Preoperative anemia management with intravenous iron: a systematic review

Abstract

Background Iron deficiency anemia is a common condition in patients presenting for surgery, but despite its negative health impacts, the condition remains frequently unmanaged. Optimizing the patient's own red cell mass should be addressed in the preoperative period. Intravenous iron has been advocated as an effective treatment modality. Objectives The objective of this systematic review was to critically appraise and synthesize the best available evidence related to the effectiveness and economic aspects of intravenous iron administration on the correction of iron deficiency anemia in the preoperative period. Inclusion criteria Types of participants Adult patients 18 years of age and older receiving intravenous iron compared with those taking iron orally, and those who were not on iron or were transfused with red blood cells for the correction of anemia. Studies assessing the economic aspects of anemia management were also considered. Types of intervention(s)/phenomena of interest The quantitative component of the review considered studies that evaluated the management of anemia with iron infusions compared to oral iron treatment alone, oral iron in combination with erythropoietin, erythropoietin alone or hemoglobin correction with blood transfusion. The economic component of this review considered studies that evaluated the costs and benefits of iron infusions compared to oral iron treatment or hemoglobin correction with blood transfusion for the treatment of preoperative anemia. Types of studies The quantitative component of the review considered any experimental study design including randomized controlled trials (RCTs), non-RCTs and quasi-experimental studies for inclusion. The economic component of the review considered cost effectiveness, cost utility and cost benefit studies for inclusion. Types of outcomes The quantitative component of this review considered studies that reported on the impact of intravenous iron administration on: hemoglobin levels, red blood cell transfusion, length of stay in hospital, rate of readmission within 30 days of discharge, incidence of transfusion-related complications and changes in functional outcomes. The economic component of the review focused on cost benefits resulting from intravenous iron administration. Search strategy The search strategy aimed to find both published and unpublished studies. A three-step search strategy was utilized in this review. Studies published in English, German, Italian and Dutch from 2001 until December 2012 were considered for inclusion in this review. Methodological quality The studies were independently assessed by two reviewers using standardized critical appraisal instruments from the Joanna Briggs Institute. Data collection Quantitative data was extracted from papers included in the review using the standardized data extraction tool from the Joanna Briggs Institute, specifically the Meta Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI). Economic data was extracted from papers included in the review using the standardized data extraction tool from the Joanna Briggs Institute Analysis of Cost, Technology and Utilisation Assessment and Review Instrument (JBI-ACTUARI). Data synthesis This review set out to conduct both meta-analyses of the findings of effectiveness studies using JBI-MAStARI and pooling of economic findings using JBI-ACTUARI. Because of the number of studies found, this was not possible and the findings are therefore presented in tabular or narrative form. Results The quantitative component of the review identified two RCTs for inclusion with one of the trials favoring intravenous iron over oral iron for anemia correction. Only a subgroup could be included from the second trial and the results were inconclusive. Data was heterogeneous and did not allow a meta-analysis. The search for the economic component of the review revealed no examination of the cost effectiveness of preoperative correction of iron deficiency anemia with intravenous iron. Conclusions The review found insufficient data to make firm conclusions about the effectiveness of preoperative intravenous iron administration for the correction of anemia. Neither could we establish firm conclusions on the potential cost savings due to intravenous iron supplementation.