Abstract: The invention provides a neck-worn sensor (referred to herein as the ‘necklace’) that is a single, body-worn system that measures the following parameters from an ambulatory patient: heart rate, pulse rate, pulse oximetry, respiratory rate, temperature, thoracic fluid levels, stroke volume, cardiac output, and a parameter sensitive to blood pressure called pulse transit time. From stroke volume, a first algorithm employing a linear model can estimate the patient's pulse pressure. And from pulse pressure and pulse transit time, a second algorithm, also employing a linear algorithm, can estimate systolic blood pressure and diastolic blood pressure. Thus, the necklace can measure all five vital signs along with hemodynamic parameters. It also includes a motion-detecting accelerometer, from which it can determine motion-related parameters such as posture, degree of motion, activity level, respiratory-induced heaving of the chest, and falls.

Abstract: The invention provides a neck-worn sensor that is a single, body-worn system that measures the following parameters from an ambulatory patient: heart rate, pulse rate, pulse oximetry, respiratory rate, temperature, thoracic fluid levels, stroke volume, cardiac output, and a parameter sensitive to blood pressure called pulse transit time. From stroke volume, a first algorithm employing a linear model can estimate the patient's pulse pressure. And from pulse pressure and pulse transit time, a second algorithm, also employing a linear algorithm, can estimate systolic blood pressure and diastolic blood pressure. Thus, the sensor can measure all five vital signs along with hemodynamic parameters. It also includes a motion-detecting accelerometer, from which it can determine motion-related parameters such as posture, degree of motion, activity level, respiratory-induced heaving of the chest, and falls.

Abstract: The invention provides a system for monitoring a patient featuring a wearable mask coupled to a positive airway pressure machine that delivers a flow of gas at positive pressures, through the mask, and to an airway of the patient. Attached to the mask is an electronics control unit featuring a printed circuit board, a microprocessor, a wireless transmitter, and a battery. The electronics control unit has a weight less than 30 grams and is enclosed by an enclosure of having a volume of less than 180 cm2. A plurality of sensors electrically connect to the electronics control unit.

Abstract: A system for measuring a time-dependent impedance waveform from a patient, and calculating a parameter from this waveform. A wearable mask is coupled to a positive airway pressure machine to deliver a flow of gas to the patient. An impedance sensor attached to the wearable mask measures the IPG and/or BR waveform. The sensor features a first drive electrode that injects a first electrical current into the region, and a first sense electrode that measures an electrical signal related to the first electrical current and blood flow in the region. A processing system runs computer code configured to: 1) receive a digital representation of the time-dependent impedance waveform; and 2) process the digital representation, or a signal calculated therefrom, to determine the parameter.

Abstract: The invention provides a wearable mask for monitoring a blood pressure value and providing a flow of gas at a positive pressure to the patient. The mask includes a first sensor, configured to measure a time-dependent optical waveform from a first region underneath a first portion of the wearable mask, with the time-dependent optical waveform including a first pulse. A second sensor measures a time-dependent impedance waveform from a second region proximal to the mask, with the time-dependent impedance waveform including a second pulse. A microprocessor attaches to the wearable mask and is configured to: 1) receive digital representations of both the first and second pulses; 2) process the digital representations to determine a time difference between the first and second pulses, or a parameter calculated therefrom; and 3) process the time difference between the first and second pulses, or the parameter calculated therefrom, to determine the blood pressure value.

Abstract: The invention provides a system for automatically measuring an Activated Clotting Time value and other parameters from a sample of blood.

Abstract: The invention provides a system for measuring an Activated Clotting Time (ACT) value from a sample of blood. The system features a syringe component that encloses the sample of blood. Disposed within the syringe component are set of electrodes (composed, e.g., of metal pads or rings) that contact the sample of blood. An electronics module connected to the syringe component features an electrical impedance system that electrically connects to the set of electrodes and measures an impedance value indicating an electrical impedance of the sample of blood. A processing system receives the impedance value from the electronics module and: i) process it with a first algorithm to determine a viscosity value of the sample of blood; and ii) process the viscosity value with a second algorithm to determine the ACT value.

