Patients who are about to undergo orthopaedic surgery should be screened for anaemia, say Adelaide researchers who found anaemia was common in this group of patients.

In the study Head of Clinical Haematology at the Royal Adelaide Hospital Professor Bik To and colleagues screened almost 700 patients scheduled for joint surgery between 2010 and 2013.

They found that 17% (n=120) were anaemic, and around half of these patients had iron deficiency anaemia.

Interestingly, serum ferritin < 30ug/L alone did not identify iron deficiency in 80% of patients with iron deficiency, the study authors noted.

“This [finding] compels one to reconsider the reliability of serum ferritin of 100 ug/L as a cut-off for possible iron deficiency,” they said.

“It is possible that the serum ferritin became elevated as an acute phase reactant in this patient group with advanced degenerative joint disorder and other many comorbilities,” they suggested.

Treatment was effective in improving the pre-operative haemoglobin and reducing perioperative transfusion rates, the researchers found.

However the general unavailability of erythropoietin limited effective intervention in the non-iron deficient anaemic patients.

It was important to screen, and where possible, correct the preoperative haemoglobin, the researchers advised.

“The number of transfusion events for elective orthopaedic surgery is directly related to the preoperative haemoglobin, that is, the lower the haemoglobin, the more likely the patient would need transfusion and the more units of blood are transfused,” they wrote in their paper published in the Internal Medicine Journal.

“It is important that sufficient time be given preoperatively for assessment of patients who are anaemic, preferably with a period of 4-6 weeks preoperatively to allow for appropriate diagnosis and treatment,” they added.