Role of Suction Drain after Knee Arthroplasty in the Tranexamic Acid Era: A Randomized Controlled Study

105 patients, scheduled for a primary unilateral total knee arthroplasty, with administered tranexamic acid, were randomized to receive a large drainage device, small drainage device or no drainage device. Outcomes of interest included pain scores on a Visual Analog Scale, morphine consumption, blood and drainage loss, range of motion, the New Knee Society Score (NKSS), suprapatellar and calf girth measurements, and the incidence of soakage of the drain site and surgical site dressings. Follow up was performed during inpatient stay, 2 weeks, 6 weeks, 3 months and 1 year. There were significant differences in gender distribution, as well as the proportion of patients with thyroid disorders between the three groups. Morphine consumption was significantly higher in the 6 hours post-operation in the no drain group compared to the large drain group, but was similar between the three groups at 6-24 hours and 24-48 hours. No significant differences were observed between the three groups in VAS pain scores, drain and blood loss, the incidence of soakage of both the drain site and surgical site dressing, and range of motion in flexion. At 3 months, NKSS scores were significantly different between the three groups, however at 1 year, there were no statistically significant differences.