Peritoneal dialysis appears to be a promising therapeutic tool for patients affected by refractory CHF. Clinical improvement of cardiac function may be related to clearing blood from middle molecular weight myocardial depressant substances, including atrial natriuretic peptide. Prospective multicentre trials are needed to confirm these encouraging results.

This prospective study was designed to evaluate the eventual correction of anemia and iron status in 39 iron-deficient uremics starting hemodialysis. Nine patients (control group) had no iron supplementation, 10 had oral ferrous iron, and 20 were treated with intravenous iron gluconate. Follow-up periods were 12 months for the control group and 26 months for patients treated with oral or intravenous iron. No patient was treated with erythropoietin. At zero time, all patients were anemic (Hb <78 g/l) and showed signs of severe iron deficiency, diagnosed on the basis of depleted bone marrow iron stores, reduced hemoglobin iron, and transferrin saturation <21%. The hemoglobin levels, observed in patients of the control and the oral iron groups at the end of the follow-up periods, were not significantly different from those detected at zero time. In contradistinction, patients treated with intravenous iron showed after 26 months of follow-up a significant increase of blood hemoglobin values, reaching a mean value of 126 g/l. So far, this evidence supports both the concept that iron absorption is compromised in chronic uremics and that the parenteral way is the more effective route for iron replacement in this specific group of patients.

We present a direct link between the neutralization of anionic sites by intraperitoneal protamine and a rise in protein passage to the peritoneal cavity during isosmotic peritoneal dialysis in rabbits. Each experiment included two 1-hour exchanges. No drugs were added in the first exchange. In group A (control) there were no drugs in the second hour either. In group B, protamine (50 μg/ml) was added to the second exchange volume. In group C, protamine and heparin (50 U/ml) were added. In groups A and C, appearance curves of metabolites during the first (baseline) and the second (experimental) hours were not statistically different. In group B, differences for urea, glucose and uric acid were not significant, but they were highly so for protein (increase of 100%, p < 0.01). Transperitoneal passage of albumin is substantially enhanced by protamine. Neutralization of protamine with heparin prevents this, showing that availability of anionic sites is the crucial limiting factor. Protamine did not significantly affect the transfer of small neutral molecules.

Mortality observed in this retrospective, uncontrolled study was significantly lower than that currently observed with conventional supportive therapy, with or without the addition of other forms of blood purification, e.g. CAVH and CAVHD. This improvement in results appears to be related to the property of SH to completely clear 90% of the blood from mediators of inflammation in only one passage through the hemofilter, and to better tolerance of HD done using bicarbonate buffer. A definite evaluation of this technique will be eventually reached by a programmed, appropriate sample size study, which is out of reach for one individual ICU.

Automated peritoneal dialysis appears as a promising tool for treating patients suffering from refractory, end stage congestive heart failure. Improvement of cardiac function may result from clearing the blood from middle molecular weight myocardial depressant substances, including atrial natriuretic peptide. Results of this investigation are a call for a prospective multicenter study in order to confirm these promising observations.