Anemia before reimplantation surgery : An overlooked modifiable risk factor of septic revision knee arthroplasty failure
Preoperative anemia in patients undergoing a two-stage septic revision arthroplasty may be a
factor of reinfection, even in the presence of aggressive antimicrobial therapy. Patient Blood Management (PBM) in
such patients is challenging. We evaluate the impact of anemia existing before re-implantation on a failure rate after
two-stage septic total knee arthroplasty (rTKA), and explore feasibility of a PBM strategy implementation in these
Materials and methods:
A retrospective study of patients from January 2010 to January 2015 in a French
regional referral center was performed. Patients undergoing a two-stage rTKA for infection after successful primary
TKA were identified and followed up to 31.12.2018. The primary outcome (failure) was defined as surgical site
infection after re-implantation requiring new surgery. The secondary outcomes were time to failure, the time between
explantation/reimplantation, transfusion rate during the second stage. Preoperative anemia was defined as Hb
level < 12 g/L before the re-implantation.
69 patients were identified; 17 (24%) developed reinfection of rTKA
in 105 [11.4–156] days. In these patients pre-implantation anemia was more frequent (n = 13(76.5%) in failed vs.
n = 21(40%) in non-failed, p = 0.0110). During the explantation stage, there were no significant group differences
in age, sex, comorbidity, type of spacer and antimicrobial therapy, iron supplementation, or transfusion rate. The
median time between explantation/reimplantation surgery was 51 [43–71.5] days, indifferent between the two groups.
Intraoperative transfusion during reimplantation was required in 12 (17%) patients, more frequent in failed patients.
None of the patients had contraindications for the PBM strategy except the cell-saver use.
In two-stageseptic rTKA preoperative anemia was almost two times more frequent and associated with an elevated rate of septic
failure. The time-frame between explantation and-re-implantation is sufficient to implement a PBM strategy for all
anemic patients. Before-after studies would be of interest to determine the best PBM strategy to prevent anemiaassociated
septic failure in such a condition.