Multicentric experience with combined hemodialysis/hemoperfusion in chronic uremia

Routine Clinical Applications of Hemodialysis-Hemoperfusion in Chronic Renal Failure: Case Reports

Five hemodialysis patients were treated with combined hemodialysis-hemoperfusion with their conventional hemodialyzer plus a 70-gram ultrathin collodion coated activated charcoal device for a total of 63 months. Indications for this therapy included pericarditis, peripheral neuropathy, clotting of conventional hemodialyzers and reduction of dialysis time and frequency. The outcome was beneficial in all cases and stable biochemical and hematological parameters were maintained. No increase in heparin requirements was noted and the therapy was thought to be cost-effective.

Hemoperfusion in Reduced-Time Programmes for Chronic Uremia. Long-Term Results

This paper reports the Authors' 8 year experience in the clinical use of charcoal hemoperfusion as a means to reduce the weekly time of treatment in chronic uremic patients. Two different programmes were applied. Programme A (34 patients) which involved substituting the 3 procedures per week of standard dialysis (4 hours duration each) by 2 procedures of combined hemodialysis and hemoperfusion, again of 4 hours duration each. Programme B (18 patients) which involved substituting the 3 procedures per week of 4 hours duration by 3 procedures of 3 hours each, 2 of combined hemodialysis and hemoperfusion, 1 of conventional dialysis. The net weekly reduction was 33% for Programme A and 25% for Programme B. The efficacy of the two Programmes was evaluated by clinical, hematochemical, nutritional and instrumental parameters.

The optimal timing of hemoperfusion component in combined hemodialysis-hemoperfusion treatment for uremic toxins removal

The combination of hemodialysis-hemoperfusion (HDHP) has been proved to be superior to hemodialysis (HD) in eliminating uremic toxins. There are two methods of combination of HD and HP: the HP regime is utilized during the first two-hour an early HP conducted HDHP (EHDHP) or the last two-hour late HP conducted HDHP (LHDHP) of 4 h regular HD session. The present study was to compare these two methods in uremic toxins removal. Twenty adult chronic HD patients were enrolled in this self-control method study. The patients were randomized to receive one session of EHDHP or LHDHP. Two weeks later, the dialysis modalities were switched. The reduction ratio (RR) of targeted uremic toxins for each session was assessed. Both EHDHP and LHDHP showed a significant removal of small water-soluble solutes, middle-sized toxins and cytokines as well (p < 0.05). There were no significant differences between two methods in RR of small water-soluble solutes, like urea and creatinine. For middle-sized molecules and cytokines, such as PTH, β(2)-M, IL-1, IL-6, and TNF-α, the RR was markedly increased in LHDHP than that in EHDHP (p < 0.05). LHDHP showed no more intradialytic events than EHDHP. The combination of HD and HP in the last two hours in one hemodialysis session had more effect on eliminating middle-sized toxins and cytokines.

Performance characteristics of combined haemodialysis/haemoperfusion system for removal of blood toxins

The application of high clearance haemodialysis (HD) for removal of small molecules of waste metabolites, has been practised for many years. Haemoperfusion (HP) is capable of effective removal of middle and protein-bound molecules. The combined HD/HP system is thought to give a more effective treatment for patients of renal failure or drug intoxication. This paper discusses the performance characteristics of removal of toxic substances (e.g. paraquat and creatinine), using the combined HD/HP recycled system in two different arrangements (HD-HP and HP-HD). The results demonstrate that for most favourable adsorbing solutes, the HD-HP arrangement gives higher performance whereas, HP-HD arrangement is more suitable and gives more effective detoxication characteristics for unfavourable adsorbing solutes.

Artificial cells in immobilization biotechnology

Artificial cells contain biologically active materials. Artificial cells containing adsorbents have been a routine form of treatment in hemoperfusion for patients. This includes acute poisoning, high blood aluminum and iron, and supplement to dialysis in kidney failure. Artificial cells are being tested for use as red blood cell substitutes. Artificial cells encapsulated cell culture are being tested in animals for the treatment of diabetes and liver failure. A novel 2 step method has prevented xenograft rejection. Artificial cells containing enzymes are being studied for treatment in hereditary enzyme deficiency diseases and other diseases. Recent demonstration of extensive enterorecirculation of amino acids in the intestine has allowed its oral administration to deplete specific amino acids. Artificial cells containing complex enzyme system convert wastes like urea and ammonia into essential amino acids. Artificial cell is being used for the production of monoclonal antibodies, interferons and other biotechnological products. It is also being investigated for drug delivery, and for use in other applications in biotechnology, chemical engineering and medicine.

Glucose Metabolism, Lipidic Pattern, Apolipoprotein A and B during Hemodialysis with Cuprophan and Hemodialysis-Hemoperfusion

We studied differences in the glucose metabolism, lipid pattern and apolipoprotein A and B after one month of combined hemodialysis-hemoperfusion (HD-HP) in eight regular maintenance hemodialysis (HD) patients.

After one month of HD-HP predialytic serum creatinine and phosphate were lower than during the preceding HD period; the lipidic pattern and apolipoproteins were unchanged. A single HD-HP session significantly reduced triglycerides; this does not occur during HD. Postdialytic changes of all other lipoprotein metabolism parameters are identical in the two techniques.

As regards glucose metabolism, after one month of regular HD-HP treatment glycemic curves during the intravenous glucose tolerance test (IVGTT) were perfectly matched with those in HD. However, insulin production was lower, with a reduction of the insulin resistance index. Differences did not reach statistical significance.

The Authors infer that activated charcoal, even though it achieves better blood purification in uremia, may be unable to remove specific substances which hamper some key enzyme activities of the carbohydrate and lipid metabolism.