CHANGES IN PLASMA IL-1β, TNF-α AND IL-6 AFTER TOTAL HIP REPLACEMENT SURGERY IN GENERAL OR REGIONAL ANAESTHESIA

Different anaesthetic methods influence the neuro-immuno-endocrine biologic responses to surgery and may thus possibly interfere with the postoperative course and development of complications. The neuroendocrine system is closely related to the cytokine network. In this study, the effects of general anaesthesia (n=6) and regional spinal/epidural anaesthesia (n=6) on the cytokine response (IL-1β, TNFα, IL-6) to uncemented total hip replacement surgery were evaluated. The postoperative clinical course was uneventful in every case. In both groups, only very low values of plasma IL-β were measured perioperatively, whereas plasma IL-6 increased postoperatively with peak values 4h after surgery. The changes in plasma TNF-α were not significant. No significant differences in plasma TNF-α or IL-6 were found between patients operated in general or in regional anaesthesia. This suggests minor influence of plasma cytokines on the possible beneficial effects of regional anaesthesia on the clinical course after surgery in low risk patients. There were slightly higher TNF-α and IL-6 levels after the operation and significantly lower cortisol levels during the operation in the regional anaesthesia group compared to the general anaesthesia group, giving rise to a significant inverse correlation between peak values of IL-6 and peak values of cortisol. This supports the theory that after surgery the inhibitory effect of cortisol on monocyte cytokine production overrides adrenergic stimulation.