Intravenous Iron Preparations for Patients Undergoing Elective Surgery: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines [Internet]

Excerpt

Preoperative anemia, which is often associated with iron deficiency, is a risk factor for poor outcome in patients undergoing surgery. According to the World Health Organization, anemia is defined as a circulating hemoglobin concentration of less than 130 g/L for men and less than 120 g/L for women. Iron deficiency is categorized as either absolute (iron deficiency anemia) or functional (anemia of inflammation, and also referred to as anemia of chronic disease). Several factors may contribute to iron deficiency anemia such as inadequate iron absorption, and bleeding due to an underlying disease condition. Iron is needed as a substrate for the bone marrow to produce erythrocytes. The prevalence of preoperative anemia varies between 5% and 76% depending on the age of the patient, the nature of the condition and the type of surgery planned; the prevalence being 26% for major orthopedic surgery, and 50% for cardiac surgery.

Treatment options for iron deficiency anemia include blood transfusion, oral iron, and intravenous iron. Traditionally, the focus was on the use of blood transfusion to manage anemia in the preoperative phase. However, blood transfusion is associated with risks such as infection, transfusion reaction, postoperative complications, and extended hospital stay.,, Furthermore, blood transfusion may have substantial cost implications. Oral iron is inexpensive and easy to administer but is associated with gastrointestinal side effects such as abdominal pain, diarrhea, constipation and dyspepsia which negatively impact compliance. Iron dextran formulations were developed both for intramuscular and intravenous administration, however due to the associated adverse effects, they were phased out. Since then, various formulations of intravenous iron (such as iron sucrose, ferric gluconate, ferrumoxytol, ferric carboxymaltose, iron isomaltiside) have been developed. These newer formulations have shown promise in treating anemia in a number of disease conditions (such as inflammatory bowel disease, chronic heart failure and chronic kidney disease. There is some suggestion that intravenous iron may be a useful treatment option for iron deficient anemia in patients undergoing surgery.

The purpose of this report is to review the clinical effectiveness and cost-effectiveness of intravenous iron preparations administered preoperatively, for iron deficient adult patients undergoing elective surgery. Additionally, this report aims to review the evidence-based guidelines regarding the use of intravenous iron preparations administered preoperatively, for iron deficient adult patients undergoing elective surgery (i.e., any surgery scheduled in advance of the operation).

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