Abstract
Background
Revision total knee arthroplasty (rTKA) is a complex procedure with increased risk of blood loss and transfusions. The Musculoskeletal Infection Society has included D-dimer as a serology marker for peri-prosthetic infection. The study's intent is to understand the impact of preoperative D-dimer levels on blood loss and venous thromboembolism in revision TKA.
Methods
Following IRB approval, rTKA performed by a single surgeon between January 1, 2017 and December 31, 2019 were reviewed. Inclusion criteria consisted of pre-operative D-Dimer, cemented revision TKA of one or both components under tourniquet control. 89 patients met the criteria including 37 males (41.6%) and 52 females (58.4%). Mean ages were 65 for males and 67 for females. The data revealed 54 patients (61%) had an elevated D-dimer (group 1) and 35 patients (39%) had a normal D-dimer (group 2). Sex stratification showed 21 males (57.8%) and 33 females (63.5%) with elevated D-dimer. TXA protocol included 2 grams intravenous (82 patients) or 2 grams intra-articular application (7 patients). Post-operative anticoagulation included Lovenox 40mg daily for 2 weeks followed by aspirin 325 twice daily for 4 weeks. Pre-operative and post-operative hemoglobin, transfusion rates and post-operative VTE within 90 days of surgery were recorded.
Results
The mean pre-operative hemoglobin (hgb) was 13.30 and post-operative was 11.21. The mean change in hgb for males was 2.75 and for females 1.91. Both male and female cohorts had an acceptable range and the change in hgb was not statistically significant (p=0.076). Two female patients (2.25%) were transfused, both receiving IV TXA and their pre-operative hgb was lower than the cohort. No VTE events were identified in either groups of patients within the 90 day post-operative period.
Conclusion
This study revealed that TXA is effective in reducing blood loss following rTKA and an elevated D-dimer is not a contraindication to its use.
