From the Guidelines
Patients with iron deficiency anemia should receive intravenous iron supplementation preoperatively to minimize perioperative risks and improve outcomes. This approach is supported by the most recent and highest quality study, which showed that preoperative intravenous iron supplementation decreased blood transfusion by 16% and was not associated with increased incidence of any adverse effects 1. The 2022 guidelines for perioperative care in elective abdominal and pelvic surgery also recommend investigating and correcting anemia preoperatively, with intravenous iron being a preferred option for patients with iron deficiency anemia 1.
Preoperative Optimization
Preoperative optimization is essential for patients with iron deficiency anemia.
- Intravenous iron supplementation, such as iron sucrose 200mg or ferric carboxymaltose 1000mg, is recommended for moderate to severe deficiency, ideally 2-4 weeks before surgery to allow for erythropoiesis.
- Oral iron supplements, such as ferrous sulfate 325mg daily, may be sufficient for mild cases with adequate time before surgery. The recent PREVENTT trial showed that the use of intravenous iron in patients with all types of anemia before major open elective abdominal surgery increased hemoglobin concentrations before surgery but did not reduce the frequency of blood transfusion, mortality, in hospital complications, length of stay or quality of life relative to a placebo 1. However, there was a reduced risk of readmission to hospital for complications in those patients who received intravenous iron.
Intraoperative Management
During anesthesia, it is crucial to maintain hemodynamic stability by:
- Avoiding excessive blood loss
- Using blood-conserving techniques
- Considering cell salvage for major procedures
- Employing multimodal analgesia to reduce opioid requirements
- Maintaining normothermia and ensuring adequate oxygenation with higher FiO2 (0.4-0.6) as needed
Postoperative Care
Postoperatively, it is essential to:
- Continue iron supplementation
- Monitor for signs of cardiac decompensation, especially in patients with comorbidities The rationale for these approaches stems from iron deficiency's impact on oxygen-carrying capacity, which can lead to tissue hypoxia, reduced exercise tolerance, and impaired wound healing 1. Iron deficiency also affects mitochondrial function and can cause restless leg syndrome, which may complicate postoperative recovery. Early identification and correction of iron deficiency helps optimize surgical outcomes by improving oxygen delivery and reducing transfusion requirements.
From the Research
Anaesthesia for Patients with Iron Deficiency
- Iron deficiency is a common condition that can affect patients undergoing surgery, and it is essential to manage it properly to reduce the risk of complications 2, 3.
- Preoperative iron supplementation can help improve hemoglobin levels and reduce the need for blood transfusions during surgery 2, 4.
- Intravenous iron supplementation is effective in improving hemoglobin levels and reducing the need for blood transfusions, especially when administered more than 7 days before surgery 2, 3.
- The use of erythropoiesis-stimulating agents (ESAs) in combination with iron supplementation may also be effective in reducing the need for blood transfusions 4.
- High-dose intravenous iron therapy can be effective and safe in treating severe iron deficiency anemia, and it may be considered as a first-line therapy in outpatients with this condition 5, 6.
Management of Iron Deficiency Anemia
- Preoperative anemia affects 30-40% of patients undergoing major surgery and is an independent risk factor for perioperative blood transfusion, morbidity, and mortality 3.
- Absolute or functional iron deficiency is the leading cause of preoperative anemia, and it should be detected and corrected prior to major surgical procedures 3.
- Postoperative anemia is even more common (up to 80-90%) due to surgery-associated blood loss, inflammation-induced blunted erythropoiesis, and/or preexisting anemia 3.
- Intravenous iron should preferentially be used in cases of moderate-to-severe iron deficiency anemia, concomitant use of ESAs, short time to surgery or nonelective procedures, and for postoperative anemia management 3.
Effectiveness of Iron Supplementation
- Iron supplementation with or without ESAs can reduce the number of patients and units transfused, although the certainty of evidence varies depending on the specific intervention and outcome 4.
- High-dose intravenous iron therapy can increase hemoglobin levels and reduce the need for blood transfusions, although the optimal dosing regimen is not well established 5, 6.
- The use of ferric carboxymaltose, a high-dose intravenous iron formulation, has been shown to be effective and safe in treating severe iron deficiency anemia 6.