[Pro convection: are convective therapies like hemodiafiltration and hemofiltration the future of extracorporeal blood purification?].
In recent years, the age and clinical gravity of hemodialysis patients have been steadily increasing. This unavoidable phenomenon is progressively leading Italian and European nephrologists to perform negative patient selection by treating symptomatic and/or critical cases with extracorporeal blood purification methods that decrease symptoms during sessions and result in reduced morbidity and mortality. While recent studies have failed to confirm the effectiveness of convective therapies in terms of mortality, more recently the advent of online convective therapies has enabled high fluid volume exchange, leading to improved clinical status and purification outcome. These therapies could offer a valid, perhaps even better alternative to mainly diffusive extracorporeal treatments, whether intermittent, daily or 'long and slow'. Indeed, convective therapies, especially biofiltration and/or acetate-free procedures, are able to efficiently purify the blood from molecules that have a major impact on patients' clinical-nutritional and inflammatory status, such as AGEs, myoglobin, osteocalcin, TNF-alpha, homocysteine, ADMA, complement factor D, and phosphates. Moreover, many studies have reduced the adverse effects of convection in terms of mortality: some aspects of the HEMO trial, the DOPPS study and many other European studies have been reassessed. Convective therapies in Europe and Italy differ from the high-flux methods used in the USA, where the convective component is markedly lower than that used in the European trials thanks to the possibility of performing high-infusate online exchanges at no cost. The indicators used for assessing the dialytic suitability of convective procedures should also be reassessed: urea Kt/V should be considerably downsized, and different markers could be used for more complete assessment, especially for medium- and large-molecular-weight uremic toxins, without neglecting the clinical and nutritional status of dialyzed patients. In the nephrologist's daily routine more time should be devoted to clinical assessment so that therapy can be personalized according to the needs of each patient.
Bolasco
P G
PG
Unità Operativa a struttura Territoriale di Nefrologia e Dialisi, ASL 8, Cagliari, Italy. pg.bolasco@tin.it
D005544:Forecasting; D017583:Hemodiafiltration / Q000379:methods; D006801:Humans; D006435:Renal Dialysis / Q000379:methods* / Q000639:trends