Effect Of Tourniquet On Perioperative Blood Loss And Short-term Effectiveness In Total Knee Arthroplasty

Objective To investigate the effect of applying a tourniquet on perioperative blood loss and short-term effectiveness in primary total knee arthroplasty (TKA). Methods A total of94patients (94knees) with osteoarthritis underwent primary TKA between September2010and December2011, whose data met the inclusion criteria and were retrospectively analyzed. A tourniquet was used in51cases (group A), no tourniquet in43cases (group B). There was no significant difference in gender, age, affected side, body mass index, preoperative hemoglobin (Hb) level, range of motion (ROM),visual analogue scale (VAS), Hospital for Special Surgery (HSS) score between2groups (P>0.05). The data were compared between2groups, including hematocrit (Hct), Hb, hidden blood loss, dominant blood loss, theoretical total blood loss, the operation time, hospitalization days, increasing rate of circumference length above10cm of the knee, VAS score, ROM and HSS score. Results Four cases(7.84%) of group A and1case of group B (2.33%) received blood transfusions, showing no significant difference (x2=1.410,P=0.235). There was no significant difference in the Hb and Hct between2groups at2days after operation (P>0.05). The dominant blood loss of group A was significantly less than that of group B (P<0.05), while the hidden blood loss of group A was significantly more than that of group B (P<0.05), but there was no significant difference in theoretical total blood loss between2groups (t=0.662, P=0.510). The operation time, hospitalization days, and VAS score at3days showed no significant difference between2groups (P>0.05). The wound healed by first intention after operation, without related complication. At3days after operation, the increasing rate of circumference length above10cm of the knee in group A was significantly higher than that of group B (t=9.435, P=0.000), but no significant difference at7days (t=0.462, P=0.645). At3and5days after operation, the ROM values in group B were significantly larger than those of group A (P<0.05), but no significant difference at the7days (t=-1.279, P=0.204). The patients were all followed up12-18months (mean,14.3months). There was no significant difference in the HSS score between2groups at1year after operation (t=0.952, P=0.344).The X-ray films showed that the prosthesis was in good position, without loosening, subsidence, or osteolysis. Conclusion Application of a tourniquet in TKA increases hidden blood loss, and there is no obvious advantage in reducing transfusion rate compared with the non-tourniquet group, so it is recommended to reduce the time and pressure of the tourniquet for patients with high-risk of thrombosis.