Background

There is controversy regarding various aspects of simultaneous bilateral total knee replacement at the same surgical time (SBTKR). We found in the literature, disparity in the postoperative outcomes and complications associated with the procedure.

Objective

To analyze retrospectively the need for blood transfusion after surgery and complications associated with total knee replacement according to the type of procedure (SBTKR or unilateral).

Methods

Retrospective cohort analytical study. We included 251 patients with severe knee osteoarthritis that were divided into two groups. 124 (49%) who underwent SBTKR and 127 who were performed unilateral total knee replacement (UTKR). Demographic data, days of hospitalization, complications within the first 90 days after surgery (thromboembolic events, superficial and deep infection, stiffness, death); and percentages of patients transfused with blood products during hospitalization were evaluated.

Results

There were no statistical differences in the analysis of postoperative complications in the first 90 días after surgery. In the SBTKR group, 8 patients (6.5%) presented some thromboembolic complication during the postoperative period, while this event was observed only in 2 patients (1.5%) from the other group. Regardless of the age, BMI, or ASA of the patient (OR 4.5; 95% CI 0.91-22.5; p = 0.06). The analysis showed a statistically significant drop in postoperative hemoglobin, on average of 0.8 g/dl, in the SBTKR patient group compared to the UTKR group. (95% CI 0,44-1,13; p<0,001). A higher proportion of transfused patients was observed in the SBTKR group (40%). (OR=7,12; 95% CI 3,3 - 16; p<0,001).
We analyzed the cause of postoperative transfusion of the transfused patients taking into account two parameters: hemoglobin less than 8 g/dl and the clinical need of the patients (symptoms of hypotension, decay, difficulty to rehabilitate without pain, dyspnea). 59 patients were transfused (50 in the SBTKR group and 9 in the other group). Of these, 19 patients (32.2%) did not meet any transfusion criteria.

Conclusions

We consider the SBTKR a safe procedure, which does not increase postoperative complications compared to the UTKR. Although there is an increase in blood loss in the SBTKR, it does not generate clinical symptoms of relevance.