270 results about "Cuff pressure" patented technology

A method for controlling breathing gas flow of a ventilator for assisted or controlled ventilation of a patient as a function of a tracheobronchial airway pressure of the patient. A ventilator tube, such as a tracheal tube or tracheostomy tube, can be introduced into a trachea of the patient and subjected to the breathing gas, and has an inflatable cuff and at least one lumen that is continuous from a distal end of the tube to a proximal end of the tube. An apparatus detects an airway pressure, in which the tracheobronchial airway pressure is ascertained by continuous or intermittent detection and evaluation of an intra-cuff pressure prevailing in the cuff of the tube inserted into the trachea. The breathing gas flow of the ventilator is controlled as a function of the intra-cuff pressure detected.

Described herein is an apparatus that includes an endotracheal tube or airway device having a proximal end and a distal end and an occlusion cuff. The occlusion cuff includes a sensor for helping determine proper endotracheal or airway device placement.

An automatic skin perfusion measuring device automatically analyzes perfusion measurements to identify motion artifact and SPP values. Motion artifact is ignored. Perfusion measurements are designated as SPP values if various criteria are met. SPP value criteria pertain to factors including cuff pressure, perfusion, perfusion change percentages relative to previous and subsequent perfusion measurements, and whether perfusion measurements are increasing or decreasing relative to previous and subsequent perfusion measurements.

An automatic skin perfusion measuring system including instrumentation that automatically analyzes perfusion measurements to identify motion artifact and SPP values and a sensor placement device is provided. The instrumentation is configured to ignore motion artifact. Perfusion measurements are designated as SPP values if various criteria are met. SPP value criteria pertain to factors including cuff pressure, perfusion, perfusion change percentages relative to previous and subsequent perfusion measurements, and whether perfusion measurements are increasing or decreasing relative to previous and subsequent perfusion measurements. The sensor placement device assures reliable data is produced when multiple measurements are desired.

Apparatus, method, and software for electrocardiogram-assisted non-invasive arterial blood pressure d stiffness measurement is disclosed including brachial cuff with flexible electrodes, control box with rigid electrodes, and associated hardware / software. Cuff is wrapped around upper arm while electrodes on device are touched with fingers of other hand. Device acquires simultaneous ECG / oscillometric data during cuff deflation. Processing unit determines ECG R-peak positions to isolate arterial pulses and calculate pulse transit time. Change in pulse amplitude as function of cuff pressure is used for constructing oscillometric envelope and calculating blood pressure using empirical coefficients. Change in pulse transit time as function of cuff pressure is used independently for constructing pulse transit time envelopes and finding blood pressure with / without empirical coefficients. Fusion algorithm combines results for robust blood pressure and vessel stiffness evaluation. Device sends physiological information to personal computer / smartphone wirelessly, for further analysis. Computer / smartphone transmits information to third party for patient management.

An electric blood pressure measurer without wound based on the algorithm for processing the pulse wave signals of inflatable cuff is disclosed. Its measuring steps include invoking the blood pressure measuring program module, running it, inflating the cuff to a certain pressure, releasing air by predefined steps, synchronously detecting the pressure of cuff and pulse wave for each step, monitoring and judging the time and pressure variation, determining if the measurement is stopped, processing the recorded pulse waves to obtain average pressure, and calculating systolic pressure and diastolic pressure.

A system and method of enhancing a blood pressure signal is disclosed. The volume of an artery in a finger is measured by a photo-plesthysmographic (PPG) system, which produces a PPG signal. This PPG system is placed inside a cuff, and the cuff pressure is controlled by the PPG signal. The portion or component of the PPG signal having a frequency higher than a predefined threshold frequency is then modified or enhanced, such as by multiplying the high frequency component by a calibration factor. A blood pressure signal is then calculated using the cuff pressure and the modified PPG signal. A blood pressure contour curve may then be generated, and a variety of parameters may be calculated using the curve.

