161 results about "Blood oxygenation" patented technology

A method and an apparatus measure blood oxygenation in a subject. A first signal source applies a first input signal during a first time interval. A second signal source applies a second input signal during a second time interval. A detector detects a first parametric signal responsive to the first input signal passing through a portion of the subject having blood therein. The detector also detects a second parametric signal responsive to the second input signal passing through the portion of the subject. The detector generates a detector output signal responsive to the first and second parametric signals. A signal processor receives the detector output signal and demodulates the detector output signal by applying a first demodulation signal to a signal responsive to the detector output signal to generate a first output signal responsive to the first parametric signal. The signal processor applies a second demodulation signal to the signal responsive to the detector output signal to generate a second output signal responsive to the second parametric signal. The first demodulation signal and the second demodulation signal both include at least a first component having a first frequency and a first amplitude and a second component having a second frequency and a second amplitude. The second frequency is a harmonic of the first frequency. The second amplitude is related to the first amplitude to minimize crosstalk from the first parametric signal to the second output signal and to minimize crosstalk from the second parametric signal to the first output signal.

Methods and systems for long term monitoring of one or more physiological parameters such as respiration, heart rate, body temperature, electrical heart activity, blood oxygenation, blood flow velocity, blood pressure, intracranial pressure, the presence of emboli in the blood stream and electrical brain activity are provided. Data is acquired non-invasively using ambulatory data acquisition techniques.

A system for monitoring medical conditions including pressure ulcers, pressure-induced ischemia and related medical conditions comprises at least one sensor adapted to detect one or more patient characteristic including at least position, orientation, temperature, acceleration, moisture, resistance, stress, heart rate, respiration rate, and blood oxygenation, a host for processing the data received from the sensors together with historical patient data to develop an assessment of patient condition and suggested course of treatment. In some embodiments, the system can further include a support surface having one or more sensors incorporated therein either in addition to sensors affixed to the patient or as an alternative thereof. The support surface is, in some embodiments, capable of responding to commands from the host for assisting in implementing a course of action for patient treatment. The sensor can include bi-axial or tri-axial accelerometers, as well as resistive, inductive, capactive, magnetic and other sensing devices, depending on whether the sensor is located on the patient or the support surface, and for what purpose.

A monitoring device (20) and method (200) for monitoring the health of a user is disclosed herein. The monitoring device (20) is preferably a watch (25), an optical sensor (30) disposed on a band of the watch (25), a circuitry assembly (35) embedded within a main body of the watch (25), a display member (40) disposed on an exterior surface of the main of the watch, and a control component (43). The monitoring device (20) preferably displays the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and dynamic blood pressure. The watch (25) also displays the time of day on the display member (40).

A method and apparatus for non-invasively determining the blood oxygen saturation level within a subject's tissue is provided that utilizes a near infrared spectrophotometric (NIRS) sensor capable of transmitting a light signal into the tissue of a subject and sensing the light signal once it has passed through the transmitting a light signal into the subject's tissue, wherein the transmitted light signal includes a first wavelength, a second wavelength, and a third wavelength; (2) sensing a first intensity and a second intensity of the light signal, along the first, second, and third wavelengths after the light signal travels through the subject at a first and second predetermined distance; (3) determining an attenuation of the light signal for each of the first, second, and third wavelengths using the sensed first intensity and sensed second intensity of the first, second, and third wavelengths; (4) determining a difference in attenuation of the light signal between the first wavelength and the second wavelength, and between the first wavelength and the third wavelength; and (5) determining the blood oxygen saturation level within the subject's tissue using the difference in attenuation between the first wavelength and the second wavelength, and the difference in attenuation between the first wavelength and the third wavelength.

A non-invasive near infrared spectrophotometric monitoring transducer assembly includes a housing member, which is adhered directly on a patient's skin. The housing member contains a prism coupled to a flexible and lightweight single core optical light guide, which provides a means of transferring narrow spectral bandwidth light from multiple distant laser diodes of different wavelengths by use of a multi-fiber optic light combining assembly. Different wavelengths are needed to monitor the level of blood oxygenation in the patient. The assembly also contains a planar light guide mounted on the prism located in the housing member, which light guide contacts the patient's skin when the housing member is adhered to the patient's skin. The light guide controls the spacing between the prism and the patient's skin, and therefore controls the intensity of the area on the patient's skin which is illuminated by the laser light. The housing member contains a photodiode assembly, which detects the infrared light at a second location on the skin to determine light absorption. The photodiode assembly is preferably shielded from ambient electromagnetic interference (EMI) by an optically transparent EMI attenuating window. This rigid window placed over the photodiode also provides a planar interface between the assembly and the skin, improving optical coupling and stability as well as reducing the capacitive coupling between skin and the photodiode resulting in further EMI attenuation. The housing may be associated with a disposable sterile hydrogel coated adhesive envelope, or pad, which when applied to the patient's skin will adhere the housing to the patient's skin. The transducer assembly will thus be reusable, and skin-contacting part of the device, i.e., the envelope or pad can be discarded after a single use. The assembly also includes a laser safety interlock means, which is operable to turn off the laser light output in the event that the assembly accidentally becomes detached from the patient's skin.

A monitoring device (20) for monitoring the vital signs of a user is disclosed herein. The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and/or dynamic blood pressure. The article (25) is preferably a band worn on a user's wrist, arm or ankle.

A monitoring device (20) for monitoring the vital signs of a user is disclosed herein. The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35). The optical sensor (30) preferably comprises a photodetector (130) and a plurality of light emitting diodes (135). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and/or dynamic blood pressure.

