摘要:
An arterial needle removes blood from the access to an extracorporeal circuit comprising a dialyzer and a venous needle returns the blood to the access site. Blood passes along one side of the membrane of the dialyzer and dialysis fluid along the other side. Fistula or access recirculation is detected by changing the blood flow rate, monitoring the concentration of a substance in the dialysate emitted from the dialyzer and correlating a change in the concentration to the change of the blood flow rate.
摘要:
The heart produces a pressure wave which passes via the blood vessel access (1, 14) and is sensed by a pressure detector (4, 15) on the other side of the blood vessel access. The signal obtained comprises interference signals which are separated via a processing arrangement (25) in order to obtain the pulse signal. Absence of the pulse signal indicates a malfunction in the blood vessel access. A blood pump in an extracorporeal blood circuit can be used as a pressure wave generator.
摘要:
Procédé de détermination d'un paramètre significatif de l'efficacité d'un traitement extracorporel du sang consistant à faire circuler de part et d'autre de la membrane semi-perméable d'un échangeur à membrane le sang d'un patient et un liquide de traitement, caractérisé en ce qu'il comporte les étapes de :
faire circuler dans l'échangeur un liquide de traitement ayant une caractéristique ayant une valeur nominale sensiblement constante en amont de l'échangeur; faire varier la valeur de la caractéristique en amont de l'échangeur puis rétablir la caractéristique à sa valeur nominale en amont de l'échangeur; mesurer et mettre en mémoire une pluralité de valeurs prises par la caractéristique du liquide de traitement en aval de l'échangeur en réponse à la variation de la valeur de cette caractéristique provoquée en amont de l'échangeur; déterminer la superficie d'une zone de perturbation aval délimitée par une ligne de base et une courbe représentative de l'évolution par rapport au temps de la caractéristique ; et calculer le paramètre significatif de l'efficacité d'un traitement à partir de la superficie de la zone de perturbation aval et de la superficie d'une zone de perturbation amont délimitée par une ligne de base et une courbe représentative de l'évolution par rapport au temps de la caractéristique en amont de l'échangeur.
摘要:
Method and device for measuring the concentration of urea or a similar substance, in a composite solution, particularly a dialysis solution, by catalytic decomposition of urea by urease. The differential conductivity of the reacted and unreacted solution is measured and is proportional to the urea concentration. The decomposition occurs according to the reaction: (NH2)2 CO + CO2 + 3H2O → 2NH4+ + 2HCO¿3?- (5). By the addition (41, 60) of carbon dioxide gas and by catalyzation with the enzyme urease, the reaction is displaced to the right, which means that said proportionality is valid over a large range of urea concentrations, up to and exceeding 35 mM. The addition of carbon dioxide gas also ensures sufficiently low pH-value in the solution in order to avoid precipitation of calcium carbonate.
摘要:
System and method for monitoring a fluid flow in a dialysis machine, comprising: constant flow means (4, 5) for feeding the dialysis fluid to a dialyzer (3) and for feeding the dialysis fluid from the dialyzer to a waste or similar. Each constant flow means comprises a restrictor (6, 7), a pump (10, 11) and a pressure sensor (8, 9) interposed therebetween, and means for controlling each pump (10, 11) for maintaining a substantially constant pressure as measured by each pressure sensor resulting in a substantially constant flow therethrough. Moreover, there are calculating means (20, 21, 22, 23, 24) for calculating dialysis fluid flow rates before and after the dialyzer (3) by means of pressure values obtained from the same pressure sensors (8, 9), according to the formula P - P0 = k * Qn where P is a pressure on one side of the restritor, P¿0? is a back pressure on the other side of the restrictor, k is a characteristic coefficient for the restrictor, Q is the fluid flow through the restrictor and n is a characteristic exponent for the restrictor.
摘要:
A system and kit for cytotoxicity tests comprising those substances (1-7) necessary for the test, such as necessary chemical compounds and test cells, and preferably also a test plate and other instruments necessary for the test, such as pipettes (9) or similar, characterized by means (10-12) for storing a mixture (2) of test cells and a cell-culture medium at a lowered temperature, preferably corresponding to normal refrigerator temperature. The invention further includes a method for storing cells for cytotoxicity tests during transport, which cells are intended for the system and kit with substantially maintained biological properties, characterized in that they are transported at a lowered temperature, preferably at substantially normal refrigerator temperature.
摘要:
The catheter protector consists of a transparent plastic bag (7), with an upper hole (8) surrounded by an adhesive (9) and preferably one lower opening (11) which is closeable by means of a closure (12) of the zip type. The bag comprises a desiccant (14) for absorption of moisture within the bag. The bag is fastened to the skin surrounding a catheter entrance point (2) and protects the catheter connectors (3,4) between uses, whereby showering etc. is made possible.