Preoperative Anemia Treatment with Intravenous Iron Therapy in Patients Undergoing Abdominal Surgery: A Systematic Review

Abstract

Introduction Preoperative anemia is associated with increased morbidity, mortality, and healthcare costs. As a result of the increased incidence of chronic blood loss and iron deficiency anemia in abdominal surgery patients and its impact on patient outcomes, we systematically evaluated the quality of evidence for preoperative intravenous (IV) administration of iron to patients with anemia undergoing major abdominal surgery with the focus on clinical outcomes. Methods In this systematic review, PubMed, Cochrane, The Cumulative Index to Nursing and Allied Health Literature, Web Of Science, and Excerpta Medica Database databases were searched up to 2019 using specific keywords. Inclusion criteria were patients that were over 18 years of age, underwent abdominal surgery, and received an IV iron treatment in the preoperative setting. Results The nine studies included in the final systematic review do not provide consistent evidence of a reduced incidence of allogeneic blood transfusions with preoperative IV iron administration. However, IV iron administration did consistently cause a significant increase in hemoglobin levels relative to oral iron therapy or no iron. Conclusion Overall, these findings are consistent in that IV iron administration is highly effective at rapidly increasing hemoglobin levels in patients with iron deficiency anemia undergoing major abdominal surgery. Unfortunately, there is currently no evidence of reduced incidence of allogeneic blood transfusions or other enhanced outcomes. Supplementary Information The online version contains supplementary material available at 10.1007/s12325-021-01628-7.

Pre-operative iron increases haemoglobin concentration before abdominal surgery: a systematic review and meta-analysis of randomized controlled trials

“…However, no subgroup analysis was performed for patient who underwent abdominal surgery, and the effect on blood transfusion was not reported by another meta-analysis pooling only RCTs 22 . The population of patients undergoing abdominal surgery was specifically explored by a systematic review, which concluded that preoperative iron allowed increasing haemoglobin concentration, but did not allow decreasing the incidence of allogeneic blood transfusion 23 . The FAIRY trial also showed that haemoglobin concentration could also be increased by post-operative administration of iron in anaemic patients after gastrectomy 24 .…”

Causal associations between iron status and sepsis: a Mendelian randomisation analysis

“…Despite the lack of clear evidence of benefit in randomised trials, there is increasing use of intravenous iron both on and off label; often for symptoms attributed to iron deficiency. [2][3][4] Iron status is a complex trait, and no single biomarker reliably represents total body iron state.…”

“…Despite the lack of clear evidence of benefit in randomised trials, there is increasing use of intravenous and/or oral iron both on and off label; often for symptoms attributed to iron deficiency. [2][3][4] However, it is also clear that iron excess can be harmful, with people who are genetically predisposed to high iron (e.g. patients with mutations in HFE) developing a complex and broad range of syndromes, including an increased risk of infection.…”

Showing up for cardiac surgery with enough red blood cells

“…Prior evidence for the benefits of preoperative IV iron from meta-analyses and randomized trials has been mixed. IV iron has been shown to increase preoperative Hb in most patient populations, [3][4][5][6][7] and to decrease RBC transfusions in some series, [4][5][6][7] but not in others. 3,8 Furthermore, the magnitude of Hb increase with IV iron appears to be relatively small, in the range of 0.5 to 1.0 g/dl.…”

“…IV iron has been shown to increase preoperative Hb in most patient populations, [3][4][5][6][7] and to decrease RBC transfusions in some series, [4][5][6][7] but not in others. 3,8 Furthermore, the magnitude of Hb increase with IV iron appears to be relatively small, in the range of 0.5 to 1.0 g/dl. 6,7,9 In the recent PREVENTT Trial with 487 randomized patients, 9 a single high-dose of preoperative IV iron (ferric carboxymaltose, 1000 mg) was given in the treatment group, resulting in an Hb increase of about 0.5 g/dl, but no decrease in RBC transfusion requirement and no difference in discharge Hb, compared with placebo.…”