A method and system for operating a non-invasive blood pressure monitor that utilizes an SpO2 plethysmograph signal to determine the initial inflation pressure for the blood pressure cuff of the NIBP monitor. A pulse sensor is placed on the patient's limb distal to the blood pressure cuff such that as the blood pressure cuff is inflated, the pulse signals from the pulse sensor will be reduced. When the blood pressure cuff reaches systolic pressure, the pulse signals from the pulse sensor will be initially attenuated and eventually eliminated, thus providing an indication that the cuff pressure has reached systolic pressure for the patient. The central processor of the NIBP monitor compares the pulse signals during cuff inflation to an average pulse signal and terminates the inflation of the blood pressure cuff upon sufficient attenuation. The use of the SpO2 plethysmograph signal to determine the initial inflation pressure reduces both the over-inflation of the blood pressure cuff and the under-inflation of the blood pressure cuff which increases the rate at which the blood pressure measurement can be made while increasing patient comfort.

Improved tourniquet apparatus for measuring a patient's limb occlusion pressure includes an inflatable tourniquet cuff for encircling a limb at a location and to which a tourniquet instrument is releasably connectable. The instrument includes pressure sensing for producing a cuff pressure signal indicative of the level of pressure in the cuff, a pressure regulation mechanism communicating with the cuff and responsive to the cuff pressure signal for moving fluid into and out of the cuff, thereby regulating the pressure in the cuff, a blood flow transducer for producing a blood flow signal indicative of blood flow past the cuff, and limb occlusion pressure means responsive to the blood flow signal and the cuff pressure signal for increasing the cuff pressure level until blood flow indicated by the blood flow signal decreases to a level less than a minimum detection threshold, and then suspending fluid movement into and out of the cuff to produce a limb occlusion pressure value that is indicative of a pressure in the cuff when the fluid motion is suspended.

A method and device for measuring the blood pressure of artery and its personalized correction technique are disclosed. A series of the pressure values (P) for sleeve band and the time delay values (Tk) of the relative remote Ke's sounds are obtained. The function relation Tk(P) between said pressure change and sound delay is in turn obtained. Measuring a Tk relative to a P can calculate out the blood pressure change. A regression equation for continuous measurements of arteral blood pressure is used to obtain a personalized correction coefficient.

A method and apparatus for measuring blood pressure by the oscillometric technique. The method incorporates variable PIP's. The method comprises the steps of obtaining a value for the peak amplitude Amax of an oscillometric envelope; determining a cuff pressure, CP, which corresponds in time with Amax, this pressure representing the MAP of the subject; computing a variable value PIPSBP as a function of MAP; performing the calculation Asbp=Amax*PIPSBP to determine a systolic amplitude value Asbp along the oscillometric envelope; and determining the cuff pressure C which corresponds in time to Asbp, this value representing the systolic blood pressure (SBP) of the subject. PIP can be calculated using a piece-wise linear, polynomial, exponential or other function.

A modified laryngeal mask airway device (LMA-device) is provided with means to improve ease of insertion, reliability of function and higher seal pressure (i.e., cuff pressure ratio). The LMA-device includes an indented section of the airway tube to offer locating means and purchase for the inserting finger, and extended mask aperture bars to increase the effective ventilating area of the mask and reduce the possibility of epiglottis displacement occasioned by mask insertion. The LMA-device further includes a modification of the airway tube angle of attachment to the mask, and provision of a posterior or back-cushion covering the entire posterior surface of the mask.

The present invention provides a new multi-mode sphygmomanometer which integrates into one enclosure a full manual sphygmomanometer comprising a mechanical cuff pressure measuring and display system, a manual inflation bulb and deflation valve such elements comprising the manual / mechanical aspect of the integrated device. Within the same physical enclosure and integrated with the manual sphygmomanometer the device also comprises an electronic blood pressure measuring and monitoring device comprising electronic sensing of the pressure, electronic indication of the cuff pressure and oscillation or KS amplitudes and logic implemented in a microprocessor that automatically interprets these signals to determine the BP parameters.

