Impact of tourniquet during knee arthroplasty: a bayesian network meta-analysis of peri-operative outcomes.

INTRODUCTION: The role of tourniquet during knee arthroplasty is controversial. The present study compares various tourniquet protocols using a Bayesian network meta-analysis of peri-operative data. MATERIAL AND METHODS: The present study was conducted in accordance with the PRISMA extension statement for reporting systematic reviews incorporating network meta-analyses of health interventions. The literature search was conducted in September 2020. All clinical trials investigating the role of tourniquet in knee arthroplasty were considered for inclusion. Methodological quality was assessed using Review Manager 5.3. A Bayesian hierarchical random-effects model analysis was used in all comparisons. RESULTS: Ultimately, pooled data from 68 studies (7413 procedures) were analysed. Significant inconsistency was found in the data relating to total estimated blood lost; no assumption could be made on this outcome. Full-time tourniquet resulted in the shortest surgical duration and lowest intra-operative blood lost, in both cases followed by incision-to-suture. The incision-to-suture protocol achieved the smallest drop in haemoglobin during the first 72 h post-operatively and the lowest rate of blood transfusion, both followed by full-time tourniquet. Hospitalisation was shortest in the absence (no-tourniquet) group, followed by the cementation-to-end group. CONCLUSION: For knee arthroplasty, longer tourniquet use is associated with the shorter duration of surgery, lower intra-operative blood lost, lower drops in haemoglobin and fewer transfusion units. The shortest average hospitalisation was associated with no tourniquet use.