Liver dialysis
The liver dialysis is to bridge on techniques of purification processes in renal failure, which is to help the so-called dialysis -based therapy concept that patients with liver failure, the time to transplantation or to relieve the liver to allow regeneration. The liver can heal itself with a damage of 90 percent in some cases, even themselves, if enough time is available. Through the self-healing transplants can be possibly avoided.
Method
There are basically two types of liver dialysis method: 1) the cell-based - bioartificial method and 2) cell-free - artificial systems.
The cell-free systems include the most widely used so-called MARS method, an albumin dialysis, and the Prometheusverfahren introduced later ( both use human serum albumin for transport). The mother of these methods, the single pass albumin dialysis is also called SPAD.
In some clinics even the method of Bilirubinadsorption takes place, which, strictly speaking, but is not a real liver support method.
With regard to the application of the method to other indications have shown from a purely acute liver failure to chronic liver failure, the use of Poisoning is already occupied and by the Food and Drug Administration ( FDA).
The cost of the 'real' procedure may be charged the clinics as additional remuneration ( ZE2006 -10) since 2004 on the DRG system ( Diagnosis Related Groups).
The bioartificial procedures have not let the world despite the use of various scientific working groups in their efficacy and safety evidence. In particular, the additional synthesis performance is so far not been sufficiently demonstrated. The cost of these organic methods today are in no relation to the discussions in health care. A lot of experience in this field has gathered in Berlin with the Modular Extracorporeal Liver Support ( MELS ), the Charité.
Molecular Adsorbents Recirculation System (MARS)
The MARS method (Molecular Adsorbent Recirculation System) Gambro Hospal GmbH is a further development of the original idea of albumin dialysis, known as SPAD. The desire for a standardized system of longer duration and low albumin consumption has led to the development up to the MARS system.
Basically, the MARS system is closely modeled on the known dialysis system. The blood is diverted past a semipermeable membrane, where it can its molecules, to about 55 kD, leave. Among them there are usually many toxins that accumulate in the liver failure in the patient's blood. The albumin solution (yellow circuit) transports the toxins on to a so-called low-flux membrane in order there to replace the smaller molecules (urea, creatinine, electrolytes). Also an accounting of the patient can be carried out here. The next two purification steps are the delivery of larger molecular weight substances in a Kohleadsorber and an ion exchanger. The then nearly purified albumin, the MARS membrane are fed and continue to gather toxins there so again.
The MARS method is used 3-10 days 8-24 hours per day and in general.
Single Pass Albumin Dialysis ( SPAD)
When an attempt is made by means of a SPAD similar procedure as in MARS, to remove albumin from the blood. A variant of the SPAD is the Continuous Single Pass Albumin Dialysis ( CSPAD ).
Prometheus
Developed by Fresenius scientists in cooperation with the Danube University Krems Prometheus system is among the newest liver support systems on the market. The Prometheus system combines a typical dialysis procedure with an adsorber.