Objective: Evaluating blood losses in total knee arthroplasty (TKA), comparing data from a group in which tourniquet was opened before surgical closure to another group where the tourniquet was opened after closing.

 

Methods: We have collected data from 96 patients who underwent TKA in Centro Hospitalar de São João (Oporto - Portugal) between January 2015 and February 2016. Patients were divided into two groups according to the time of tourniquet opening during surgery: Group 1 included patients whose tourniquet was opened after surgical closure and Group 2 included patients whose tourniquet was opened before surgical closure. Values like pre and post operative hemoglobin, total volume drained and estimated blood loss (calculated by Gross method) were compared between the two groups.

 

Results: 18 men and 78 women were included in the study. The decrease of hemoglobin was, on average, 3.1 in Group 1 and 2.8 in Group 2 (p=0.260). The estimated blood loss was 1092 ml in Group 1 and 1029 ml in Group 2 (p=0.492). The transfusion rate was similar in both groups (Group 1 3.7% vs. 2.4% in Group 2, p=0.999).

 

Conclusions: No significant differences between the two groups were found that allow us to say that tourniquet opening prior to surgical closure decreases the blood losses in the TKA.

 

Key words: Total Knee Arthroplasty, Blood loss, Tourniquet.