Tourniquet Effect on Patients Undergoing Total Knee Arthroplasty: A Single-Blind, Randomized Controlled Trial.

Background: Tourniquet is applied in Total Knee Arthroplasty (TKA) to reduce intraoperative blood loss and improve view of surgical field. However, tourniquet use in TKA is still in dispute. Some researchers find that tourniquet may lead to extra side effects such as aggravated pain and limb swelling, while others consider that tourniquet has no significant adverse impact on clinical outcomes of TKA patients. This trial is conducted to evaluate tourniquet effect on TKA patients.

Methods: A prospective, single-blind, randomized controlled trail is adopted with a sample size of 130 knees from August 2020 to February 2023. Patients undergoing TKA are randomly allocated to tourniquet group and non-tourniquet group. Outcomes including quadriceps thickness and stiffness, operation time, total blood loss, intraoperative blood loss, postoperative blood loss, transfusion rate, thigh circumference, knee and thigh VAS, D-Dimer and CRP level, knee function score, patient satisfaction, and complications are evaluated in this trial. Student's t-test, Mann-Whitney U test, Pearson's chi-square test, and Fisher's exact test are used in this study.

Results: No significant difference in demographic information and baseline outcomes were found (p > 0.05). Participants in the tourniquet group had significantly less total blood loss and intraoperative blood loss, more postoperative blood loss, and higher D-Dimer level on postoperative day 3 when compared with non-tourniquet group (p < 0.05). Other outcomes including quadriceps thickness and stiffness, operation time, postoperative blood loss, transfusion rate, thigh circumference, knee and thigh VAS, D-Dimer level on postoperative day 1, CRP level, knee function score, patient satisfaction, and complications showed no significant difference (p > 0.05).

Conclusion: Tourniquet application can effectively reduce intraoperative blood loss and total blood loss, without significant side effects. Hence, we advocate the regular use of tourniquet in primary TKA.