Thermal sensor and on-line hemodiafiltration
Cogliati, P.
Giornale Italiano di Nefrologia Organo Ufficiale Della Societa Italiana di Nefrologia 22(Suppl 31): S111-S116
2005
ISSN/ISBN: 0393-5590 PMID: 15786382 Document Number: 589232
Among the advantages of hemodiafiltration (HDF) cardiovascular stability seems the most popular. For several years the theory was that fluid infusion at a lower temperature induced similar effects to 'cool dialysis'. Due to the studies of Maggiore in 1982, we know that hemodialytic treatment per se induces in the majority of patients a rise in body temperature, on average 1.5-2 degrees C; the reasons for this phenomenon are unclear, even if theories developed in different trials take the following deputed to body cooling into account; an increase of the catabolism, linked to the bioincompatibility of the materials or to pyrogenic and cytokine-inducing substances, or a reduction in thermal scattering by the vasoconstriction of vasular districts such as skin and muscles. A device has been developed, the BTM (R) , which is able to measure the blood temperature at the arterial and venous side of the extracorporeal line and to modify the dialysate temperature, thereby inducing an analogous variation of the venous blood temperature. Therefore, we were able to precisely calculate the thermal balance during the dialytic treatment and work automatically to ensure sessions in which the body temperature remained stable, continuously (isothermic dialysis), or to observe that the thermal balance could vary during the same session (thermoneutral dialysis). Several multicentric studies, carried out in Europe, and particularly in Italy, have demonstrated that isothermic dialysis reduces the number of dialytic sessions complicated by symptomatic hypotension by 50%, particularly in hypotension prone patients.