Apparatus for monitoring a plurality of tissue viability parameters of a tissue layer element, in which two different illumination sources are used via a common illumination element in contact with the tissue. One illumination source is used for monitoring blood flow rate and optionally flavoprotein concentration, and collection fibers are provided to receive the appropriate radiation from the tissue. The other illuminating radiation is used for monitoring any one of and preferably all of NADH, blood volume and blood oxygenation state of the tissue element, and collection fibers are provided to receive the appropriate radiation from the tissue. In one embodiment, the wavelengths of the two illumination sources are similar, and common collection fibers for the two illuminating radiations are used. In another embodiment, the respective collection fibers are distanced from the illumination point at different distances correlated to the ratio of the first and second illuminating wavelengths.

The present invention is directed toward a system for monitoring a region of a person to determine a plurality of physiological characteristics, including blood oxygenation levels, blood gases, respiratory rates, and pulse rates. The monitored region includes at least a portion of a dermal layer extending over anywhere on the chin, including at least one of the subject's mandible, symphysis, mental protuberance, or incisive fossa. The system comprises a sensor having at least one light emitting source and at least one detector. Preferably, the sensor is positioned on the region being monitored and is secured to the region being monitored by a securing means. Optionally, the securing means comprises a strap that is adjustable and in physical communication with the housing. In one embodiment, the strap is attached to an apparatus and the apparatus is capable of being secured to a head of the subject. The apparatus can be attached to a helmet and used for at least one of a military, sporting, construction, security, policing, or firefighting application.

A system for monitoring medical conditions including pressure ulcers, pressure-induced ischemia and related medical conditions comprises at least one sensor adapted to detect one or more patient characteristic including at least position, orientation, temperature, acceleration, moisture, resistance, stress, heart rate, respiration rate, and blood oxygenation, a host for processing the data received from the sensors together with historical patient data to develop an assessment of patient condition and suggested course of treatment, including either suspending or adjusting turn schedule based on various types of patient movement. The sensor can include one or more of bi-axial or tri-axial accelerometers, magnetometers and altimeters as well as resistive, inductive, capacitive, magnetic and other sensing devices, depending on whether the sensor is located on the patient or the support surface, and for what purpose. In some embodiments, the sensor can be self-contained in that it can detect orientation and suggest repositioning independent of a host.

A near infrared spectrophotometric (NIRS) sensor assembly for non-invasive monitoring of blood oxygenation levels in a subject's body is provided that includes a pad, at least one light source, a near light detector, a far light detector, and a cover. The light source is operative to emit near infrared light signals of a plurality of different wavelengths. The near light detector is separated from the light source by a first distance that is great enough to position the first light detector outside of an optical shunt field extending out from the light source. The far light detector is substantially linearly aligned with the near light detector and light source, and is separated from the near light detector by a second distance, wherein the second distance is greater than the first distance.

Apparatus for detecting intracranial temperature and blood oxygenation includes a transducer having a working surface for placement against a patient's cranium. The transducer forms a microwave antenna having walls defining an aperture having a pair of opposite broader boundaries and a pair of opposite narrower boundaries at the working surface. The antenna is tuned to a frequency which produces a first output signal indicative of heat emanating from the cranium. An oxygen saturation sensor sharing that aperture includes a radiation emitter located at one of narrower boundaries which directs electromagnetic radiation across the aperture to a radiation detector at the other of the narrower boundaries and which produces a corresponding second output signal. A control unit includes a display and a processor for processing the signals to calculate an intracranial temperature and an oxygen saturation value for display by the control unit.

Apparatus for oxygenating and pumping blood includes a housing defining a blood flow path including, in series, a gas collection plenum, a pump space and a blood oxygenation element. A pump disposed in the pump space is configured to draw blood from the gas collection plenum and propel blood from the pump space through a heat exchanger and the blood oxygenation element. The heat exchanger includes a heat exchange plate and a coolant space.

A monitoring device (20) for monitoring the vital signs of a user is disclosed herein. The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35). The optical sensor (30) preferably comprises a photodetector (130) and a plurality of light emitting diodes (135). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; or distance traveled.

Apparatus and methods for pumping and oxygenating blood are provided that include a gas removal system. An integrated blood processing unit is provided in which a gas removal/blood filter, pump and blood oxygenation element are mounted within a common housing. The gas removal system includes a sensor mounted on the housing to sense the presence of gas, and a valve is operably coupled to the sensor to evacuate gas from the system when the sensor detects an accumulation of gas.

The application features methods, devices, and systems for measuring blood flow in a subject. The computer-implemented methods include receiving functional magnetic resonance imaging (fMRI) data that provides information on at least one of volume or oxygenation of blood at one or more locations in a body over a first predetermined length of time. The methods also include receiving near-infrared spectroscopic (NIRS) imaging or measurement data representing at least one of blood concentration or oxygenation at a first portion of the body over a second predetermined length of time. The methods further include deriving, from the fMRI data corresponding to a second portion of the body, a time varying data set representing changes in blood oxygenation or volume or both blood oxygenation and volume at the second portion over the first predetermined length of time and determining, by a computing device, a time delay and a value of a similarity metric corresponding to a part of the spectroscopic imaging data that most closely matches the time varying data set. The time delay represents a difference between a first time in which blood flows from a third portion in the body to the first portion and a second time in which blood flows to the second portion from the third portion. The value of the similarity metric represents an amount of blood at the second portion. An estimate of a characteristic of at least one of blood flow or blood volume in the second portion at a given time is determined based on the time delay and the value of the similarity metric.