Silicone ring tourniquet versus pneumatic cuff tourniquet in total knee arthroplasty surgery: A randomised comparative study.

Introduction: The aim of the present study was to compare a silicone ring tourniquet (SRT) and a classic pneumatic cuff tourniquet (PT) in patients undergoing total knee replacement. We have compared the impact on the glycolytic activity caused by the ischaemia applied to the limb during the surgery.

Material and methods: 140 patients that underwent total knee arthroplasty (TKA) were randomised in two groups. Serum lactate determination was made by reactive strips of enzymatic-amperometric detection, 5 min before tourniquet application and 5 min after tourniquet removal.

Results: The mean tourniquet time was similar for both groups (p 0.13). Postoperative serum lactate levels were higher with statistical significance than the preoperative levels and with a positive Pearson´s correlation in the overall cases. The postoperative serum lactate levels where higher in the PT group (4.097 ± 2.248 mmol/L) than the SRT group (3.499 ± 1.566 mmol/L). There was no significant difference (p 0.07) to be able to affirm that there was a difference of the anaerobic metabolism according to the tourniquet system used.

Discussion: Ischaemia applied to the lower extremity during knee replacement surgery can produce tissue injury. Serum lactate determination allows comparison of the ischaemic changes during TKA surgery caused by two different tourniquet systems.

Conclusions: SRT may be not disadvantageous compared to the classic PT from the impact on the glycolytic activity caused by the ischaemia.Level of evidence II.