What is the proper procedure for obtaining informed consent from a patient for an iron infusion?

How to Consent a Patient for Iron Infusion

Inform the patient that iron infusion is a safe and effective treatment for iron deficiency, with serious allergic reactions being exceedingly rare (less than 1 in 200,000 to 250,000 administrations), but that they will be monitored closely during and after the infusion in a facility equipped to manage any reactions. 1, 2, 3

Timing and Setting of Consent

• Provide information about the iron infusion as early as possible, ideally at pre-assessment or time of booking, using written materials the patient can review at home 1
• Allow sufficient time for the patient to ask questions and come to a considered decision—immediately before the procedure is not acceptable for providing new information 1
• Ensure the discussion occurs with adequate time for the patient to understand the broad nature of the procedure before finally consenting 1
• If the patient does not speak English, use a professional interpreter—never rely on family members or friends to translate, as this ensures accuracy and reduces coercive influence 1

Essential Information to Discuss

Benefits of Iron Infusion

• Primary benefit: Rapid correction of iron deficiency anemia to improve quality of life, energy levels, and hemoglobin 2
• Modern formulations allow total dose infusion in 15-60 minutes, avoiding multiple clinic visits 2
• Superior efficacy compared to oral iron, especially when oral iron has failed, is not tolerated, or in the presence of inflammation 2, 4

Risks and Side Effects to Explain

Common/Minor reactions (not life-threatening):

• Headache, flushing, muscle aches, joint pain, or flu-like symptoms that can be managed with NSAIDs 5
• Nausea or mild discomfort during infusion 1
• Temporary skin discoloration at the infusion site if extravasation occurs 2

Rare but serious reactions:

• Anaphylaxis occurs in less than 1 in 200,000 administrations but requires immediate treatment 1, 2
• Complement activation-related pseudo-allergy (CARPA/Fishbane reaction) causing symptoms like shortness of breath, chest tightness, or blood pressure changes—this is physiologically different from true allergy and is managed differently 1, 6
• Respiratory symptoms including transient cough, shortness of breath, or rarely bronchospasm 6

Delayed effects:

• Low phosphate levels (hypophosphatemia) may occur, particularly with repeat infusions, requiring monitoring in some patients 1, 2

Contraindications and Risk Factors

Absolute contraindications:

• Known hypersensitivity to the specific iron formulation 2
• Active infection (iron should not be given until infection is treated) 2
• Pregnancy before 13 weeks gestation 1

Higher risk patients requiring extra caution:

• History of severe asthma or eczema 6
• Mastocytosis 6
• Multiple drug allergies 2, 7
• Prior reaction to IV iron 6, 7

Monitoring and Safety Measures

• The infusion will be administered in a facility with resuscitation equipment and staff trained to manage reactions 2, 3
• The infusion will start at a slow rate for the first few minutes, with close observation during the first 10 minutes 1, 3
• Vital signs will be monitored during the infusion 3
• The patient must remain for observation for at least 30 minutes after completion and until clinically stable 2
• Blood tests will be repeated 8-10 weeks after infusion to assess response 2

What the Patient Should Report

• During infusion: Any symptoms including itching, rash, chest tightness, difficulty breathing, dizziness, or feeling unwell 2
• After discharge: Persistent headache, muscle/joint pain, fever, or any concerning symptoms 5
• Delayed symptoms: Unusual fatigue, bone pain, or muscle weakness (possible signs of low phosphate) 2

Documentation Requirements

• Document the discussion clearly in the patient's notes or on the anaesthetic/procedure record, including the patient's questions and your responses 1
• Record specific risks discussed, alternatives offered, and the patient's understanding 1
• If the patient has qualified consent (e.g., religious objections to certain treatments), document this specifically with the patient's reasons and your explanation of consequences 1
• Many facilities require a formal consent form to be completed and signed for IV iron as it is a therapeutic intervention 1

Special Considerations

For patients refusing certain aspects of care:

• Respect qualified consent (e.g., Jehovah's Witnesses may accept iron infusion but refuse blood transfusion) 1
• Document the precise nature of any restrictions and ensure the patient understands the implications 1

For patients with limited capacity:

• Ensure the patient has sufficient mental capacity to understand the information provided 1
• If capacity is questionable, involve senior colleagues early and consider whether the patient can retain and weigh the information to make a decision 1

Written information:

• Provide evidence-based leaflets or online resources in the patient's language 1
• Ensure Braille or large-print versions are available for visually impaired patients 1

Common Pitfalls to Avoid

• Do not administer iron infusions in facilities without resuscitation capabilities or trained staff 2
• Do not provide consent information for the first time immediately before the procedure 1
• Do not use family members as interpreters for non-English speaking patients 1
• Do not withhold information about risks simply because it might make the patient anxious—this is only acceptable if disclosure would pose a serious threat to the patient's health 1
• Do not measure iron studies too early after infusion; wait the full 8-10 weeks for accurate assessment 2