Mild anaemia indeed requires treatment

Prevention and management of acute reactions to intravenous iron in surgical patients

Absolute or functional iron deficiency is the most prevalent cause of anaemia in surgical patients, and its correction is a fundamental strategy within "Patient Blood Management" programmes. Offering perioperative oral iron for treating iron deficiency anaemia is still recommended, but intravenous iron has been demonstrated to be superior in most cases. However, the long-standing prejudice against intravenous iron administration, which is thought to induce anaphylaxis, hypotension and shock, still persists. With currently available intravenous iron formulations, minor infusion reactions are not common. These self-limited reactions are due to labile iron and not hypersensitivity. Aggressively treating infusion reactions with H₁-antihistamines or vasopressors should be avoided. Self-limited hypotension during intravenous iron infusion could be considered to be due to hypersensitivity or vascular reaction to labile iron. Acute hypersensitivity reactions to current intravenous iron formulation are believed to be caused by complement activation-related pseudo-allergy. However, though exceedingly rare (<1:250,000 administrations), they should not be ignored, and intravenous iron should be administered only at facilities where staff is trained to evaluate and manage these reactions. As preventive measures, prior to the infusion, staff should inform all patients about infusion reactions and identify those patients with increased risk of hypersensitivity or contraindications for intravenous iron. Infusion should be started at a low rate for a few minutes. In the event of a reaction, the very first intervention should be the immediate cessation of the infusion, followed by evaluation of severity and treatment. An algorithm to scale the intensity of treatment to the clinical picture and/or response to therapy is presented.

Effect of Pre-operative Anaemia on Post-operative Complications in Low-Resource Settings

BACKGROUND

In high-resource settings, even mild anaemia is associated with an increased risk of post-operative complications. Whether this is true in low-resource settings is unclear. We aimed to evaluate the effect of anaemia on surgical outcomes in the Republic of Congo and Madagascar.

METHOD

It is a retrospective chart review of 2064 non-pregnant patients undergoing elective surgery with Mercy Ships. Logistic regression was used to determine the association between pre-operative anaemia and pre-defined surgical complications, adjusted for age, gender, surgical specialty, and country.

RESULTS

The average age of patients was 27.2 years; 56.7% were male. Sixty-two percent of patients were not anaemic, and 22.7, 13.9 and 1.4% met sex-related criteria for mild, moderate and severe anaemia, respectively. In adjusted analyses, the severe anaemia group had an 8.58 [3.65, 19.49] higher odds of experiencing any surgical complication (p < 0.001) compared to non-anaemic patients. Analysis of each complication showed a 33.13 [9.57, 110.39] higher odds of unexpected ICU admission (p < 0.001); a 7.29 [1.98, 21.45] higher odds of surgical site infection (p < 0.001); and 7.48 [1.79, 25.78] higher odds of requiring hospital readmission (p < 0.001). Evaluating other anaemia categories, only those with moderate anaemia had a higher risk of requiring ICU admission (odds ratio 2.75 [1.00, 7.04], p = 0.04) compared to those without anaemia.

CONCLUSION

Our results indicate that in low-income settings, severe anaemia is associated with an increased risk of post-operative complications including unexpected ICU admission, surgical site infection and hospital readmission, whereas mild anaemia was not associated with increased post-operative complications.