Post-Operative Hypertension after Total Knee Arthroplasty and the Effects on Transfusion Rates

Transfusions are a cause of significant patient morbidity as well as expense. Anesthesia literature has examined controlled intraoperative hypotension as a means for reducing blood loss and transfusions. Our hypothesis is that inversely increased blood pressure post-operatively would then lead to increased blood loss and transfusions. We examined 105 consecutive patients who underwent TKA. We found a significant odds ratio of 1.123 for pre-operative hematocrit. For post-operative blood pressure, we calculated an insignificant odds ratio of 1.007, proving no relationship between post-operative blood pressure and transfusions. This is the first study to examine increased post-operative blood pressure's contribution to transfusion rates. Although we confirmed that low pre-operative hematocrit contributes to increased transfusions, we did not find a relationship between post-operative blood pressure and transfusions.