Perioperative changes of blood coagulability evaluated by thromboelastography (TEG) in patients undergoing total knee and total hip arthroplasty

BACKGROUND : A large number of studies have examined the incidence of thromboembolic complications after orthopedic surgery of the lower extremity. We investigated the perioperative changes of coagulability following total knee arthroplasty (TKA) or total hip arthroplasty (THA) using thromboelastography (TEG), which could comprehensively assess the coagulation and fibrinolytic system. METHODS : Thirty patients scheduled for TKA (n= 10), THA (n= 10) and other lower extremity orthopedic surgery (control, n= 10) were studied. TEG was analyzed with K-value, MA-value and coagulation index (CI) before induction of anesthesia and 24 hours after surgery. RESULTS : K-values decreased significantly after TKA and THA compared with the values before the induction of anesthesia. MA-values and CI increased significantly after TKA and THA compared with the values before the induction. There were no significant changes in K-value, MA-value and CI in the control group during the perioperative period. CONCLUSIONS : The results suggest that TKA and THA lead blood coagulation to hypercoagulable state at the early postoperative stage.