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Updates on Perioperative Blood Management

Anemia is an independent risk factor associated with significant morbidity and mortality. As such, managing and treating a patient’s anemia is critical to reducing the associated risks of bleeding and transfusions.1 Patient blood management is a multidisciplinary approach to managing anemia and is based on three pillars: the detection and treatment of preoperative anemia, reducing intraoperative blood loss, and optimizing a patient’s physiological tolerance toward anemia.1,2

Blood management starts preoperatively to identify risk factors and treat preoperative anemia. Reviewing medical records and interviewing the patient before surgery can identify risk factors for transfusion and the need for adjuvant therapy. Preoperative labs should be ordered to diagnose preexisting anemia so that it can be treated early. The American Society of Anesthesiologists (ASA) recommends iron supplementation for patients with iron deficiency anemia and suggests erythropoietin in select populations.3 The preoperative appointment should also be used to educate patients of the potential risk associated with transfusions, instruct when to discontinue anticoagulants and antiplatelets, and discuss the option for autologous blood transfusion if needed.

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The second pillar focuses on reducing the risk of intraoperative bleeding. For surgeons, this means using laparoscopic or minimally invasive surgeries when possible. For anesthesiologists, this means creating an appropriate anesthetic plan with specific pharmacologic interventions. For example, utilizing neuraxial techniques compared to general anesthesia has been shown to decrease blood loss likely due to the to lower blood pressures associated with a sympathetic blockade.4 As for pharmacologic interventions, prophylactic antifibrinolytics (e.g., tranexamic acid) can reduce bleeding and decrease the risk of transfusions.3 Other strategies that help optimize hemostasis are maintaining normothermia and preventing acidosis or hypocalcemia.1

The third objective of patient blood management involves optimizing a patient’s physiology to tolerate anemia better. This means ensuring adequate oxygenation, transportation, and utilization. For example, sepsis or pain can increase the metabolic demand for oxygen. As such treating infections and ensuring adequate analgesia can help decrease metabolic oxygen consumption.1 Additionally, ensuring proper ventilation, oxygenation, and organ perfusion intraoperatively all help optimize tolerance for anemia.

However, if a patient does require a transfusion, utilizing a restrictive approach is has been shown to be safe with improved outcomes compared to a liberal strategy.5,6 The National Institute for Health and Care Excellence (NICE) recommends a hemoglobin concentration of 7 g/dl as a threshold to transfuse for those without major hemorrhage or acute coronary syndrome (ACS). For those with ACS, this threshold is increased to 8 g/dl.6 ASA recommends a wider range of 6 to 10 g/dl but to consider other factors such as rate and magnitude of bleeding, volume status, signs of organ ischemia, and cardiopulmonary reserve.3 Overall, the decision of when to transfuse is based on clinical judgment and should take into account more than lab values. It is important that physicians stay current on the practice of blood management to help reduce transfusion overuse while improving patient outcomes.

References:

  1. Desai N, Schofield N, Richards T. Perioperative patient blood management to improve outcomes. Anesth  Analg. 2018;127(5):1211-1220.
  2. Muñoz M, Gómez-Ramírez S, Kozek-Langeneker S. Pre-operative haematological assessment in patients scheduled for major surgery. Anaesthesia. 2016;71 Suppl 1:19-28.
  3. Practice Guidelines for Perioperative Blood Management, an Updated Report by the American Society of Anesthesiologists Task Force on Perioperative Blood Management*. Anesthes. 2015;122(2):241-275.
  4. Richman JM, Rowlingson AJ, Maine DN, Courpas GE, Weller JF, Wu CL. Does Neuraxial Anesthesia Reduce Intraoperative Blood Loss? A Meta-Analysis. J Clin Anesth. 2006;18(6):427-435.
  5. Gupta PB, DeMario VM, Amin RM, et al. Patient Blood Management Program Improves Blood Use and Clinical Outcomes in Orthopedic Surgery. Anesthesiology. 2018;129(6):1082-1091.
  6. Padhi S, Kemmis-Betty S, Rajesh S, Hill J, Murphy MF. Blood Transfusion: Summary of NICE guidance. BMJ. 2015;351:h5832.
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