A blood pressure measurement bladder (50) has a predetermined amount of air introduced and sealed therein. A CPU (30) measures in advance the P-V property. The blood pressure measurement bladder (50) is wrapped around a measurement site. By exerting pressure from the outer side to the blood pressure measurement bladder (50), the internal pressure in the blood pressure measurement bladder (50) is increased to exert pressure on the blood vessel. During this process, the cuff pressure in the blood pressure measurement bladder (50) generated by volumetric change of the blood vessel by changing the pressure exerted from the outer side to the blood pressure measurement bladder (50), and the pressure pulse wave data are detected. By adding the cuff compliance property obtained by the P-V property that was measured in advance to the detected data as a correction value of the pressure pulse wave, blood pressure is calculated.

A biosensing meter plus blood pressure measuring apparatus has a slot, an inflatable and deflatable cuff, a pressure sensor and a microprocessor. The slot is able to accept a code card with multiple parameters or a sample strip that comprises a reaction well and a plurality of electrodes thereon in contact with the reaction well. The pressure sensor is used for detecting arterial counterpressure pulses and oscillations at each of the cuff pressure deflating process. The microprocessor is used for controlling the cuff, converting counterpressure pulses and oscillations to voltage signals, processing the voltage signals into a sequence of peak amplitudes and determining a systolic pressure and a diastolic pressure. Furthermore, the microprocessor is used for reading multiple parameters in the code card to measure an analyte in an analyte-containing fluid and calculating a concentration of the analyte. When an analyte-containing fluid (normally blood) is received on the sample strip, the inspection result is obtained according to the operation procedure and parameters obtained previously by the code card. The present apparatus can monitor the blood glucose and blood pressure values at the same apparatus.

The present invention discloses a non-invasive blood pressure measurement apparatus and a safety protection method. In addition to a main pressure measurement circuit and a main microprocessor circuit, the measurement apparatus also includes an independently disposed assist pressure measurement circuit and an independently disposed assist microprocessor circuit. In normal measurement, the assist microprocessor circuit periodically samples a cuff pressure via the assist pressure measurement circuit, and compares the measured cuff pressure with a specified overpressure protection value, and if the cuff pressure exceeds the specified overpressure protection value, the assist microprocessor circuit outputs a control signal to open a deflation valve until the pressure falls to below the safety pressure. Compared with the prior art, the method for overpressure protection of the present invention is more direct and has higher accuracy of decision, leading to higher reliability of the overpressure protection and higher safety of the measurement apparatus.

An ankle-blood-pressure measuring apparatus for measuring a blood pressure of an ankle of a living subject, including an inflatable cuff which is adapted to be worn on the ankle of the subject; a cuff-pressure changing device which decreases a pressure in the cuff from a pressure higher than a systolic blood pressure of the ankle; a distal-pulse-wave detecting device which is adapted to be worn on a distal portion of the subject that is located on a distal side of the ankle and detects a distal pulse wave produced from the distal portion; an increasing-point detecting device for detecting at least one increasing point where a magnitude of the distal pulse wave continuously detected by the distal-pulse-wave detecting device when the pressure of the cuff is decreased by the cuff-pressure changing device, significantly increases; and an ankle-blood-pressure determining device which determines a pressure of the cuff when the increasing-point detecting device detects the second increasing point, as a systolic blood pressure of one of a plurality of tibial arteries of the ankle of the subject that has stenosis.

The invention relates to a blood pressure measuring module and a blood pressure measuring method. The measuring module comprises a cuff, a charging and discharging control module, a pressure detectionmodule, a pressure processing module, CPU, a sound detection module for collecting pulse sound and a sound processing module for amplifying and filtering the collected pulse sound. In one measurement, the CPU is used for searching the pulse wave and pulse sound automatically, obtaining pulse wave and pulse wave sequence corresponding to cuff pressure, pulse sound and pulse sound sequence corresponding to cuff pressure, blood pressure data of an oscillation method and blood pressure data of an auscultatory method, giving reasonable and accurate final measurement result according to comparisonto two groups of blood pressure data and judgment of signal quality, and providing reliable data for diagnosing the blood pressure condition of patients accurately. Meanwhile, the invention realizes the self-adapting charging manner of determining the charging target pressure according to the pulse amplitude, and has the advantages of simple operation as well as rapid and accurate measurement.

