Background: Cytokines are significant mediators of the immune response to surgery and also play a role in parturition. The aim of the study was to investigate the impact of the anesthetic technique for cesarean section on plasma levels of cytokines IL-6 and TNF-alpha.
Methods: Thirty-five parturients scheduled for elective cesarean section were randomly assigned to general (n=18) or neuraxial (n=17) anesthesia. The general anesthesia group received thiopental 4 mg/kg, succinylcholine 1-1.5 mg/kg and 1% end-tidal concentration of sevoflurane in nitrous oxide and 50% oxygen. The neuraxial anesthesia group received intrathecal 0.5% levobupivacaine 1.8-2.2 mL and epidural fentanyl 1 microg/kg. Blood samples were taken for IL-6 and TNF-alpha immediately after positioning the parturient on the operating table, after uterine incision and before the umbilical cord clamping and 24h after surgery (T(1), T(2) and T(3) respectively).
Results: The two groups did not differ in IL-6 (P=0.15) or TNF-alpha (P=0.73) serum concentrations at any time point. In the general and neuraxial anesthesia groups, IL-6 serum concentrations were significantly higher in the third blood sample, T(3) (12.2+/-5.0 and 15.2+/-4.3 pg/mL), than in T(1) (0.41+/-0.38 and 0.29+/-0.10 pg/mL) and T(2) (0.37+/-0.47 and 0.24+/-0.05) respectively (P<0.001). Within each group, serum TNF-alpha concentrations did not differ significantly over time (P=0.44).
Conclusions: Under the present study design anesthetic technique did not affect IL-6 or TNF-alpha concentrations in parturients undergoing elective cesarean section. Serum IL-6 levels increased 24 h postoperatively independently of anesthetic technique.