The impact of intravenous iron supplementation in elderly patients undergoing major surgery

Age and preoperative anaemia are risk factors for poor surgical outcome and blood transfusion. The aim of this study was to examine the effect of iron supplementation in iron-deficient (ID) elderly patients undergoing major surgery.

In this single-centre observational study, patients ≥ 65 years undergoing major surgery were screened for anaemia and ID. Patients were assigned to the following groups: A^- (no anaemia); A^-,ID⁺,T⁺ (no anaemia, iron-deficient, intravenous iron supplementation); A⁺ (anaemia); and A⁺,ID⁺,T⁺ (anaemia, iron-deficient, intravenous iron supplementation).

Of 4,381 patients screened at the anaemia walk-in clinic, 2,381 (54%) patients were ≥ 65 years old and 2,191 cases were included in analysis. The ID prevalence was 63% in patients with haemoglobin (Hb) < 8 g/dl, 47.2% in patients with Hb from 8.0 to 8.9 g/dl, and 44.3% in patients with Hb from 9 to 9.9 g/dl. In severely anaemic patients, an Hb increase of 0.6 (0.4; 1.2) and 1.2 (0.7; 1.6) g/dl was detected with iron supplementation 6-10 and > 10 days before surgery, respectively. Hb increased by 0 (-0.1; 0) g/dl with iron supplementation 1-5 days before surgery, 0.2 (-0.1; 0.5) g/dl with iron supplementation 6-10 days before surgery, and 0.2 (-0.2; 1.1) g/dl with supplementation > 10 days before surgery (p < 0.001 for 1-5 vs. 6-10 days). Overall, 58% of A⁺,ID⁺,T⁺ patients showed an Hb increase of > 0.5 g/dl. The number of transfused red blood cell units was significantly lower in patients supplemented with iron (0 (0; 3)) compared to non-treated anaemic patients (1 (0; 4)) (p = 0.03). Patients with iron supplementation > 6 days before surgery achieved mobility 2 days earlier than patients with iron supplementation < 6 days.

Intravenous iron supplementation increases Hb level and thereby reduces blood transfusion rate in elderly surgical patients with ID anaemia.