Abstract:
A method and a hemodialysis machine provide for at least partial emptying of an extracorporeal blood circulation after patient blood in the circulation has been returned to the patient via an infusion liquid which displaces the blood. The method includes emptying at least a blood chamber of a hemodialyzer subdivided by a semipermeable membrane into the blood chamber and a dialysis fluid chamber without additionally connecting an arterial blood line and a venous blood line of the circulation to one another. The arterial blood line is actively or passively aerated at a first point and the venous blood line is actively or passively aerated at a second point. The infusion liquid is emptied through the membrane into the dialysis fluid chamber and then via a dialysis fluid discharge line. The method is operable by a control program that runs automatically without requiring any manual input after activation of the program.
Abstract:
The present invention relates to a method for checking and/or monitoring the correct operation of an adding device of a medical apparatus, wherein the medical apparatus includes an extracorporeal circuit with which the adding device is connected such that an agent can be introduced into the extracorporeal circuit by means of the adding device, the pressure loss in the extracorporeal circuit being measured and evaluated for checking and/or monitoring the correct operation of the adding device. In accordance with the invention, the adding device for this purpose generates an oscillating pressure course.
Abstract:
Method and apparatus for controlling the dialysate flow in a dialysis device. A change of the value of a control factor, caused by a variation of a property of the dialysate or of the blood or by a change of the dialysate flow, is determined in order to control the dialysate flow. The control factor is a measure for the exchange of substances via the dialyzer and thus the effectiveness of the dialyzer. If the change of the value of the control factor exceeds a limit, the dialysate flow is increased. On the other hand, the dialysate flow is reduced if the change of the value of the control factor falls short of the limit range.
Abstract:
A method and a device for recognition of paravasal bleeding upon a supplying of blood to a vascular access via a line and/or upon the removal of blood from a vascular access via a line, particularly paravasal bleeding during extra-corporeal blood treatment, such as for hemodialysis, hemofiltration or hemodiafiltration is provided. A device for extra-corporeal blood treatment, particularly for hemodialysis, hemofiltration or hemodiafiltration, comprising a device for recognition of paravasal bleeding is also provided. The method and the device are based on the change of arterial pressure in the arterial branch or the venous pressure in the venous branch of the extra-corporeal circuit being registered during the extra-corporeal blood treatment. If paravasal bleeding occurs during the blood treatment, the positive dynamic pressure on the line leading to the vascular access rises on the venous cannula during the extra-corporeal blood treatment, or the suction pressure on the line leaving the vascular access, such as the arterial cannula during extra-corporeal blood treatment, rises; that is, the suction pressure becomes more negative. The pressure rise begins moderately at first and then becomes increasingly greater. Decisive for the method and the device, therefore, is that pressure changes that come from a pressure level exhibiting a large difference from the reference value find stronger consideration than those that come from a pressure level that exhibits only a minor difference from the reference value.
Abstract:
The invention relates to a device and to a method for monitoring access to vessels during extracorporeal blood treatment. The invention forms a loop in the arterial and/or venous line and provides device for fixing a section of the line in a loop. When the line is stressed under tension, the loop contracts and the line finally kinks. The modification of the diameter of the line and the formation of a kink in the line leads to a rise of pressure in the line, which is monitored by a pressure monitoring device. If the pressure exceeds a predetermined threshold value, the aspirating cannula is in danger of slipping out of the vessel access or has partially or completely slipped out, thus allowing the threshold value to be determined for alarms.
Abstract:
The invention relates to a method and a device for monitoring a vascular access during an extracorporeal blood treatment. The method and the device according to the invention are based on the monitoring of the difference between the venous pressure measured by a venous pressure sensor and the arterial pressure measured by an arterial pressure sensor (in the extracorporeal blood circuit. According to the method and the device according to the invention, a test function describing disturbances in the extracorporeal blood circuit is determined. Said test function is used to determine a noise-free differential pressure from the measured venous and arterial pressure, said differential pressure being evaluated in an arithmetic and evaluation unit to identify a defective vascular access.
Abstract:
The invention relates to a process for monitoring the supply of substitution fluid upstream or downstream of a dialyser or filter arranged in an extracorporeal blood stream. One embodiment provides, for the detection of predilution or postdilution, for measuring the pressure in the blood stream downstream of the dialyser or filter, predilution or postdilution being recognized on the basis of the change in pressure following the shutting off and/or starting up of the substituate pump provided for conveying the substitution fluid. Another embodiment provides for recognizing predilution or postdilution on the basis of the comparison of the oscillating pressure signal attributable to the substituate pump to a characteristic reference signal. The characteristic reference signal to which the pressure signal of the substituate pump is compared is preferably the oscillating pressure signal of a blood pump arranged in the blood stream for conveying the blood upstream of the dialyser or filter. In addition, the invention relates to an extracorporeal blood treatment device with a facility for detecting predilution or postdilution, which device operates according to the processes detailed above.
Abstract:
The present invention relates to a method for regulating supply of substituate in an extracorporeal blood treatment with an extracorporeal blood treatment apparatus comprising a dialyzer divided by a semipermeable membrane into a blood chamber and a dialyzing fluid chamber and a device for supplying substituate. Moreover, the present invention relates to an extracorporeal blood treatment apparatus having a device for regulating supply of substituate. Regulation of supply of substituate in the extracorporeal blood treatment takes place as a function of the rheological loading of the dialyzer. To regulate supply of substituate during extracorporeal blood treatment, rheological loading of the dialyzer is determined from transmembrane pressure on the dialyzer and flow resistance of the dialyzer and substituate rate is increased or reduced according to the loading. The selection of dialyzer parameters or blood parameters is therefore no longer necessary and the distinction between pre-dilution and post-dilution is also made obsolete.
Abstract:
The invention relates to a method and a hemodialysis machine for at least partial emptying of an extracorporeal blood circulation after the blood of a patient in the extracorporeal blood circulation has been returned to the patient with the help of an infusion liquid which displaces the blood and after the patient has been separated from the extracorporeal blood circulation. The object of the invention is to empty at least the blood chamber of a hemodialyzer (1) that is subdivided by a semipermeable membrane (2) into a blood chamber (3) and a dialysis fluid chamber (4) without additionally connecting the arterial blood line (5) and the venous blood line (7) of the extracorporeal blood circulation to one another. To do so, the arterial blood line (5) is actively or passively aerated at a first point (50) and/or the venous blood line (7) is actively or passively aerated at a second point (40) and the liquid is emptied through the semipermeable membrane (2) into the dialysis fluid chamber (4) and a dialysis fluid discharge line (21) leaving this chamber. The inventive method can take place here through a control program that runs automatically in the control unit (30) of a hemodialysis machine without requiring special operating steps by the operating person after activation of the program.
Abstract:
This invention relates to a method for clearing a wetted hydrophobic filter, in which in a first step the air permeability of the hydrophobic filter is monitored and in which in a second step the hydrophobic filter is cleared by means of a connected air pump, if it is detected that the hydrophobic filter is clogged. Furthermore, the invention relates to an apparatus for performing this method.