Gambro Lundia Ab

Gambro Ab

Vibrosense Dynamics Ab

Bo Olde

Kristian Solem

Jan P Sternby

Thomas Hertz

Mattias Holmer

Anders Wieslander

Per Hansson

Raymond Anthony Edgson

Lars-Fride Olsson

Anders Roslund

Martin Furmanski

Anders Wallenborg

Arfon Goodman-Jones

Sture Hobro

Eddie Nilsson

Leif Sörnmo

Thierry Court

David Stefani

Derek White

Eric Roussi

Michael Scarsén

Antonio Speidel

A monitoring system performs a method for detecting a disruption of a fluid connection between a first fluid containing system and a second fluid containing system. The monitoring system generates a monitoring signal which is representative of a fluid pressure in respect of the first fluid containing system and which is responsive to the disruption of the fluid connection, and a tracking signal which corresponds to and is more smoothed over time than the monitoring signal. The monitoring system further sets a detection range in a given relation to the tracking signal so that the detection range follows changes in the tracking signal, and detects a condition indicative of the disruption by comparing a current pressure value of the monitoring signal to the detection range. The monitoring system may be connected to or part of an apparatus for blood treatment and operable to detect a disconnection of an extracorporeal blood circuit from a vascular system of a patient, e.g. downstream of a blood pump in the extracorporeal blood circuit.

Detection of a disruption of a fluid connection between two fluid containing systems

A method of monitoring the integrity of a fluid connection between first and second fluid containing systems based on at least one time-dependent measurement signal from a pressure sensor in the first fluid containing system. The pressure sensor detects first pulses originating from a first pulse generator in the first fluid containing system and second pulses originating from a second pulse generator in the second fluid containing system. A parameter value representing a distribution of signal values within a time window is calculated by analyzing the measurement signal in the time domain and/or by using information on the timing of the second pulses in the measurement signal. The parameter value may be calculated as a statistical dispersion measure of the signal values, or from matching the signal to a predicted temporal signal profile of the second pulse. The integrity of the fluid connection is determined from the parameter value.

Methods and devices for monitoring the integrity of a fluid connection

A monitoring arrangementis configured to predict a rapid symptomatic drop in a subject's blood pressure, e.g. during a medical treatment or when operating aircraft. To this aim, a pulse shape parameter (p) with respect to a peripheral body part () of the subject (P) is repeatedly registered by means of a pulse oximetry instrument () adapted to detect light response variations in blood vessels. A respective pulse magnitude measure is calculated based on each of a number of received pulse shape parameters (p), and a statistical dispersion measure is calculated based on the thus-calculated pulse magnitude measure. It is investigated whether or not the statistical dispersion measure fulfils a decision criterion relative to a reference measure. An output signal (&#x3b1;) is generated if the decision criterion is found to be fulfilled.

Apparatus and method for prediction of rapid symptomatic blood pressure decrease

A filtering device receives a pressure signal (P) from a pressure sensor in a fluid containing system, the pressure signal (P) comprising first pulses originating from a first periodic pulse generator and second pulses. The device acquires a reference signal which is indicative of a current operating frequency of the first periodic pulse generator. The device identifies, based on the reference signal, a plurality of harmonics (-) associated with the current operating frequency, computes correlation values (&#x3bb;-&#x3bb;) between the harmonics and the pressure signal (P) within a time window in the pressure signal (P), and generates a filtered signal by subtracting, as a function of the correlation values (&#x3bb;-&#x3bb;), the harmonics from the pressure signal (P). The use of correlation values is a direct, fast, robust and computation-efficient approach for estimating the signal contribution (d) from first pulses in the pressure signal (P).

Filtering of pressure signals for suppression of periodic pulses

A monitoring system () performs a method for detecting a disruption of a fluid connection between a first fluid containing system and a second fluid containing system. The monitoring system generates a monitoring signal (M) which is representative of a fluid pressure in respect of the first fluid containing system and which is responsive to the disruption of the fluid connection, and a tracking signal (T) which corresponds to and is more smoothed over time than the monitoring signal (M). The monitoring system () further sets a detection range (ML, MH) in a given relation to the tracking signal (T) so that the detection range (ML, MH) follows changes in the tracking signal (T), and detects a condition indicative of the disruption by comparing a current pressure value of the monitoring signal (M) to the detection range (ML, MH). The monitoring system () may be connected to or part of an apparatus for blood treatment and operable to detect a disconnection of an extracorporeal blood circuit from a vascular system of a patient, e.g. downstream of a blood pump in the extracorporeal blood circuit.

