what is the differences in complications of Isolated UF and Hemodialysis ?
Isolated ultrafiltration (no dialysate) is hemodinamically better tollerated, that is less complications. This is because the blood has lower temperature, there is no electrolyte shift. Moreovere osmolarity increases. There is not CO2 from dialysate. At any rate bun and K increase !!
Electrolytes, as well as, BUN and so other, pass the membrane by mean of convetion (Solvent Drug) not by diffusion. It should be stressed that water mainly passes indeed electrolyte concentration increases
It depends what is the reason for the extracorporeal therapy you want to apply - just removal of excess fluid (e.g. because of heart congestion) or should some catabolites be removed too and there is just not sufficient tolerance to fluid removal. With the former reason isolated UF is fine. For the latter you may either use isolated UF followed by conventional haemodialysis with very little or no ultrafiltration at all or you can try to run dialysis at lowered dialysate temperature and/or use a decreasing ultrafiltration rate. Both the lowered temperature and the profiled UFR should result in increased tolerance to UF.
I have done both isolated UF (no dialysis) and Sequential UF (to get rid of excess fluid followed by stabdard but shorter duration hemodialysis). the choice depends on the patient.. Is it volume excess that is urgent issue in a hemodynamically unstable patient (with poor systolic function) and K or HcCO3 or Ca are not priorities then isolated UF is probably a better way to fo. However I do not think there is any RCT data in the literature that says a particular approach is better
Isolated UF is better tolerated in unstable patients that with fluid overload. It can be used to remove more volume in less time. In emergent patients, I have been able to remove 1.5 Kg per hour without complications.As already mentioned, it is dangerous patients with hyperkalemia because the concentration of serum potassium increases with UF. Also, isolated UF does not remove solutes adequately and does not replace dialysis in patients with renal failure. In these patients, to achieve dialysis adequacy the duration of dialysis should be kept without discounting UF time.
each of method has its indications and benefits .
i mean in iso UF is there any passage of electrolytes through membrane ?
if no ........ , do you use the same kind dialyzer in iso UF as in dialysis ?
@Marco Marano, Electrolytes, as well as, BUN and so other, pass the membrane by mean of convection (Solvent Drug) not by diffusion but solutes concentration would not be increased
Extracorporeal dialysis treatments based on isolated ultrafiltration with reinfusion of the exceeding filtrated mass versus a predefined amount of water loss, are generally characterized by a quite better tolerance of dialysis procedure as well as better general conditions.Theoretically this procedures should be preferred versus the standard hemodialysis treatments, but this is impossible for the high cost of hemofiltration. Therefore this therapy is used for persons undergoing dangerous hypotensive episodes with standards treatments, particularly in case of aged subjects. The bases of the better obtained conditions were very clearly exposed in previous replies. The cardiovascular stability offered by isolated ultrafiltration very usefully can be used on subjects undergoing a decompensation episode.in course of a chronic cardiac insufficiency: In these cases also a treatment based on a peritoneal dialysis seance using hypertonic solutions can attain very satisfying results as I had occasion to verify in many occasions .
dear Giancario
thanks for reply . I mean only isolated UF without replacement fluid .
Dear Ramin, I am afraid to have inadequately exposed the different aspects of treatments based on UF. In case of dialysis treatment , this method to attain an adequate level of solutes removal has to ultrafiltrate a volume/minute of fluids widely greater than the simple amount of fluid needed to restore the correct dry weight of the patient consequently it is mandatory to continuously replace the fluid removed in excess. Differently, the use of isolated UF is restricted only to the cases in which the fluid removal is necessary to treat a dangerous body water overcharge, in patients with decompensated cardiac insufficiency or in heavy over hydrated ESRD patients, inadequately responders to diuretics given intravenously in high dose, or in case of dialysis patients in conditions of acute heavy over hydration. I like to remind that in case of decompensated cardiac insufficiency as well as in case of over hydrated ESRD patients, successful results can be achieved also by peritoneal dialysis, very well tolerated by these patients.