuit support module is used to mount the components of the disposable, integrated extracorporeal blood circuit in close proximity and in a desirable spatial relationship to optimize priming and use of the disposable, integrated extracorporeal blood circuit. A reusable circuit holder supports the disposable circuit support module in relation to a prime solution source, the active air removal controller and other components.
摘要:
A heat exchanger for medical applications is disclosed. The heat exchanger is characterized in that it is configured to provide a high heat transfer efficiency while minimizing the possibility of formation gaseous emboli and maximizing the ability to entrap and remove any such emboli which form or are introduced into the device. The heat exchanger is particularly well-suited for use in connection with cardioplegia apparatus.
摘要:
A vehicular radio reception antenna is concealed within a body trim piece such as a spoiler or a luggage rack. A supporting body panel is utilized as a ground plane and a conductive loop is concealed within the trim piece. A transmission line connects two opposite sides of the resulting slot. Capacitors are used to connect the conducting loop to the sheet metal ground plane in order to form a dual slot/monopole antenna for receiving both FM and AM signals.