A monitoring device implements a monitoring method that comprises: activating a first monitoring technique that operates to detect the disruption and generate a corresponding alarm signal while a second monitoring technique is deactivated, obtaining at least one of a first count of false alarms generated by the primary monitoring technique and a second count of false alarms generated by the second monitoring technique if activated, and selectively, based on at least one of the first and second counts, activating the second monitoring technique to operate, instead of or jointly with the first monitoring technique, to detect the disruption and generate the corresponding alarm signal. The monitoring device may be connected to or part of an apparatus for blood treatment and operable to detect a disconnection of an extracorporeal blood circuit from a vascular system of a patient, e.g. a venous-side disconnection.

A monitoring device is included in a medical system to implement a method for prediction of a rapid symptomatic drop in a subject's blood pressure, e.g. during a medical treatment such as dialysis. To this aim, a pulse shape parameter (pPS) with respect to a pulse generator of the subject is registered by means of a pressure sensor arranged in an extracorporeal blood flow circuit coupled to a cardiovascular system of the subject (P). The pressure sensor is configured to detect pressure variations in blood vessels of the subject (P). It is investigated, during measurement period, whether or not one or more of the pulse shape parameters fulfil a decision criterion. An output signal (a) is generated if the decision criterion is found to be fulfilled, to indicate a predicted rapid symptomatic blood pressure decrease in the subject (P). The decision criterion may operate on pulse magnitude measures calculated for the received pulse shape parameters (pPS), or statistical dispersion measures calculated based on the thus-calculated pulse magnitude measures.

A monitoring device operates on a pressure signal from a blood processing apparatus which has an extracorporeal blood circuit for pumping blood through a dialyzer, and a treatment fluid supply system for pumping a treatment fluid through the dialyzer. The monitoring device has a first input block for obtaining a first pressure signal, and a second input block for obtaining a second pressure signal. An emulation block generates, as a function of the second pressure signal, an emulated first pressure signal which emulates a concurrent signal response of the first pressure sensor, and a filtering block generates a filtered signal as a function of the first pressure signal and the emulated first pressure signal, so as to suppress, in the filtered signal compared to the first pressure signal, signal interferences originating from the treatment fluid supply system. A pulse detection block processes the filtered signal for detection of subject pulses.

Detecting pressure pulses in a blood processing apparatus

A monitoring device detects a disruption of a fluid connection between first and second fluid containing systems using one or more pressure sensors arranged in the first fluid containing system to detect first pulses from the first fluid containing system and second pulses from the second fluid containing system. The monitoring device receives () pressure signal(s) from the pressure sensor(s), populates () signal vectors by signal segments in the pressure signal(s) and computes () one or more eigenvectors and/or one or more eigenvalues for the signal vectors by a source separation algorithm. The monitoring device detects () the disruption based on a monitoring parameter, which is computed as a function of the eigenvector(s) and/or eigenvalue(s) to be responsive to the second pulses in the pressure signal(s). The monitoring device may be associated with or included in an apparatus for extracorporeal blood processing, such as a dialysis machine.

Device and method for disruption detection

A control system () is arranged to control the operation of an apparatus () for extracorporeal blood treatment. The apparatus () comprises an extracorporeal blood circuit () and a connection system (C) for connecting the blood circuit () to the vascular system of a patient. The blood circuit () comprises a blood processing device (), and at least one pumping device (). The control system is operable to switch between a pre-treatment mode and a blood treatment mode. The blood treatment mode involves operating the blood circuit () to pump blood from the vascular system via the connection system (C) through the blood processing device () and back to the vascular system via the connection system (C). The control system () is operable to obtain measurement data from at least one energy transfer sensor () arranged to sense a transfer of energy between the patient and the connection system (C) or between the patient and the blood circuit (). The control system () is configured to, in the pre-treatment mode, process the measurement data for identification of a characteristic change indicating a connection of the blood circuit () to the vascular system of the patient, and, upon such identification, take dedicated action. The action may involve activating at least part of a patient protection system and/or enabling entry into the blood treatment mode. The control system may be included in an apparatus () for blood treatment, such as a dialysis machine.

