Perioperative anemia - NYSORA | NYSORA

Perioperative anemia

Learning objectives

  • Optimize blood hemoglobin levels to avoid or minimize transfusion necessity during surgery


  • Anemia is a condition in which the number of red blood cells or the hemoglobin concentration within them is lower than normal
  • Hemoglobin is a protein in red blood cells (RBCs) and is responsible for transporting oxygen from the lungs to tissues and organs
  • Normal blood hemoglobin levels range from:
    • 13.8 – 17.2 g/dL in men
    • 12.1 – 15.1 g/dL in women 

Signs and symptoms

  • Fatigue
  • Shortness of breath
  • Paleness
  • Resting tachycardia

Note that these symptoms are unreliable as people with long-existing anemia might be asymptomatic

Causes and classification 

  • Anemia is classified depending on the size of the RBCs
Microcytic (MCV <80 fL)Normocytic Macrocytic MCV >100 fL
CausesIron deficiency
Anemia of inflammation
Sideroblastic anemia
Acute bleeding
Renal disease
Acute inflammation

Vitamin B12 deficiency
Folate deficiency
Myelodysplastic syndrome
Aplastic anemia
Liver and renal disease


Anemia, iron deficiency, erythropoietin (EPO), vitamin B12, folate, blood transfusion

Suggested reading

  • Hare GMT, Mazer CD. Anemia: Perioperative Risk and Treatment Opportunity. Anesthesiology. 2021;135(3):520-530.
  • Cascio MJ, DeLoughery TG. Anemia: Evaluation and Diagnostic Tests. Med Clin North Am. 2017;101(2):263-284.
  • Chernecky CC et al. Laboratory Tests and Diagnostic Procedures. 6th ed. Philadelphia, PA: Elsevier; 2013:621-623.

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