Abstract
Perioperative blood conservation remains an important topic today in order to reduce complications, improve function, and facilitate recovery after a total knee replacement (TKR). Studies have shown that the degree of postoperative anemia is related to an increase in complications. A greater blood loss and need for transfusion is associated with a higher risk of infection, a slower recovery process, increased morbidity to patients, as well as an increased cost to the health care system.
Typical blood loss estimates range from 800cc to over 1700cc, when accounting not only for intraoperative but postoperative blood loss. Several strategies have been developed to help mitigate the risk of perioperative blood loss and need for subsequent transfusion.
Firstly, preoperative measures such as vitamin and mineral supplementation can ensure the starting hemoglobin and red cell count are maximised. Additionally, erythropoietin can be helpful in refractory cases of preoperative anemia. Preoperative autologous blood donation was used extensively in the past, but has fallen out of favor due to its inefficiency and cost.
Intraoperatively, measures such as the use of a tourniquet, meticulous technique, and expeditious surgery can help reduce blood loss. The most effective method, however, has been the use of tranexamic acid (TXA). TXA, an antifibrinolytic compound, has been extremely effective at reducing perioperative blood loss without increasing the risk of thromboembolic events. TXA can be used topically or intravenously. Other methods that can reduce intraoperative blood loss include the use of fibrin sealants, applied to the soft tissues and bony surfaces around the knee.
Postoperatively, the avoidance of wound drains is associated with a higher blood count and reduced transfusion risk. Alternatively, drainage reinfusion systems can be used to raise the postoperative blood count, particularly in cases of bilateral TKR.