Abstract: The invention provides a neck-worn sensor that is a single, body-worn system that measures the following parameters from an ambulatory patient: heart rate, pulse rate, pulse oximetry, respiratory rate, temperature, thoracic fluid levels, stroke volume, cardiac output, and a parameter sensitive to blood pressure called pulse transit time. From stroke volume, a first algorithm employing a linear model can estimate the patient's pulse pressure. And from pulse pressure and pulse transit time, a second algorithm, also employing a linear algorithm, can estimate systolic blood pressure and diastolic blood pressure. Thus, the sensor can measure all five vital signs along with hemodynamic parameters. It also includes a motion-detecting accelerometer, from which it can determine motion-related parameters such as posture, degree of motion, activity level, respiratory-induced heaving of the chest, and falls.

Abstract: The invention provides a multi-sensor system that uses an algorithm based on adaptive filtering to monitor a patient's respiratory rate. The system features a first sensor selected from the following group: i) an impedance pneumography sensor featuring at least two electrodes and a processing circuit configured to measure an impedance pneumography signal; ii) an ECG sensor featuring at least two electrodes and an ECG processing circuit configured to measure an ECG signal; and iii) a PPG sensor featuring a light source, photodetector, and PPG processing circuit configured to measure a PPG signal. Each of these sensors measures a time-dependent signal which is sensitive to respiratory rate and, during operation, is processed to determine an initial respiratory rate value. An adaptive digital filter is determined from the initial respiratory rate. The system features a second sensor (e.g.

Abstract: The invention provides a body-worn system that continuously measures pulse oximetry and blood pressure, along with motion, posture, and activity level, from an ambulatory patient. The system features an oximetry probe that comfortably clips to the base of the patient's thumb, thereby freeing up their fingers for conventional activities in a hospital, such as reading and eating. The probe secures to the thumb and measures time-dependent signals corresponding to LEDs operating near 660 and 905 nm. Analog versions of these signals pass through a low-profile cable to a wrist-worn transceiver that encloses a processing unit. Also within the wrist-worn transceiver is an accelerometer, a wireless system that sends information through a network to a remote receiver, e.g. a computer located in a central nursing station.

Abstract: A system for monitoring a patient includes a first drive electrode configured to be in contact with the patient. The first drive electrode is configured to receive a first electrical current and inject it into the patient. The system also includes a first sense electrode configured to be in contact with the patient. The first sense electrode is configured to sense a first bio-electric signal from the patient. The first bio-electric signal is modified by the first electrical current. The system also includes an impedance circuit connected to the first drive electrode and the first sense electrode. The impedance circuit is configured to measure a bio-impedance or bio-reactance waveform in response to the first bio-electric signal. The system also includes a physiological sensor connected to the first drive electrode and the first sense electrode. The physiological sensor is configured to measure an electrocardiogram waveform based upon the first bio-electric signal.

Abstract: The invention provides a system and method for measuring vital signs and motion from a patient. The system features: (i) first and second sensors configured to independently generate time-dependent waveforms indicative of one or more contractile properties of the patient's heart; and (ii) at least three motion-detecting sensors positioned on the forearm, upper arm, and a body location other than the forearm or upper arm of the patient. Each motion-detecting sensor generates at least one time-dependent motion waveform indicative of motion of the location on the patient's body to which it is affixed.

Abstract: A handheld device measures all vital signs and some hemodynamic parameters from the human body and transmits measured information wirelessly to a web-based system, where the information can be analyzed by a clinician to help diagnose a patient. The system utilizes our discovery that bio-impedance signals used to determine vital signs and hemodynamic parameters can be measured over a conduction pathway extending from the patient's wrist to a location on their thoracic cavity, e.g. their chest or navel. The device's form factor can include re-usable electrode materials to reduce costs. Measurements made by the handheld device, which use the belly button as a ‘fiducial’ marker, facilitate consistent, daily measurements, thereby reducing positioning errors that reduce accuracy of standard impedance measurements. In this and other ways, the handheld device provides an effective tool for characterizing patients with chronic diseases, such as heart failure, renal disease, and hypertension.

Abstract: The invention provides a neck-worn sensor (referred to herein as the ‘necklace’) that is a single, body-worn system that measures the following parameters from an ambulatory patient: heart rate, pulse rate, pulse oximetry, respiratory rate, temperature, thoracic fluid levels, stroke volume, cardiac output, and a parameter sensitive to blood pressure called pulse transit time. From stroke volume, a first algorithm employing a linear model can estimate the patient's pulse pressure. And from pulse pressure and pulse transit time, a second algorithm, also employing a linear algorithm, can estimate systolic blood pressure and diastolic blood pressure. Thus, the necklace can measure all five vital signs along with hemodynamic parameters. It also includes a motion-detecting accelerometer, from which it can determine motion-related parameters such as posture, degree of motion, activity level, respiratory-induced heaving of the chest, and falls.

