Cytokine removal with a large pore cellulose triacetate filter: an ex vivo study.
OBJECTIVE
To test the hypothesis that hemofiltration using a new large pore cellulose triacetate hemofilter can achieve effective ultrafiltration of cytokines.


METHODS
Ex-vivo study.


METHODS
Laboratory of Intensive Care Unit in tertiary hospital.


METHODS
Six healthy volunteers.


METHODS
Blood from 6 volunteers was incubated for 4 hours with 1 mg of endotoxin and then circulated through a closed hemofiltration circuit with a large pore cellulose triacetate hemofilter (nominal cut-off point: 60 kilodaltons). Hemofiltration was conducted at 1 L/h or 6 L/h of ultrafiltrate (UF) flow at the start of extra-corporeal circulation, and after 2 and 4 hours. Samples were taken from the arterial, venous and UF sampling ports.


RESULTS
IL-Ibeta, IL-6, IL-8, IL-10, TNFalpha, and albumin were measured. Sieving coefficients (SC) above 0.6 were achieved for IL-Ibeta and IL-6 and SCs above 0.3 were achieved for IL-8 and TNF-alpha at 1 L/h. Sieving coefficients of all cytokines (except IL-10, p=0.22) were reduced when the ultrafiltration rate was increased from IL/h to 6 L/h (p<0.01), but the increase in ultrafiltration rate resulted in an overall increase in the clearance of all cytokines (p<0.001). The highest SC for albumin was 0.07 at 4 hours at 1 L/h, and fell to 0.01 at 6 L/h. The SCs for IL-8 fell at 4 hours (p<0.01), but the SCs for other cytokines did not change. No adsorption of cytokines and albumin was observed.


CONCLUSIONS
High volume hemofiltration (HVHF) using a new large pore cellulose triacetate filter achieved cytokine clearances greater than those reported with currently available hemo filters.
Uchino
S
S
Department of Intensive Care, Austin & Repatriation Medical Centre, Melbourne, Australia.
Bellomo
R
R
Goldsmith
D
D
Davenport
P
P
Cole
L
L
Baldwin
I
I
Panagiotopoulos
S
S
Tipping
F
F
Ronco
C
C
Everard
P
P
D000418:Albumins / Q000493:pharmacokinetics; D002482:Cellulose / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D016207:Cytokines / Q000276:immunology / Q000493:pharmacokinetics*; D006440:Hemofiltration / Q000295:instrumentation*; D006801:Humans; D066298:In Vitro Techniques; D007202:Indicators and Reagents / Q000627:therapeutic use*; D008567:Membranes, Artificial; D008851:Micropore Filters
D000418:Albumins; D016207:Cytokines; D007202:Indicators and Reagents; D008567:Membranes, Artificial; D002482:Cellulose; C024671:cellulose triacetate