摘要:
An extracorporeal blood treatment apparatus is provided comprising a filtration unit (2) connected to a blood circuit (17) and to a dialysate circuit (32), a preparation device (9) for preparing and regulating the composition of the dialysis fluid, and a sensor (11) for measuring conductivity of the dialysate (i.e. spent dialysis fluid); a control unit (12) configured for setting a sodium concentration in the dialysis fluid and after setting the dialysis fluid at the initial set point, circulating the dialysis fluid and/or the substitution fluid, measuring an initial conductivity value of the dialysate at the beginning of the treatment, and calculating, based on the measured initial conductivity value of the spent dialysis fluid and on the corresponding conductivity value of the dialysis fluid, the value of the initial plasma conductivity, said circulating the dialysis fluid up to the calculating of the initial plasma conductivity being performed maintaining the dialysis fluid conductivity substantially constant.
摘要:
An extracorporeal blood treatment apparatus is provided comprising a filtration unit (2) connected to a blood circuit (17) and to a dialysate circuit (32), a preparation device (9) for preparing and regulating the composition of the dialysis fluid; a control unit (12) is configured for setting a sodium concentration value for the dialysis fluid in the dialysis supply line (8) at a set point; the setting of the sodium concentration includes the sub-step of calculating the sodium concentration value as an algebraic sum of a main contribution term based on the blood plasma conductivity and of an adjustment contribution term based on a concentration of at least a substance in the dialysis fluid chosen in the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate, and phosphate.
摘要:
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.
摘要:
An apparatus (1) is described for extracorporeal blood treatment, comprising a treatment unit (2), an extracorporeal blood circuit (8) and a fluid evacuation line (10). A venous chamber (12) is placed in a blood return line (7) and is arranged in use to contain a gas in an upper portion (120) and blood at a predetermined level in a lower portion. The apparatus (1) comprises a control unit (21) connected to a first pressure sensor (14) and configured to: receive from the first pressure sensor (14) a first signal (P1(t)) relating to a time variable pressure (P(t)) of the blood flow; calculate a phase shift (θ) between the first signal (P1(t)) and a reference signal (P2(t)) correlated to the time variable pressure (P(t)) detected at a location distinct from the upper portion (120) of the chamber (12); monitor the volume (V) of gas in the upper portion (120) of the chamber (12) through the phase shift (θ).
摘要:
A monitoring device (7) operates an input block (30) to acquire a pressure signal from a pressure sensor (6a-6c) in an apparatus for extracorporeal blood processing connected to the vascular system of the subject. A processing block (34) 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 (35) 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 (7) 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.
摘要:
A monitoring device (7) 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 (7) has a first input block (50) for obtaining a first pressure signal (y) from a first pressure sensor (6a) in the extracorporeal blood circuit, and a second input block (51) for obtaining a second pressure signal (w) from a second pressure sensor (6b) in the treatment fluid supply system. An emulation block (56) 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 (6a), and a filtering block (53) 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 (1b). A pulse detection block (54) processes the filtered signal (yf) for detection of subject pulses originating from the subject.
摘要:
A cardiac-activity based prediction of a rapid drop in a patient's blood pressure during extracorporeal blood treatment is disclosed. A proposed alarm apparatus includes a primary beat morphology analysis unit bank of secondary analysis units and an alarm generating unit. The primary beat morphology analysis unit discriminates heart beats in a received basic electrocardiogram signal, classifies each beat into one out of at least two different beat categories, and associates each segment of the signal with relevant event-type data. The event-type data and the basic electrocardiogram signal together form an enhanced electrocardiogram signal, based upon which the primary beat morphology analysis unit determines whether one or more secondary signal analyses should be performed. Depending on the enhanced electrocardiogram signal's properties, the bank of secondary analysis units performs none, one or more of up to at least two different types of secondary analyses, and for each analysis performed produces a respective test signal. The alarm generating unit receives the test signals, and triggers an alarm signal indicative of an estimated rapid blood pressure decrease, if at least one alarm criterion is fulfilled.
摘要:
An extracorporeal blood treatment apparatus includes a filtration unit (2) connected to a blood circuit (17) and a dialysate circuit (32), a preparation device (9) for preparing and regulating the composition of the dialysis fluid, and a sensor (11) for measuring conductivity of the dialysate (i.e. spent dialysis fluid); a control unit (12) configured for setting a sodium concentration in the dialysis fluid and after setting the dialysis fluid at the initial set point, circulating the dialysis fluid and blood through the filtration unit (2), measuring an initial conductivity value of the dialysate at the beginning of the treatment, and calculating, based on the measured initial conductivity value and on the corresponding conductivity value of the dialysis fluid, the value of the initial plasma conductivity, said circulating of the dialysis fluid up to the calculating of the initial plasma conductivity performed by maintaining the dialysis fluid conductivity substantially constant.
摘要:
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 (S3) a template signal from the signal segment, and applying a refinement processing (S6) to the resulting difference signal to generate a new template signal. By proper selection (S2) 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 (S6) 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.
摘要:
A control system (23) is arranged to control the operation of an apparatus (200) for extracorporeal blood treatment. The apparatus (200) comprises an extracorporeal blood circuit (20) and a connection system (C) for connecting the blood circuit (20) to the vascular system of a patient. The blood circuit (20) comprises a blood processing device (6), and at least one pumping device (3). 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 (20) to pump blood from the vascular system via the connection system (C) through the blood processing device (6) and back to the vascular system via the connection system (C). The control system (23) is operable to obtain measurement data from at least one energy transfer sensor (40) arranged to sense a transfer of energy between the patient and the connection system (C) or between the patient and the blood circuit (20). The control system (23) 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 (20) 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 (200) for blood treatment, such as a dialysis machine.