Iron Deficiency Anaemia
Iron deficiency anaemia is a frequent problem in primary care. While it is often present in hospitalised patients, it is generally not the primary reason for admission and may go unnoticed.
Iron deficiency anaemia may indicate a serious underlying condition such as malignancy so determination of the underlying cause is important.
The cause of anaemia is often not considered and may lead to a reflex decision to transfuse without considering whether there is a reversible cause such as iron or vitamin deficiency.
Oral Iron
Oral iron generally is first line therapy in the non-dialysis/chronic kidney disease setting. Intravenous iron is used in selected cases in consultation with a specialist.
Adequate doses of oral iron can raise the haemoglobin level by around 10g/L per week in adult patients (equivalent to a unit of red cells) in the setting of iron deficiency anaemia.
In patients with iron deficiency and significant anaemia who need transfusion (for example if decompensated or acutely bleeding), iron stores still need to be replaced.
Many iron tablets contain only small amounts of elemental iron (as low as 5mg) so it is essential to ensure that a preparation with an adequate of dose of elemental iron is prescribed to treat iron deficiency anaemia (to deliver around 100-200mg of elemental iron per day in adults).
Even when patients are prescribed a particular iron tablet by their doctor, they may start taking an alternative iron tablet from the pharmacy or supermarket which has too little iron to be effective in the setting of anaemia. Often these tablets are recommended or advertised as having no side effects (which is because they have so little iron in them).
BloodSafe has developed a patient information sheet about iron tablets and a laminated chart for doctors illustrating the iron tablets that have sufficient iron to deliver a therapeutic dose to treat anaemia.
Intravenous Iron
Transfusions are sometimes prescribed because of a lack of familiarity with intravenous iron preparations and how to use them as well as the mistaken belief that the risks are greater than with blood transfusion.
The main serious risk of IV iron is severe allergy/anaphylaxis but this risk is less than the serious risks of a blood transfusion.
A 2004 BloodSafe audit of patients undergoing elective joint replacement surgery found that 18% were anaemic prior to surgery. Some of these patients may have had iron deficiency and treatment in advance of surgery could have reduced the need for transfusion.
A 2006 audit of 221 transfusion episodes across six public hospitals found that in 25% the patients had either confirmed or suspected iron deficiency anaemia (based on iron studies and/or full blood count). Improving anaemia management goes hand in hand with improving transfusion practice and increasingly the activities of BloodSafe are focused around a comprehensive and individualised approach to blood management.
The cost of blood and blood products is largely hidden but consumes more than $600 million every year in Australia. This does not include the cost of the transfusion process or complications.
We also have an ethical responsibility to blood donors to ensure the best use of their precious gifts and this necessarily means ensuring that the guidelines, tools and iron preparations required for best practice are available.
It is likely to that such strategies will also contribute to management of the burden of anaemia which will increase with our ageing population.