A surgical procedure is a stressful event that triggers an inflammatory response. An exces­sive pro-inflammatory response is associated with a worse prognosis, while on the other hand an excessive anti-inflammatory response increases the probability of infection. Measurement of inflammatory parameters can therefore be very useful. In our study, the release of inf­lammatory parameters into the circulation was measured during liver surgery. The objective was to find out which parameters respond to surgical stress, so they could be used as inf­lammatory markers. Twenty-seven patients admitted for major liver surgery were included in the study. Blood samples were taken before, during and after the operation. The plasma concentrations of tumor necrosis factor α (TNF α), interleukin (IL)-1P, IL-6, IL-8, IL-10, lipopolysaccharide-binding protein (LBP), procalcitonin (PCT) and C-reactive protein (CRP) were measured. No changes in the plasma concentrations of TNF α and IL-1P were found. The concen­trations of IL-6, IL-8 and IL-10 increased (95% confidence interval) during the operation to 190.2 (110.4-327.7), 4.0 (1.8-9.2) and 11.3 (6.3-20.3) ng/L, respectively. This was followed by an increase in the concentrations of PCT, CRP and LBP on the first postoperative day; the mean values were 1.30 (0.78-2.17) μg/L, 57.3 (43.5-75.5) mg/L and 14.0 (11.0-17.8) ng/L, res­pectively. At that time, the concentration of IL-10 was already decreasing while the concentration of IL-8 was still increasing. The increase in the concentrations of PCT and CRP was associated with the elevation of IL-6 concentration during the surgical procedure. Hypo­xia in conjunction with reperfusion injuries contributed to the increase of IL-6, IL-8 and IL-10. The increase of IL-6 was associated with the duration of hypoxia. In addition to liver dama­ge, hypoxic and reperfusion damage to the intestines also significantly contributed to the elevation of inflammatory parameters. Inflammatory parameters could probably be used as markers of surgical stress. For their clinical use, the prognostic values of markers should be determined.