The present invention relates to a device, system and method providing quantitative support for detection of return of spontaneous circulation during cardiopulmonary resuscitation. A photoplethysmography measurement is used to trigger a blood pressure measurement for assessing return of spontaneous circulation and hence for guiding a user through CPR. The present invention may prevent futile interruptions during compressions as well as re-arrest of the heart due to unnecessary compressions.

The present disclosure relates to a device, method and system for calculating, estimating, or monitoring the physiological parameters of a subject. At least one processor, when executing instructions, may perform one or more of the following operations. A first signal representing a pulse wave relating to heart activity of a subject may be received. A plurality of second signals representing time-varying information on the pulse wave may be received. A blood oxygen level of the subject based on the plurality of second signals may be determined. A first feature in the first signal may be identified. A second feature in one of the plurality of second signals may be identified. A pulse transit time based on a difference between the first feature and the second feature may be computed. A blood pressure of the subject may be calculated based on the pulse transit time.

A method is directed to continuously, non-invasively, and directly measuring blood pressure, and includes providing a calibrated measurement device having a blood-flow control balloon and a sensor array. The method further includes placing the sensor array in a non-invasive manner over the surface of a patch of skin connected to an artery by adjoining soft tissues and inflating the blood-flow control balloon with a controlled amount of pressure. In response to the inflating of the blood-flow control balloon, changes in the artery geometry and forces are detected, via the sensor array, during a heartbeat cycle. The changes correspond to spatio-temporal signals from the artery or in the adjoining soft tissues. The spatio-temporal signals are measured and processed, via a controller, to determine blood-pressure parameters.

A blood pressure measurement apparatus includes a pressure controller that controls an internal pressure of a cuff, an oscillation acquiring section that acquires an oscillation corresponding to a pressure vibration, a pulse wave signal acquiring section that acquires a pulse wave signal of the subject from a probe, a processor, and a memory that stores instructions executable by the processor. In the apparatus, when the instructions are executed by the processor, the apparatus causes the pressure controller to inflate the internal pressure, determines whether a first condition is satisfied or not, determines whether a second condition is satisfied or not, and if the first condition and the second condition are satisfied, determines a mean blood pressure of the subject based on the internal pressure.

The invention comprises an apparatus and a method for operating a cardiac assist pump, comprising the steps of: (1) providing a cardiac monitor comprising: a cardiac output sensor including an activity sensor and at least two of: a pulse oximeter; an electrocardiogram meter; and a blood pressure monitor; (2) receiving time-varying cardiovascular input data, from the cardiac output sensor, related to a transient hemodynamic state of a cardiovascular system; (3) receiving and operating on time-varying activity input data, from the activity sensor, to generate cardiovascular state information; (4) sensing activity with the activity sensor to generate a target cardiovascular state; (5) repeating both the steps of receiving and operating to update the transient cardiovascular state information and the step of sensing to update the target cardiovascular state; and (6) directing the cardiac assist pump to adjust assisted blood flow, yielding the updated transient cardiovascular state, toward the target cardiovascular state.

The present disclosure pertains to a method and system for determining the blood pressure dip of a subject based on features extracted from information generated by an on-body sensor system. The on-body sensor system includes a photoplethysmographic (PPG) sensor and a motion sensor. Blood pressure variation is captured throughout the day and utilized along with determinations of whether a subject is asleep or awake. The blood pressure determinations collected throughout the day, along with determinations of sleep periods, are used to determine a blood pressure dip for the day the on-body sensor system is worn.

There is provided a blood pressure monitor for use in measuring the blood pressure of a subject, the blood pressure monitor comprising a cuff that is configured to be placed around a body part of the subject and inflated to apply pressure to the body part; a pressure sensor that is configured to provide measurements of the pressure in the cuff; a plethysmography sensor comprising a coil having one or more windings that is configured to provide an output signal indicating the volume of the body part of the subject and/or changes in the volume of the body part; and a processing unit that is configured to determine the blood pressure of the subject from the measurements of the pressure in the cuff and the measurements of the volume of the body part and/or the changes in the volume of the body part. A corresponding method claim is also provided.

Disclosed embodiments relate to apparatuses and methods for a skin perfusion pressure determination device. In some embodiments, a skin perfusion pressure determination device can include a sensor module having a first sensor for sensing a first parameter associated with a pressure exerted on a target area by the sensor module and a second sensor for sensing a second parameter associated with an amount of blood perfusion at the target area. In some embodiments, the first sensor and the second sensor can be arranged such that, when the sensor module is pressed against the target area the first sensor produces an output corresponding to the sensed first parameter and the second sensor produces an output corresponding to the sensed second parameter.

Physiological signal processing systems include a photoplethysmograph (PPG) sensor that is configured to generate a physiological waveform, and an inertial sensor that is configured to generate a motion signal. A physiological metric extractor is configured to extract a physiological metric from the physiological waveform that is generated by the PPG sensor. The physiological metric extractor includes an averager that has an impulse response that is responsive to the strength of the motion signal. Related methods are also described.

Provided is a method of determining a hemostatic pressure in a tourniquet includes: driving a limb occlusion pressure (LOP) sensor, which measures a pulse signal of a subject, at a first brightness (S1); checking whether the LOP sensor and a main body are connected to each other (S2); providing a first hemostatic pressure from the main body to the tourniquet (S3); checking, on the basis of a result value of the LOP sensor, whether a pulse of the subject is detected (S4); and, when, on the basis of the result value of the LOP sensor, the pulse of the subject is determined as “not detected,” providing a hemostatic pressure, which is obtained by increasing the current hemostatic pressure by a safe hemostatic pressure, from the main body to the tourniquet (S7).