Outcome measures
thrombosis, bleeding, intraoperative blood loss, blood loss, DVT, petechiae, thrombotic, blood transfusions, TKA, Bleeding
THROMBOSIS, BLEEDING, BLOOD LOSS, COMPLICATION, PETECHIAE, INTRAOPERATIVE BLOOD LOSS, BLEEDING, COMPLICATIONS, DVT
Demographic parameters including age, gender, side, and body mass index (BMI) were compared.Primary outcomes included post-treatment drainage volume and thrombotic complication rate. Post-treatment drainage volume was defined as the total amount of fluid drained from the drainage tube 24 h post-treatment (including the 24th h). The thrombotic complication rate was determined by dividing the number of patients with thrombosis in each group by the total number of patients. Patients underwent Doppler ultrasonography prior to TKA to assess the presence or absence of DVT. Moreover, patients received lower extremity arteriovenous ultrasound on days 3, 7, 30, 60 and 90 postoperatively, and DVT was defined if the results were positive. If PE-associated symptoms were found, the diagnosis of PE was confirmed by the positive results of CT pulmonary angiography (CTPA).Secondary outcomes included hematologic parameters, blood transfusion rate, TBL, intraoperative blood loss, and bleeding complication rate. Hematological parameters included pre-treatment and post-treatment hematological parameters. Of them, pre-treatment hematological parameters included Hb level, platelet count, PT, APTT, and PBV before treatment. The PBV before treatment was assessed according to the formula proposed by Nadler et al. [Post-treatment hematological parameters included Hb level, platelet count, PT and APTT on days 1, 3 and 5 after treatment. Platelet count, PT and APTT were collected from patients on days 1, 3 and 5 after treatment. As a result, there was no significant difference in platelet count, PT and APTT between the three groups. Therefore, platelet count, PT and APTT on day 3 after treatment were compared with those before treatment. The blood transfusion rate was calculated by dividing the number of patients receiving blood transfusions in each group by the total number of patients. Meanwhile, TBL was assessed according to the formula put forward by Gross et al. [Where PBV indicates patient’s blood volume, Hct pre stands for the initial preoperative hematocrit level, Hct post represents the lowest postoperative hematocrit level during hospitalization or the lowest postoperative hematocrit prior to blood transfusion, and Hct ave. indicates the average of Hct pre and Hct post. If a reinfusion or an allogenic transfusion was conducted, the volume transfused was added when calculating TBL.Intraoperative blood loss was determined by the net increase in gauze used intraoperatively plus the amount of fluid in the drainage bottle at the end of the procedure minus the amount of fluid used for flushing. Bleeding complications included bleeding from the incision, subcutaneous petechiae, and bleeding from other parts of the body.