Femoral nerve block is an effective analgesic mode in patients after total knee arthroplasty. In recent studies, there has been shown that a large amount of neutrophil elastase release from neutrophils could induce the development of deep venous thromboembolism and femoral nerve block may reduce the incidence of the development of deep venous thromboembolism. In addition, inflammatory cytokines including interleukin-1(IL-1), IL-6, IL-8 and tumor necrosis factor(TNF) were associated with deep venous thromboembolism. Thus, the investigators hypothesised that preemptive analgesic of femoral nerve block could prevent deep venous thromboembolism due to inhibiting the excessive release of neutrophil elastase and inflammatory cytokines.
To investigate whether preemptive analgesic of femoral nerve block could prevent deep venous thromboembolism due to inhibiting the excessive release of neutrophil elastase and inflammatory cytokines.