Analysis Of Risk Factors For Lower-limb Deep Vein Thrombosis Following Total Knee Arthroplasty

Background:Our country society Is slowly stepping into the aging of the population,with the rising number of aging population,the knee osteoarthritis of illness is also rising.As is currently the most effective means of treatment of knee osteoarthritis:total knee replacement(total knee arthroplasty,TKA),can improve the function of knee joint and reduce the joint pain.Lower-limb deep vein thrombosis(DVT)is the common complication of TKA.Pulmonary embolism(PE)caused by DVT is a fatal complication after TKA.Currently,there is a lack of comprehensive and systematic clinical studies on the risk factors of lower-limb DVT after TKA.Objective:1.The incidence of DVT after TKA was retrospectively studied,and independent risk factors for DVT were analyzed;2.To compare and analyze the clinical effect of using tourniquet in TKA of knee osteoarthritis and its influence on the risk of lower-limb DVT;3.To investigate the clinical effect of short-term postoperative intravenous tranexamic acid(TXA)and its influence on the risk of lower-limb DVT.Methods:1.The incidence of DVT in lower-limb during 223 patients who underwent TKA surgery in the Department of Arthritis Surgery of the Second Affiliated Hospital of Anhui Medical University from September 2017 to February 2019 was retrospectively analyzed.Several related factors to identify independent risk factors for DVT after TKA were analyzed by univariate and multivariate regression analysis.2.From April 2019 to January 2020,97 patients who underwent primary unilateral TKA in the second affiliated hospital of Anhui medical university,were divided into two groups which used tourniquet and used no tourniquet.,Tourniquet effect were analysed by comparing blood loss and postoperative pain,and the risk of lower limb DVT was studied by the related parameter of thromboelastogram(TEG).3.From March 2020 to August 2020,all patients undergoing primary unilateral TKA in our hospital were considered in prospective randomized controlled study.Included patients were randomized into three groups to receive either two doses of 15 mg/kg intravenous TXA postoperatively,at 2 and 24 hours after closing the incision(group A),or a single dose of 15 mg/kg intravenous TXA 2 hours postoperatively(group B),or placebo(group C).Blood loss and complication,and related parameters of prothrombotic state were compared among three groups.Results:1.Retrospective analysis showed that the incidence of DVT in patients with knee osteoarthritis after TKA was 17.0%,of which 68.4%were DVT with no obvious clinical symptoms;Multivariate Logistic regression analysis showed that advanced age,BMI?25 kg/m~2,diabetes mellitus,severe knee deformity,ASA grade 3,longer operative time,more intraoperative blood loss,higher postoperative plasma D-dimer level and longer bed time were independent risk factors for DVT after TKA.2.The intraoperative blood loss in the tourniquet group was significantly less than that in the non-tourniquet group,but the hidden blood loss was significantly higher than that in the non-tourniquet group(P<0.05).There was no significant difference in the perioperative total blood loss and operative time between the two groups(P>0.05).The peripheral diameter of the affected limb in the tourniquet group was higher than that in the non-tourniquet group,and the VAS score was higher than that in the non-tourniquet group on day 1,4 and 7 after surgery,with statistical significance(P<0.05).The HSS score of knee joint function in the non-tourniquet group was higher than that in the tourniquet group one week after surgery,and the difference was statistically significant(P<0.05).Various parameters of preoperative TEG had no significant difference between two groups.R and K of the tourniquet group were lower than the non-tourniquet group,?and CI were higher than it 6 hours after TKA.Then R and K of the tourniquet group were lower than the non-tourniquet group,??MA and CI were higher than it 1 day later(P<0.05).3.The mean TBL and HBL in group C were significantly higher than those in groups A or B,but no significant differences were found between groups A and B.None of the patients of three groups received blood transfusion.There were no significant differences in the levels of prothrombotic state parameters or incidence of DVT among groups.Conclusion:1.There was a high incidence of DVT after TKA,which is one of the important complications after TKA,especially the high incidence of latent DVT.For advanced age,BMI?25 kg/m~2,severe knee joint deformity,diabetes and preoperative grading ASA level 3,these patients were high-risk group of DVT after TKA,and should try to shorten the operation time,reduce intraoperative blood loss.Lower limb vascular color doppler ultrasound combined with D-dimer monitoring should be performed to reduce the risk of the occurrence of postoperative DVT.2.Although the application of tourniquet during TKA reduced intraoperative blood loss,the amount of hidden blood loss increased significantly,and the total blood loss did not decrease.But the application of tourniquet easily caused swelling and pain of the affected limb,which was not conducive to the early functional recovery of the knee joint after surgery.The application of tourniquet caused blood hypercoagulability and increases the risk of lower limb DVT,so it should be avoided in patients with combined independent risk factors of DVT.If the tourniquet is needed when the intraoperative bleeding of TKA affects the operation or the operation is not skillful,the time of using tourniquet should be shortened as far as possible,and the prevention and early detection of perioperative DVT should be done well.3.Short-term application of postoperative intravenous TXA in TKAs resulted in reduced HBL without a measured increase in the actual incidence of VTE or the potential risk of thrombosis,but administration of TXA after the first 24 hours had no significant effect.