The invention discloses an individual adaptive pressure increasing and decreasing control method for an electronic sphygmomanometer. The method includes: continuously inflating a cuff sleeved on an upper arm for pressure increasing; detecting pulse wave signals and cuff pressure signals; calculating mean pressure Pv and heart rate S according to the pulse wave signals during pressure increasing, calculating systolic pressure Ps according to the mean pressure Pv, and setting the maximum valve Pm of cuff pressure increasing; when the pressure of the cuff reaches the maximum value Pm, by a control air valve, performing individual adaptive constant-speed pressure decreasing until pressure decreasing is completed and the control air valve is completely opened to empty air. By the individual adaptive pressure increasing and decreasing control method for the electronic sphygmomanometer and the electronic sphygmomanometer, high-quality pulse wave signals with moderate pulse waves, reasonable amplitude and evident envelop features, a premise is provided for further identification and determining of blood pressure parameters, and comfortableness of a to-be-tested person is improved during the whole test. In addition, the method is high in individual adaptive measuring capability.

An apparatus for evaluating a vascular endothelial function includes: a cuff, to be wound around a part of a body of a subject; a cuff pressure controller, configured to control a pressure of the cuff, and configured to apply continuous pressure stimulation; a cuff pressure detector, configured to detect the pressure of the cuff from output of a pressure sensor connected to the cuff; a pulse wave detector, configured to detect, from the output of the pressure sensor, pulse waves before and after the continuous pressure stimulation is applied; and an analyzer, configured to evaluate the vascular endothelial function by comparing the pulse waves detected before and after the continuous pressure stimulation is applied.

A system and method for processing a cuff pressure waveform to determine the blood pressure of a patient. The processing unit of the NIBP monitoring system receives status signals from one or more physiological parameter monitors. The physiological parameter monitors each include an operating algorithm that causes the physiological parameter monitor to generate a status signal indicating whether artifacts are present that prevent the determination of the physiological parameter. When the processing unit receives the monitoring signal from the physiological parameter monitor indicating the presence of artifacts, the processing unit adjusts the operation of the NIBP monitor. The adjustment of the NIBP monitor may be to delay the beginning of the NIBP determination cycle until artifacts are no longer present from the physiological parameter monitor or to control the cuff pressure in such a manner as to keep the patient safe and comfortable until the artifacts are no longer present.

A system and method for processing a cuff pressure waveform to determine the blood pressure of a patient. A heart rate monitor acquires the patient's heart rate. Based upon the acquired heart rate, the system selects filtering parameters for processing the cuff pressure waveform received from the patient. The filtering parameters include a high pass cutoff frequency and a low pass cutoff frequency that are determined based upon the heart rate of the patient. The low pass cutoff frequency is based upon a harmonic frequency of the heart rate while the high pass cutoff frequency is based upon the fundamental frequency of the heart rate. The high pass and low pass cutoff frequencies are used to select filtering coefficients. The high pass and low pass cutoff frequencies are selected based upon the heart rate of the patient such that the filtering adapts based on the heart rate of the patient.

A blood pressure measuring apparatus to measure blood pressure based on a change in a pressure by a cuff mounted to a subject comprises: cuff pressure controlling means for deflating the cuff after avascularization by the cuff at a body part around which the cuff is placed; detecting means for detecting the change in a pressure by the cuff and outputting the detection as an electrical signal; extracting means for extracting a pulse wave signal from the electrical signal; and calculating means for calculating a systolic blood pressure value and a diastolic blood pressure value based on a relation between a change rate of an index value which is calculated by multiplying a maximum amplitude of each pulse of the pulse wave signal by the cuff pressure corresponding to the maximum amplitude and a predetermined value. The blood pressure measuring apparatus achieves a high-speed measurement while suppressing the reduction of accuracy.

