41 results about "Thoracic Fluid" patented technology

A portable thoracic impedance monitor for monitoring thoracic fluid levels, an electrode array assembly having a single linear electrode array lead with first, second, third, and fourth electrodes arranged sequentially and axially along the linear electrode array lead, and a method of use of the thoracic impedance monitor. A measurement of the user's thoracic impedance is obtained by connecting the second electrode to the user's body at the junction of the clavicles, superior to the sternum, the third electrode to the user's body at the xyphiod-sternal junction, and the first and fourth electrodes to the user's body substantially along a centerline of the user's sternum respectively at a first pre-determined distance above the second electrode and a second predetermined distance below the third electrode, followed by initiating operation of the monitor.

A fluid status monitoring system for use in implantable cardiac stimulation or monitoring devices is provided for monitoring changes in thoracic fluid content. A fluid status monitor includes excitation pulse generating and control circuitry, and voltage and current measurement and control circuitry for performing a series of cardiac-gated, intra-thoracic impedance measurements. The cardiac-gated measurements are filtered or time-averaged to provide a fluid status impedance value, with respiratory noise removed. Based on comparative analysis of the fluid status impedance value, a clinically relevant trend in fluid status may be tentatively diagnosed and a fluid status response provided. Cross-check intra-thoracic impedance measurements performed using the same or a different excitation pathway and a different measurement pathway than the primary intra-thoracic impedance measurement configuration may be used to verify a tentative diagnosis.

Various techniques are provided for calibrating and estimating left atrial pressure (LAP) using an implantable medical device, based on impedance, admittance or conductance parameters measured within a patient. In one example, default conversion factors are exploited for converting the measured parameters to estimates of LAP. The default conversion factors are derived from populations of patients. In another example, a correlation between individual conversion factors is exploited to allow for more efficient calibration. In yet another example, differences in thoracic fluid states are exploited during calibration. In still yet another example, a multiple stage calibration procedure is described, wherein both invasive and noninvasive calibration techniques are exploited. In a still further example, a therapy control procedure is provided, which exploits day time and night time impedance/admittance measurements.

This patent document discusses, among other things, systems, devices, and methods for predicting an occurrence of impending thoracic fluid accumulation and in one example, invoking a responsive therapy, such as to prevent or minimize the consequences of the impending thoracic fluid accumulation. One example of the present systems, devices, and methods senses or receives at least one parameter that is statistically associated with impending thoracic fluid accumulation from a subject. Using such parameter(s), a probability of impending thoracic fluid accumulation is estimated. A list of parameters determines which values are recurrently sensed or received at various desired time intervals. Another example of the present systems, devices, and methods weights the sensed or received parameter value(s) to compute the probability estimate of impending thoracic fluid accumulation. A responsive preventive thoracic fluid accumulation therapy or other therapy is selected and activated using the probability estimate of impending thoracic fluid accumulation.

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.

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.

Techniques are provided for monitoring thoracic fluid levels based on thoracic impedance (Z_T) and cardiogenic impedance (Z_C). In one example, the implantable device tracks the maximum time rate of change in cardiogenic impedance (i.e. max(dZ_C/dt)) to detect trends toward hypervolemic or hypovolemic states within the patient based on changes in heart contractility. The detection of these trends in combination with trends in thoracic impedance allows for a determination of whether the thoracic cavity of the patient is generally “too wet” or “too dry,” and thus allows for the titration of diuretics to avoid such extremes. In particular, a decrease in thoracic impedance (Z_T) in combination with a decrease in max (dZ_C/dt) is indicative of the thorax being “too wet” (i.e. a fluid overload). Conversely, an increase in thoracic impedance (Z_T) in combination with a decrease in max (dZ_C/dt) is indicative of the thorax being “too dry” (i.e. a fluid underload).

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.

This document describes ways in which to alter physiological signals to address corrupt, noisy, or otherwise faulty data. By so doing, accuracy and robustness in sensing and assessing a patient's cardiovascular health can be improved. These improved assessments permit better measures of health, such as relevant hemodynamics understood by heart rates, heart rate variability, cardiac arrhythmias, blood pressures, pulse-wave velocities, arterial stiffness, cardiac valve timing, thoracic fluids, ballistocardiogram force, photo-plethysmograms, blood oxygenation, and pressure-volume loops.

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.

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.

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.

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.

The invention discloses a thin-catheter closed type chest fluid drainage device, which comprises a drainage thin catheter, a fluid storage unit, a negative pressure generation unit, a catheter switchand a fixing unit, wherein two ends of the drainage thin catheter are both opening ends; the fluid storage unit is in communication installation on one end of the drainage thin catheter; the negativepressure generation unit and the fluid storage unit are in communication connection; the catheter switch and the fixing unit are both sheathed out of the drainage thin catheter; in addition, the catheter switch is positioned between the fixing unit and the fluid storage unit; and one end, which is far away from the fluid storage unit, of the drainage thin catheter is a free end. By use of the thin-catheter closed type chest fluid drainage device, negative pressure suction is used so as to be favorable for successfully draining and discharging hydrops in the chest of a patient, a drainage effect is good, a treatment effect is effectively guaranteed, the drainage thin catheter can be prevented from falling from the chest of the patient, the life safety of the patient is effectively guaranteed, a prepared protection layer can avoid a situation that a great quantity of bacteria is bred on the inner surface and the outer surface of a fluid storage bottle to generate peculiar smells, and a use sanitary condition is good.

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.