Controlling an apparatus for fluid transfer to and/or from a subject

A device is configured to monitor a cardiovascular property of a subject. The device obtains measurement data from a primary pressure wave sensor arranged to detect pressure waves in an extracorporeal fluid circuit in fluid communication with the cardiovascular system of the subject. The device has a signal processor configured to generate a time-dependent monitoring signal based on the measurement data, such that the monitoring signal comprises a sequence of heart pulses, wherein each heart pulse represents a pressure wave originating from a heart beat in the subject; determine beat classification data for each heart pulse in the monitoring signal; and calculate, based at least partly on the beat classification data, a parameter value indicative of the cardiovascular property. The beat classification data may distinguish between heart pulses originating from normal heart beats and heart pulses originating from ectopic heart beats. The cardiovascular property may be an arterial status of the cardiovascular system, a degree of calcification in the cardiovascular system, a status of a blood vessel access used for connecting the extracorporeal fluid circuit to the cardiovascular system, a heart rate variability, a heart rate, a heart rate turbulence, an ectopic beat count, or an origin of ectopic beats. The device may be attached to or part of a dialysis machine.

Monitoring a property of the cardiovascular system of a subject

An apparatus () is described for extracorporeal blood treatment, comprising a treatment unit (), an extracorporeal blood circuit () and a fluid evacuation line (). A venous chamber () is placed in a blood return line () and is arranged in use to contain a gas in an upper portion () and blood at a predetermined level in a lower portion. The apparatus () comprises a control unit () connected to a first pressure sensor () and configured to: receive from the first pressure sensor () a first signal (P()) relating to a time variable pressure (P(t)) of the blood flow; calculate a phase shift (&#x3b8;) between the first signal (P()) and a reference signal (P()) correlated to the time variable pressure (P(t)) detected at a location distinct from the upper portion () of the chamber (); monitor the volume (V) of gas in the upper portion () of the chamber () through the phase shift (&#x3b8;).

Apparatus for extracorporeal blood treatment and a control method therefor

A filtering device receives a signal from a pressure sensor in an extracorporeal fluid circuit connected to a subject and processes the signal to separate physiological pulses, e.g. from the subject's heart, from interference pulses, e.g. from a pump in the fluid circuit. The device repeatedly (iteratively) processes a signal segment by alternately subtracting (S) a template signal from the signal segment, and applying a refinement processing (S) to the resulting difference signal to generate a new template signal. By proper selection (S) of the initial template signal, consecutive difference signals will alternately approximate the sequence of interference pulses in the signal segment and the sequence of physiological pulses in the signal segment. The refinement processing (S) aims at alternately cleaning up unwanted residuals from interference pulses and physiological pulses, respectively, in the respective difference signal, so as to improve the accuracy of the template signal between the subtractions.

Separation of interference pulses from physiological pulses in a pressure signal

A monitoring device () operates on a pressure signal from a blood processing apparatus, e.g. a dialysis machine, which has an extracorporeal blood circuit connected to a vascular system of a subject for pumping blood through a dialyzer, and a treatment fluid supply system for pumping a treatment fluid through the dialyzer. The monitoring device () has a first input block () for obtaining a first pressure signal (y) from a first pressure sensor () in the extracorporeal blood circuit, and a second input block () for obtaining a second pressure signal (w) from a second pressure sensor () in the treatment fluid supply system. An emulation block () generates, as a function of the second pressure signal (w), an emulated first pressure signal (y) which emulates a concurrent signal response of the first pressure sensor (), and a filtering block () generates a filtered signal (y) as a function of the first pressure signal (y) and the emulated first pressure signal (y), so as to suppress, in the filtered signal (}y) compared to the first pressure signal (y), signal interferences originating from the treatment fluid supply system (). A pulse detection block () processes the filtered signal (y) for detection of subject pulses originating from the subject.

A monitoring device () operates an input block () to acquire a pressure signal from a pressure sensor (-) in an apparatus for extracorporeal blood processing connected to the vascular system of the subject. A processing block () repeatedly processes the pressure signal for generation of a time-sequence of parameter values indicative of pressure pulsations originating from heartbeats in the subject, and an evaluation block () evaluates the parameter values for detection of cardiac arrest and, if cardiac arrest is detected, generates a dedicated alarm signal. To reduce the risk for false positives without increasing the risk for false negatives, the monitoring device () may acquire and process more than one pressure signal, and/or perform an initial viability check before the monitoring is initiated to ensure that pressure pulsations originating from heartbeats are detectable in the pressure signal(s), and/or separate the monitoring of the pressure signal(s) into a detection phase performed during regular operation of a blood pump in the apparatus, and a verification phase performed during a temporary shutdown of the blood pump.

Growing community of inventors

Lund, Sweden

Bo Olde