Page 26 - ISAKOS 2018 Newsletter Volume 2

CURRENT CONCEPTS
Strategies to Minimize Blood Loss in TKR Surgery
TABLE I Summary of Strategies to Minimize Blood Loss in TKR Surgery
Introduction
Mihai Vioreanu, MD, FRCSI
Sports Surgery Clinic Dublin, IRELAND
and timely measurement • of Hgb
• Investigation of cause of low Hgb
• Administration of iron
supplements
• Cessation of
antiplatelet and anticoagulant medication
Despite significant advances in implant design and fixation leading to improved survival and function following total knee replacement (TKR), the blood loss associated with this procedure remains a concern. Estimates of blood loss following TKR surgery have ranged from 800 to 1,700 mL. Most of this blood loss is “hidden” and occurs during the immediate postoperative period as the majority of procedures are performed under tourniquet control.
The aims of minimizing blood loss in TKR surgery are to reduce or eliminate the need for postoperative blood transfusion while optimizing postoperative hemoglobin (Hgb) and maximizing oxygen-carrying capacity. Decreasing will enhance patient recovery and improve the final clinical outcome. The average Hgb loss associated with primary TKR surgery has been calculated to be 3.8 mg/dL. The blood- transfusion trigger should be individualized on the basis of the risks and benefits for each patient. Previous studies have demonstrated allogenic blood transfusion rates of as high as 39% in association with TKR surgery. Several studies have highlighted the disadvantages of allogenic blood transfusions, including an increased rate of medical postoperative complications, an increased duration of hospitalization stay, and increased mortality.
Blood-management strategies should be individualized on the basis of patient-specific risk factors, the anticipated difficulty of the procedure, the expected blood loss, and associated medical comorbidities. A multimodal, evidence-based strategy is needed to reduce transfusion rates, postoperative complications, readmission rates, the length of stay, and mortality. Such a multimodal strategy should incorporate preoperative, intraoperative, and postoperative protocols (Table I).
Preoperative Assessment and Optimization of Hgb Level
Several studies have demonstrated a relationship between the preoperative Hgb level and the need for blood transfusion after joint replacement surgery. The reported prevalence of anemia before arthroplasty surgery has ranged from 15% to 39%. Very few patients with a preoperative Hgb level of >15 g/dL require allogenic blood, whereas patients with a preoperative Hgb level of <11 g/dL have been reported to have a transfusion rate of 100%. Other factors that increase the risk for blood transfusion include increased weight (BMI >27 kg/cm2), an age of >75 years, male gender, and hypertension. In patients with multiple risk factors, optimizing the preoperative Hgb level is essential not only because doing so reduces the need for blood transfusion but also because it has a positive physiological impact on patient rehabilitation and functional recovery.
Ideally, all patients who are scheduled for elective TKR should undergo testing of the Hgb level within a timeframe that will allow for the treatment of a low Hgb level before surgery. At our institution, all patients are scheduled for an anesthetic consultation at least 4 weeks prior to the date of surgery. Any patient with anemia (Hgb <12 g/dL) is further investigated to determine the underlying cause and appropriate treatment. The most common reason for a low Hgb level in these patients is iron-deficiency anemia (low Hb and low ferritin). The options for optimizing the Hb level preoperatively include treatment with iron supplements and erythropoietin.
Iron supplements Can be administered orally or intravenously, but intravenous treatment appears to be more effective for raising Hb levels in a shorter period of time.
24 ISAKOS NEWSLETTER 2018: VOLUME II
Preoperative
• Assessment and optimization of Hgb level
• Routine
Intraoperative Postoperative
•
Efficient • surgical • technique and meticulous hemostasis
Use of
tranexamic • acid (TXA)
• Intravenous
• Topical
No drain use Use of tranexamic acid (TXA)
• Intravenous • Oral
Immobilization in flexion