ABSTRACT
BACKGROUND: A number of medical, mostly immune-mediated conditions call for a combination therapy consisting of plasmapheresis and haemodialysis. While the two treatments are most commonly applied separately, we describe here the technical details of providing a combined 'tandem' treatment. Method. The components of a dialyzer (polysulfon membrane) and plasma filter are serially connected by a continuous arteriovenous haemofiltration (CAVH) system. In an extracorporeal circulation, using a blood pump the patient's blood is led first to the plasma filter and then into the dialyzer. The substituate connection is located behind the plasma filter and before the dialyzer. At the beginning it is obligatory to carry out an inspection of tubing system leakages. Afterwards, the system is flushed with a heparinized (5000 IE) sodium chloride solution that is removed thereafter. During the treatment, a blood flow of 150-200 ml/min is possible. In each case, the plasmafiltration and the ultrafiltration should not exceed 25% of the blood flow. The whole time, an intermittent check of blood pressure and heart rate is necessary. The total procedure does not take longer than a routine haemodialysis (3-4 h). RESULTS: In 82 patients we performed 483 tandem treatments during the last 16 years. None of the patients had volume disturbances caused by plasma shifts and derangements of electrolytes and acid-base balance were immediately equalized. There were no episodes of hypotension or bleeding. Back-filtration did not occur. CONCLUSION: Providing both haemodialysis and plasmapheresis at the same time reduces treatment time and thus, overall cost of the treatment. This retrospective analysis shows the tandem treatment to be safe and effective.
