Effects of Tourniquet Use during Total Knee Arthroplasty on Global Cytokine Changes Associated with Ischemia Reperfusion Injury

Abstract

PURPOSE: The use of tourniquets during total knee arthroplasties (TKA) has been debated given the possibility that prolonged application of a tourniquet may result in ischemia-reperfusion injury (IRI), potentially contributing to post-operative muscle atrophy. The goal of this study was to elucidate the influence that tourniquet use may have on the induction of IRI in muscle tissue following TKA surgeries. We hypothesized that tourniquet use during TKA causes larger global increases in pro-inflammatory cytokines, indicating the occurrence of IRI. METHODS: 50 patients undergoing TKA surgeries were separated into 3 groups: no tourniquet (NoT; n=17), operative tourniquet (OT; n=15), and tourniquet during implant cementation (TDC; n=18). Induction of IRI was evaluated by measuring changes in fifteen cytokines present in blood samples collected from an antecubital vein immediately before and after surgery. Pre- to post- surgery changes in cytokine concentrations were compared between groups. RESULTS: Compared to immediately before surgery, cytokine levels generally decreased after surgery in the NoT and OT groups, but increased in the TDC group. Despite these differences, pre- to post- operation changes in IL-1β, IL-10, IFNY, IL-4, IL-5, IL-7, IL-8, Eotaxin, IP-10, MCP-1, MIP-1α, MIP-1β, RANTES, and TNFα concentrations were not significantly different between groups. However, significant differences were found for IL-12, a pro-inflammatory cytokine (p=0.01). After surgery, IL-12 concentrations decreased in the NoT (pre: 72.8 ± 89.8 pg/mL, post: 41.3 ± 28.6 pg/mL) and OT (pre: 92.1 ± 142.2 pg/mL, post: 82.9 ± 167.4 pg/mL) groups, and increased in the TDC group (pre: 52.0 ± 85.1 pg/mL, post: 63.0 ± 116.7 pg/mL). However, Cohen’s d effect sizes between groups were small (NoT vs OT = 0.08; NoT vs TDC = 0.12; OT vs TDC = 0.18). CONCLUSIONS: Using global changes in pro-inflammatory cytokine levels as an indicator of IRI, these data suggest that the use of a tourniquet does not significantly contribute to induction of IRI in TKA surgeries. However, additional studies comparing local plasma cytokine changes near the tourniquet site and utilizing larger sample sizes are necessary to determine if tourniquets should be used in TKA without inducing IRI.