Abstract: A system and method for measuring vital signs and motion from a patient comprising a plurality of sensors, each comprising a processor and analog-to-digital converter configured to generate the physiologic data waveform(s) from the sensor as synchronized, separately resolvable digital data comprising a header indicating the sensor from which the digital data originates, and to transmit the physiologic data waveform(s) to a processing system via a cable comprising a terminal connector that reversibly mates with one of a plurality functionally equivalent of connectors to operably connect the sensor to the processing system. The processing system receive sthe physiologic data waveforms and determines therefrom one or more vital signs for the individual, which are transmitted to a remote vital sign monitor.

Abstract: The invention provides a neck-worn sensor (referred to herein as the ‘necklace’) that is a single, body-worn system that measures the following parameters from an ambulatory patient: heart rate, pulse rate, pulse oximetry, respiratory rate, temperature, thoracic fluid levels, stroke volume, cardiac output, and a parameter sensitive to blood pressure called pulse transit time. From stroke volume, a first algorithm employing a linear model can estimate the patient's pulse pressure. And from pulse pressure and pulse transit time, a second algorithm, also employing a linear algorithm, can estimate systolic blood pressure and diastolic blood pressure. Thus, the necklace can measure all five vital signs along with hemodynamic parameters. It also includes a motion-detecting accelerometer, from which it can determine motion-related parameters such as posture, degree of motion, activity level, respiratory-induced heaving of the chest, and falls.

Abstract: The invention provides a sensor for measuring both impedance and ECG waveforms that is configured to be worn around a patient's neck. The sensor features 1) an ECG system that includes an analog ECG circuit, in electrical contact with at least two ECG electrodes, that generates an analog ECG waveform; and 2) an impedance system that includes an analog impedance circuit, in electrical contact with at least two (and typically four) impedance electrodes, that generates an analog impedance waveform. Also included in the neck-worn system are a digital processing system featuring a microprocessor, and an analog-to-digital converter. During a measurement, the digital processing system receives and processes the analog ECG and impedance waveforms to measure physiological information from the patient. Finally, a cable that drapes around the patient's neck connects the ECG system, impedance system, and digital processing system.

Abstract: The invention provides a sensor for measuring both impedance and ECG waveforms that is configured to be worn around a patient's neck. The sensor features 1) an ECG system that includes an analog ECG circuit, in electrical contact with at least two ECG electrodes, that generates an analog ECG waveform; and 2) an impedance system that includes an analog impedance circuit, in electrical contact with at least two (and typically four) impedance electrodes, that generates an analog impedance waveform. Also included in the neck-worn system are a digital processing system featuring a microprocessor, and an analog-to-digital converter. During a measurement, the digital processing system receives and processes the analog ECG and impedance waveforms to measure physiological information from the patient. Finally, a cable that drapes around the patient's neck connects the ECG system, impedance system, and digital processing system.

Abstract: The invention provides a system for characterizing fluids in a tissue located in a portion of a patient. The system features an impedance system that includes a current-injecting electrode that injects an electrical current into the portion of the patient and a signal-measuring electrode that measures an impedance signal affected by the injected electrical current and an amount of the fluids. At least one of the electrodes includes an alignment feature that, during use, is aligned on the portion using a marking on the portion. The system also includes a processing system that receives the impedance signal from the impedance system or a signal determined from it. It then processes the signal to determine a parameter related to the degree of fluids in the tissue. The marking, for example, can be a permanent or semi-permanent marking, such as a tattoo.

Abstract: The invention provides a sensor for measuring both impedance and ECG waveforms that is configured to be worn around a patient's neck. The sensor features 1) an ECG system that includes an analog ECG circuit, in electrical contact with at least two ECG electrodes, that generates an analog ECG waveform; and 2) an impedance system that includes an analog impedance circuit, in electrical contact with at least two (and typically four) impedance electrodes, that generates an analog impedance waveform. Also included in the neck-worn system are a digital processing system featuring a microprocessor, and an analog-to-digital converter. During a measurement, the digital processing system receives and processes the analog ECG and impedance waveforms to measure physiological information from the patient. Finally, a cable that drapes around the patient's neck connects the ECG system, impedance system, and digital processing system.