Abstract:
The presence of a cardiac pulse in a patient is determined by evaluating fluctuations in an electrical signal that represents a measurement of the patient's transthoracic impedance. Impedance signal data obtained from the patient is analyzed for a feature indicative of the presence of a cardiac pulse. Whether a cardiac pulse is present in the patient is determined based on the feature in the impedance signal data. Electrocardiogram (ECG) data may also be obtained in time coordination with the impedance signal data. Various applications for the pulse detection of the invention include detection of PEA and prompting PEA-specific therapy, prompting defibrillation therapy and/or CPR, and prompting rescue breathing depending on detection of respiration.
Abstract:
A method and apparatus for measuring changes in the concentration of a particular gas component of a breathing gas mixture after inhalation and exhalation by means of a degradable sensor (41). This is done by exposing, during inhalation, the sensor (41) to a breathing gas mixture of known concentration to produce an inhalation output corresponding to the measured concentration of the gas component in the inhalation. From the known concentration of the gas component in the breathing gas mixture and the measured concentration in the inhalation output, a degradation parameter is determined representing the instantaneous degradation condition of the sensor. The sensor (41) is exposed to the breathing gas mixture during exhalation output corresponding to the measured concentration of the gas component in the exhalation; the exhalation output of the sensor (41) is modified according to the determined degradation parameter; and the change in concentration is computed from the modified exhalation output and the measured inhalation output.
Abstract:
An endovascular implant or endograft (18) includes a tubular sleeve having integral inner and outer layers (20, 22). A pressure sensor (S1-3) is embedded between the two layers and is covered thereby. And, the sleeve is flexible at the pressure sensor to permit transfer of pressure through the sleeve for detection by the pressure sensor in use.
Abstract:
Endocardial pressure measurement devices, systems and methods for effective treatment of congestive heart failure and its underlying causes, in addition to other clinical applications. A representative device includes an implantable pressure measuring system including a pressure transducer (31) and a fluid filled catheter (34), the catheter having a proximal portion (34A) and a distal portion (34B). The proximal portion (34a) is connected to the pressure transducer (31) and the distal portion (34b) has an opening (36) with a barrier (26). The proximal portion (34a) is relatively crush-resistant and the distal portion (34b) is relatively flexible.
Abstract:
This invention is a glucose measuring device for determining the concentration of glucose in intravascular blood within a body part of a subject. The device includes at least one light source (12) having a wavelength of 650, 880, 940, or 1300 nm to illuminate the fluid. At least one receptor (14) associated with the light source for receiving light and generating a transmission signal representing the light transmitted is also provided. A support piece is included for supporting the light source associated with the respective receptor. The support piece is adapted to engage a body part of a subject. A method for determining the glucose concentration is also provided which calibrates a measuring device and sets the operating current for illuminating the light sources during operation of the device. Once a transmission signal is generated by receptors (14) receiving light via the light source and illuminated blood, and the high and low values from each of the signals are selected and stored in the device (20), the values are subtracted to obtain a single transmission value for each of the light sources. These calculated values are then compared to a database of target values, either using a neural network, or directly compared to determine the glucose concentration, which value is then displayed (28) on the device.
Abstract:
Apparatus and methods for non-invasively determining cardiac output using partial re-breathing techniques are disclosed in which the apparatus is constructed with an instantaneously adjustable deadspace (70) for accommodating differences in breathing capacities various patients. The apparatus (50) is constructed of inexpensive elements, including a single two-way valve (22) which renders the apparatus very simple to use and inexpensive so that the unit may be readily disposable. The method of the invention provides a novel means (46) of estimating cardiac output based on alveolar CO2 values rather than end-tidal CO2 values as previously practiced. A program for calculating cardiac output is also disclosed.
Abstract:
Apparatus for the diagnosis of a skin disease site (3) by visual fluorescence inspection comprising an excitation light source (1)for illuminating the disease site (3), a light guide (2) for transmitting the excitation light directly to the disease site to generate fluorescence light and viewing goggles (4) for processing the excitation light reflected and the fluorescence light emitted from the disease site to provide a fluorescence image of the disease site to a user. The fluorescence image is used to aid the medical assessment of skin conditions and the diagnosis of cutaneous diseases by supplementing the visual assessment of skin lesions made by the naked eye. The apparatus can be used in several modes of operation that permit the viewing of full color fluorescence images and enhanced two color images. The apparatus can also use image intensifying equipment (10) to amplify fluorescence light so that even very weak fluorescing objects can be seen. A method for acquiring and viewing the fluorescence images is also disclosed.
Abstract:
A light guide tube (15) which guides an infrared radiation from a measured object, a 1st infrared sensor (10) which detects the infrared radiation from the light guide tube (15), a temperature sensor (12) which generates a reference temperature signal, a reference cavity (17) which shows a temperature status approximately the same as the temperature status of the light guide tube (15) and is closed so as to prevent the incidence of an external infrared radiation, a 2nd infrared sensor (11) which detects an infrared radiation from the reference cavity (17), a temperature calculating means (13) which calculates the temperature of the object in accordance with the signals from the 1st infrared sensor (10), the 2nd infrared radiation sensor (11) and the temperature sensor (12) and a display (14) which displays the temperature in accordance with a signal from the temperature calculating means (13) are provided. The diameter of at least one of the light guide tube (15) and the reference cavity (17) is gradually reduced from the side of the 1st and 2nd infrared sensors (10 and 11) toward the light incidence opening of the light guide tube (15).
Abstract:
A method of wireless communication with a medical device, especially one implanted in the human body. A message input signal (S1, g4) undergoes angular modulation in a transmitter (2 - 8, 16 - 26) and reaches a receiver via a transmission channel (11-15,16 - 26). The transmitter produces angularly modulated pulses having a frequency spectrum and carrying information, in such a way that said pulses can be time-compressed in the transmitter by means of a filter (13) with a frequency dependent transit time, especially a dispersion filter (13,32, 33) so that pulses with reduced duration and higher amplitude can arise, and at least one part of the information that makes up the message is impressed after a further modulation or message technology coding process and is subsequently received and/or at least one part of the information that makes up the message is impressed in addition to the angular modulation.
Abstract:
A specimen collecting device (10) has an elongated foam member (15) that is circumscribed by a hollow tubular member (12) along a portion of its longitudinal axis. The hollow tubular member (12) has a cross-sectional area less than the uncompressed cross-sectional area of the foam member (15) so that the foam member (15) is compressed along the circumscribed portion.