Kinetics of TNF-α during continuous hemodiafiltration in patients with sepsis

Methods of renal replacement therapy due to the capability to eliminate products of cytolysis are now widely used for correction of generalized inflammation. An additional influence on the detoxication process has an adsorption component of anti-inflammatory mediators on the hemodiafilter membrane.

Materials

Nineteen patients (nine male/10 female) 15–73 years of age with sepsis who received continuous hemodiafiltration (CHDF) treatment were examined. The APACHE II score was 28.3 ± 0.4. Fifteen patients underwent mechanical lung ventilation, and 13 had inotropic support. The mortality rate was 43.9%. Hemoprocessor 'Prisma' kits with membrane AN69 and solutions from 'Hospal' Company (France) were used for CHDF. The mean duration of CHDF was 73.8 ± 7.0 hours with the filtration volume of 80.4 ± 1.6 l/day.

Results

Concentration of TNF-α during CHDF were 386.3 ± 111.6–429.3 ± 80.7 pg/ml. A significant amount of this cytokine was measured in all effluent samples (90.9–132.5 pg/ml). Daily TNF-α elimination was 8.92 ± 0.94 μg. Clearance was 80.2 ± 6.3 l/day, which was one-third of the blood volume that has been perfused through the hemodiafilter. We found a correlation between the volume of effluent and TNF-α elimination (r = +0.49 ± 0.04; n = 30; P < 0.05). The difference between TNF-α content in the plasma volume before and after hemodiafilter, at a mean blood speed of 150 ml/min, hematocrit of 26.7% and plasma flow of 110 ml/min, was 17,160 pg/min. At the CHDF speed of 55.6 ml/min, 6183 pg/min TNF-α was eliminated. The difference between TNF-α content in plasma and effluent volume was 10,977 pg/min, which acknowledges the receipt of significant absorption of this cytokine on the hemodiafilter membrane during the first 6 hours of the CHDF procedure.

Conclusion

Significant amounts of TNF-α can be eliminated using CHDF filtration and absorption, which is important in the absence of natural hepatorenal clearance during multiple organ failure.