Reduced Capacity of Whole Blood Leucocytes to Express Tumour Necrosis Factor-α and Interleukin-10 following Major Orthopaedic Surgery

Abstract

Background: Severe trauma is a challenge to the immune response and may cause reduced immune capacity. As a marker of decreased cellular activity, studies with ex vivo lipopolysaccharide (LPS) stimulation of whole blood or isolated mononuclear cells from injured patients have revealed reduced production of inflammatory cytokines. To gain further insight into immune alterations in orthopaedic surgery, we studied LPS-induced tumour necrosis factor (TNF)-α and interleukin (IL)-10 in whole blood of patients during peri- and postoperative phases of total hip replacement. Methods: Four females and 3 males undergoing elective total hip replacement were included in the study. Ex vivo LPS-induced TNF-α and IL-10 were measured in a whole blood assay before, during and at 1 and 6 days after operation. In addition, the counts of white blood cells were determined. Results: During the operation, there were significant reductions in the number of monocytes, but at day 1 and 6 after surgery, there were significant increases as compared to the levels before surgery. The capacity of whole blood to express TNF-α and IL-10 did not change significantly during the operation and the following postoperative day. At day 6, however, there were significant reductions in expression of both TNF-α and IL-10 as compared to the levels before the operation. In relation to the values of monocytes, there was a significant reduction in the expression of TNF-α also at day 1 after operation. Conclusion: Our data indicate that in the course of at least 6 days after a major orthopaedic trauma, there is suppression of the whole blood capacity to express the inflammatory cytokine TNF-α and the anti-inflammatory cytokine IL-10 when exposed to LPS. During this time, then, the patient is particular susceptible to septic complications.