2. Materials and methods
heart disease, phlebitis, osteoarthritis, allergy, anemia, vascular lesion, DVT, systemic rheumatic diseases, coagulopathy, liver/kidney failure, diabetes
RHEUMATOID ARTHRITIS, PULMONARY EMBOLISM, RECRUITMENT, GROUP B, HEART DISEASE, PHLEBITIS, OSTEOARTHRITIS, ALLERGY, SYSTEMIC LUPUS ERYTHEMATOSUS, DVT, ANEMIA, COAGULOPATHY, COLD, ANKYLOSING SPONDYLITIS, DIABETES
This prospective, double-blind, randomized, controlled study was conducted from February 2017 to July 2022. Recruitment was approved by the institutional review board and registered at the Chinese Clinical Trial Registry (ChiCTR2300071161). All patients provided written informed consent before participation. Inclusion criteria were unilateral TKA for osteoarthritis and a signed informed consent form. Exclusion criteria were as follows: allergy for TXA and cold; age ≤ 50 years or ≥80 years; active phlebitis and diabetes with vascular lesion; glucocorticoid use within 3 months or any strong opioids and anticoagulants within a week; history of severe heart disease (NYHA > 2), liver/kidney failure, or systemic rheumatic diseases (rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus); DVT, pulmonary embolism, and coagulopathy before surgery; prior ipsilateral knee surgery; lack of cognitive function or normal sensation; preoperative anemia; and loss to follow-up.The 200 patients were randomly divided into 4 groups (A, B, C, and D), each with 50 patients. All patients were randomly assigned sequences hidden in opaque, sealed envelopes that were opened before surgery. All patients receive intravenous TXA (1 g, 100 mL normal saline, NS) 30 minutes before releasing tourniquet and the drainage was clamped for the first 4 hours after operation. Patients in Group A received an intra-articular injection of NS (10 mL) by drainage and then clamped. Patients in Group B received an intra-articular injection of TXA (1 g, 10 mL NS) by drainage and then clamped. Patients in Group C received an intra-articular injection of NS (10 mL) by drainage and then clamped and continuous cryotherapy postoperatively. Patients in Group D received an intra-articular injection of TXA (1 g, 10 mL NS) by drainage and then clamped and continuous cryotherapy postoperatively. The continuous cold flow device adopted was Evercryo (China). Cryotherapy continues to perform 90 minutes per 120 minutes until 7 days after surgery and ice was changed in the canisters every 4 hours by the nursing staff. All participants, surgeons, anesthesiologists, nurses, and research assistants were blinded to group allocation.