EFFETTI DELLE DIFFERENTI SOLUZIONI DI REINFUSIONE SULLA CINETICA DEL CALCIO IN CORSO DI PAIRED FILTRATION DIALYSIS (PFD)

PFD is an effective blood treatment resulting from the coupling of hemofiltration and dialysis in two separated devices, a polysulfone (P) and a hemophan (H) filter, respectively. The aim of this study was to evaluate calcium (Ca) kinetics during PFD with three different reinfusion solutions: a) saline (0.9% NaCl), b) bicarbonate (HCO ₃ 40 mmol/l) and c) calcium lactate (Ca ⁺⁺ 4 mmol/l). Dialysate calcium concentration was 1.75 mmol/l; ultrafiltration flow rate was 50 ml/min. The studies were performed by collecting simultaneously three blood samples: at P inlet, between P and H and at H outlet to measure total and ionized calcium concentrations. The driving force was also calculated (as the difference between the calcium ionized concentration in the inlet dialysate and its blood concentration) in each dialysis session. Calcium fluxes (mg/min) through P (as convective loss) and H (as diffusive uptake) were separately calculated by using total calcium concentrations. The results have shown a positive calcium kinetics only with a reinfusion containing calcium lactate although both the driving force and the diffusive uptake were greatly reduced with this kind of reinfusion.