It isn’t only healthy subjects who can tolerate incredibly low hemoglobin levels. The FOCUS (Fluoxetine or Control Under Supervision) trial sought to determine whether a higher threshold for blood transfusion would improve recovery in patients who had undergone surgery for a hip fracture. Results showed that even among elderly patients with known coronary artery disease or multiple coronary risk factors, survival rates were higher postoperatively at 30 and 90 days among patients with a transfusion trigger of 8 g/dL compared to those with a higher transfusion trigger.

What Are the Indications for IV Iron?

Current knowledge suggests physicians shouldn’t be giving red cell transfusions to many patients who have severe anemia or blood loss. Nonetheless, these patients with severe anemia (Hb <9 g/dL) do require treatment for symptom management, and the fastest, most effective treatment is IV iron.

The concept of giving IV iron in a subset of ED patients with iron-deficiency anemia might seem foreign to most emergency physicians, but there are indications that should be considered when faced with a patient with iron-deficiency anemia or blood loss in the ED. They include:

• Severe iron-deficiency anemia (Hb <9 g/dL) especially if there is ongoing bleeding
• Rate of bleeding too brisk for oral iron
• Time-sensitive pressures (eg, an urgent surgical procedure; observational studies of the use of IV iron preoperatively for patients with anemia have shown a reduced rate of red cell transfusion being required)
• Severe anemia of chronic disease and evidence of iron deficiency (eg, ferritin <30 ug/L)
• Oral iron being poorly tolerated or the failure of an oral trial
• Poor oral absorption (due to conditions including gastric bypass, celiac disease, and gastritis)

Is IV Iron Safe?

The main contraindications to IV iron are active systemic infection (eg, suspected sepsis), as iron is a good microbial nutrient, and known allergic or hypotensive reactions in the past. Risks of administration include hypotension (1 to 2 percent) and serious allergic reactions including fatal anaphylaxis in fewer than one in 1 million. In patients with chronic kidney disease, IV iron may result in more infections and cardiovascular complications than oral iron. More common adverse reactions, which generally resolve spontaneously within 24 hours of administration of IV iron, include joint aches, muscle cramps, headache, chest discomfort, nausea, vomiting, and diarrhea.

How Do You Give IV Iron?

IV iron is given as iron sucrose (brand name Venofer) in an infusion of 300 mg in 250 mL of normal saline over two hours. After IV iron, and with ongoing oral supplementation, a patient’s hemoglobin will start to rise in three to seven days. You can expect a 0.1- to 0.2-point rise in the hemoglobin per day; after two to four weeks, the hemoglobin will have risen 2 to 3 g/dL. Ferrous sulfate (300 mg) contains 60 mg of elemental iron, and one tablet can be taken each night on an empty stomach at least two hours after meals with 500 mg of vitamin C to improve absorption. Patients should be counseled to avoid taking iron with calcium or magnesium supplements as they decrease iron absorption.

Resources from Emergency Medicine Cases Website

Podcast: Episode 65–IV Iron for Anemia in Emergency Medicine