Continuous Veno-Venous High Cut-Off Hemodialysis Compared to Continuous Veno-Venous Hemodiafiltration in Intensive Care Unit Acute Kidney Injury Patients

Abstract

Aims: High cut-off (HCO) continuous veno-venous hemodialysis (CVVHD) was compared to high-flux membrane (HFM) continuous veno-venous hemodiafiltration (CVVHDF) in intensive care unit (ICU) acute kidney injury (AKI) in terms of efficiency, hemodynamic tolerance, medium-sized molecules removal, albumin loss, and inflammatory system activation. Methods: In a prospective cross-over randomized study, 10 AKI patients underwent successively HCO (Ultraflux EmiC₂: β₂-microglobulin [β₂M] sieving coefficient [SC]: 0.9) CVVHD and HFM (Ultraflux AV1000S: β₂M SC: 0.65) ­CVVHDF. Results: Over the 20 sessions, hypotensive and febrile episodes, reduction rates of urea, creatinine, and β₂M were similar in both modalities. Though dialysis dose was higher with CVVHDF (36 ± 4 vs. 21 ± 6 mL/Kg/h), urea, creatinine, and β₂M instantaneous and plasmatic clearances did not differ except for urea at 12 h. Protein loss, superoxide anion production, cytokines, and growth factors variations were also comparable. Conclusion: HCO CVVHD is well tolerated and is as effective as HFM CVVHDF in clearance of solutes and removal of β₂M. It induces neither protein loss nor overproduction of superoxide anion. Video Journal Club “Cappuccino with Claudio Ronco” at http://www.karger.com/?doi=489082.

Clearance of Inflammatory Cytokines in Patients with Septic Acute Kidney Injury During Renal Replacement Therapy Using the EMiC2 Filter (Clic-AKI Study)

“…We noted a small degree of adsorption of IL-2 and VEGF which contributed to total mass removal. However, "negative adsorption" was also observed for all cytokines consistent with similar reports in the literature [9,22,24]. The mechanisms for this "desorption" phenomenon are unclear and might be explained by effects of hemoconcentration on the outflow side (which we corrected for in our study), release of previously bound cytokines [39], activation of the inflammatory system through reverse diffusion [22], cytokine induction from dialyzer bio-incompatibility [40], activation or deactivation by enzymes after sampling, or sampling errors.…”

“…Previous studies explored cytokine changes and cytokine removal by the EMiC2 filter, but none have fully investigated the various mechanisms of cytokine clearance in critically ill patients with sepsis [19][20][21][22]. Despite reported decent removal of IL-6, IL-8, IL-1β, and TNF-α (MW 8.4 to 25 kDa) in-vitro, the effluent clearance rates varied markedly in humans [20,21,37].…”

“…Other studies reported higher removal of kappa light chains (23kDa), β2microglobulin (17kDa), myoglobin (17kDa), IL-6, and IL-8 in patients receiving treatment with EMiC2 filters compared with standard high-flux membranes [18][19][20][21]. Continuous veno-venous hemodialysis (CVVHD) using the EMiC2 filter was well tolerated and albumin loss was limited [22].…”

“…Furthermore, the causal link between reduction of plasma cytokine concentration and extracorporeal cytokine removal has not been demonstrated [20,22]. Before proceeding to a trial comparing the EMiC2 filter with other commercially available filters to manage sepsis-associated AKI, it is important to determine the characteristics and the actual magnitude of cytokine removal in vivo.…”

The Efficacy of Continuous Venovenous Hemodiafiltration with Cytokine Filter on Sepsis

“…In the study by Balgobin et al in patients with ARF at the ICU comparing continuous venovenous high flux (EMIC-2) hemodialysis and CVVHDF, they approved that there is no significant difference between the levels measured before and after the CVVHDF of the proinflammatory cytokines (TNF-α, IL-1α, IL-1β, IL-2, IL-6, and IL-8) and anti-inflammatory cytokines (IL-4 and IL-1β) (27). In our study, changes between the levels of IL-1β and IL-6 were not significantly measured before and after the CVVHDF using two different filters comparing two groups and values in each group.…”