[Experience with inline intermittent hemodiafiltration as renal replacement therapy in critically ill patients]

In critical patients with acute renal failure, intermittent diffusive renal replacement techniques cause hemodynamic problems due to their high depurative efficiency. This situation is avoided using continuous low efficiency therapies, which are expensive, prevent patient mobilization and add hemorrhagic risk due to systemic anticoagulation. Intermittent and prolonged hemodiafiltration (HDF) has the depurative benefits of diffusion, plus the positive attributes of convection in a less expensive therapy.

To report our experience with intermittent and prolonged on-line HDF in critically ill patients.

During 2016, HDF therapies performed on critical patients with indication of renal replacement therapy were characterized. The hemodynamic profile was evaluated (doses of noradrenaline, blood pressure, heart rate and perfusion parameters).

Fifty-one therapies were performed in 25 critical patients, aged 58 ± 11 years (28% women), with an APACHE II score of 22.1 ±10. The average time of the therapies was 4.15 hours (range 3-8 hours), the replacement volume was 75 ± 18 mL/kg/h and ultrafiltration rate was 226 ± 207 mL/h. The mean initial, maximum and final noradrenaline doses were 0.07 ± 0.1, 0.13 ±0.18 and 0.09 ±0.16 μg/kg/min respectively. No differences between patients with low, medium and high doses of noradrenaline or dose increases during therapy, were observed. The greatest decrease in mean arterial pressure was 15.3% and the maximum increase in heart rate was 12.8%. Anticoagulation was not required in 88% of therapies.

High-volume intermittent or prolonged HDF is an effective therapy in critical patients, with good hemodynamic tolerability, lower costs and avoidance of systemic anticoagulation risks.