Electric cautery does not reduce blood loss in primary total knee arthroplasty compared with scalpel only surgery a double-blinded randomized controlled trial

Purpose The purpose of this study was to systematically compare blood loss between the electric cautery and scalpel used in primary total knee arthroplasty (TKA). Methods We performed a double-blind trial randomizing osteoarthritic knee patients undergoing unilateral TKA done by either using scalpel (group S) or cautery (group C). Primary outcomes were total blood loss calculated from maximum haemoglobin drop and blood loss collected in drain. Secondary outcomes were systemic inflammatory response (serum C-reactive protein), wound complications, and functional outcomes assessed over three months. Results A total of 80 patients were recruited. Group S had similar calculated total blood loss compared to group C (1070 (S) vs 1128 (C) mL, 95% CI -219 to 103, p = 0.47). There was no difference in the mean drain-collected blood loss between the two groups (443 (S) vs 486 (C) mL, 95% CI -128 to 47, p = 0.36). Group C had higher serum C-reactive protein level at 48 hours after TKA compare to group S (105 vs 140 mg/dL, 95% CI - 66 to -4, p = 0.03). Wound complications and functional outcomes at three months were also similar between the two groups. Conclusions Using electric cautery does not reduce total blood loss as we thought it would be in primary TKA compare to scalpel only surgery and it is also associated with a greater systemic inflammatory response. Cautery used in TKA which operated under tourniquet may not be worthwhile for the risk of hazardous smoke and the increasing cost.