Improved tourniquet apparatus for measuring a patient's limb occlusion pressure includes an inflatable tourniquet cuff for encircling a limb at a location and to which a tourniquet instrument is releasably connectable. The instrument includes pressure sensing for producing a cuff pressure signal indicative of the level of pressure in the cuff, a pressure regulation mechanism communicating with the cuff and responsive to the cuff pressure signal for moving fluid into and out of the cuff, thereby regulating the pressure in the cuff, a blood flow transducer for producing a blood flow signal indicative of blood flow past the cuff, and limb occlusion pressure means responsive to the blood flow signal and the cuff pressure signal for increasing the cuff pressure level until blood flow indicated by the blood flow signal decreases to a level less than a minimum detection threshold, and then suspending fluid movement into and out of the cuff to produce a limb occlusion pressure value that is indicative of a pressure in the cuff when the fluid motion is suspended.

A method and apparatus for measuring blood pressure by the oscillometric technique. The method incorporates variable PIP's. The method comprises the steps of obtaining a value for the peak amplitude Amax of an oscillometric envelope; determining a cuff pressure, CP, which corresponds in time with Amax, this pressure representing the MAP of the subject; computing a variable value PIPSBP as a function of MAP; performing the calculation Asbp=Amax*PIPSBP to determine a systolic amplitude value Asbp along the oscillometric envelope; and determining the cuff pressure C which corresponds in time to Asbp, this value representing the systolic blood pressure (SBP) of the subject. PIP can be calculated using a piece-wise linear, polynomial, exponential or other function.

A central processor controlled system and test procedure for independently, contemporaneously and plethysmographically monitoring arterial blood pressure at a subject's arms and legs. Micro-controlled occluding and sensing cuffs containing sensors are inflated and deflated at each limb of a supine patient. Sensed AC and DC pressure data is wirelessly linked to the central processor where the DC sensor data is sampled to derive median filtered, fitted and derivative waveforms that are iteratively processed and scored to determine a table of sample indices indicative of lowest pressure point. Second scoring and fittings about the lowest pressure point at the DC sensor data and original occluding cuff pressure data identify each limb's systolic pressure. The derived systolic limb pressure values are then processed to determine right and left ABI values.

Every pulse wave, a constant volume control unit performs servo control while updating a servo gain such that a difference between an arterial volume shown by an arterial volume signal that is detected by an arterial volume detection circuit and a control target value of the servo control is less than a control deviation at which a rate of change of the arterial volume relative to a change in cuff pressure is deemed to be constant. Because the control deviation is the difference between the arterial volume shown by the arterial volume signal and the control target value, a blood pressure decision unit decides, as a blood pressure, the cuff pressure sequentially detected in a period during which servo control is performed, by correcting the cuff pressure using the control deviation and the rate of change deemed to be constant.

A method for measuring systolic blood pressure includes raising the cuff pressure in such a manner that two conditions are satisfied: (1) The cuff air pressure takes sufficient time to reach the SBP value to avoid blood pressure in the arteries under the PPG sensor being too low, thereby avoiding collapse of the arterioles under the PPG sensor; and (2) The increase of the cuff air pressure between the DBP value and the SBP value is not overly slow in a manner which would cause a relatively high mean blood pressure in the arteries distal to the cuff, and could lead to reduced sensitivity in detecting the restart of blood flow when the cuff air pressure decreases to just below SBP value.

A system for measuring and indicating pressure that uses as its pressure sensing element an outer resilient tube, an inner resilient tube, and a rolling diaphragm connecting the inner and outer tubes, and held inside a protective enshrouding structure where pressure applied to the annulus between the tubes causes the diaphragm to deform and roll to axial extend the outer tube by an amount proportional to the applied pressure. The structure has features that enable visual correlation of the partially rolled tube's unrolled state with the applied pressure. The system can be incorporated into a syringe to create a pressure measuring syringe for inflating endotracheal cuffs while providing a reading of the cuff pressure.