The effect of coupled haemofiltration and adsorption on inflammatory cytokines in an ex vivo model.
BACKGROUND
The objective of this study was to evaluate the ex vivo removal of cytokines with an extracorporeal circuit using coupled large-pore haemofiltration and sorbent adsorption.


METHODS
The setting for this study was a laboratory attached to the Intensive Care Unit of a tertiary hospital. Six healthy volunteers donated blood, which was incubated with endotoxin. Control blood was left at room temperature. Treatment blood was recirculated for 6 h through a closed circuit with a large-pore polysulfone haemofilter (average pore size 150 kDa) and an activated charcoal cartridge. Blood and ultrafiltrate were sampled hourly from three sites (pre-haemofilter for the circulating concentration, at cartridge inlet and cartridge outlet) to measure the concentrations of interleukins (IL)-1beta, -6, -8 and -10, and tumour necrosis factor (TNF).


RESULTS
Control cytokine concentrations remained the same or increased slightly. Most of the preformed circuit cytokines were removed, with the exception of IL-10. The average sieving coefficients were 0.61 for IL-1beta, 1.34 for IL-6, 0.30 for IL-8, and 0.56 for TNF. Average single-pass clearances were 49, 107, 24 and 45 ml/min, respectively. The cartridge adsorbed 90% of IL-1beta, 72% of IL-6, 100% of IL-8, and 7% of TNF during each pass.


CONCLUSIONS
The combination of a large-pore haemofilter and charcoal cartridge removed several cytokines efficiently under ex vivo conditions. This technique can now be tested for cytokine removal in vivo.
Cole
Louise
L
Department of Intensive Care, Austin and Repatriation Medical Centre, Heidelberg, Victoria, Australia.
Bellomo
Rinaldo
R
Davenport
Piers
P
Tipping
Peter
P
Uchino
Shigehiko
S
Tetta
Ciro
C
Ronco
Claudio
C
D000327:Adsorption; D002606:Charcoal; D016207:Cytokines / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification*; D004867:Equipment Design; D006440:Hemofiltration / Q000295:instrumentation; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification*; D008970:Molecular Weight; D009994:Osmolar Concentration
D016207:Cytokines; D018836:Inflammation Mediators; D002606:Charcoal