Retrospective Evaluation of Pharmacist Assisted Total-Dose Iron Sucrose Protocol in Patients with Iron Deficiency Anemia

Introduction

Iron deficiency anemia (IDA) is the leading cause of anemia in the United States. Although oral iron formulations can correct IDA, they are generally poorly tolerated due to gastrointestinal side effects and may require long term use to maintain normal hemoglobin. Intravenous iron is an alternative to oral iron especially in adults who cannot tolerate or absorb oral iron. Intravenous iron preparations avoid problems of malabsorption and can quickly correct IDA but little data exists on the safety or efficacy in patients without chronic kidney disease (CKD) with or without dialysis, heart failure, uterine bleeding, and inflammatory bowel disease. Long term safety of IV therapy is not well established. At a tertiary midwestern medical center between 2008-2018, a dosing protocol was implemented with staff pharmacists aiding physicians in identifying candidates for total dose infusions (TDI) and calculating iron deficits for patients with IDA. We sought to define the safety and efficacy of IV iron in adult ≥ 18 years old with IDA.

Methods

We conducted a retrospective chart review of patients at a tertiary midwestern medical center from 8/1/14 to 8/1/17. Inclusion criteria includes adult patients ≥ 18 years old who were seen in either the inpatient or outpatient setting who received iron sucrose in doses ≥ 300mg. We excluded patients who were receiving the drug for anemia associated with chronic kidney disease or receiving renal replacement therapy. Data was collected and secured using a standardized data extraction sheet administered via online survey. We extracted demographic information, amount of iron sucrose given, and laboratory values such as discharge hemoglobin, serum iron studies, and liver function tests (prior to and after administration). We assessed physician and nurses' notes from the electronic medical record for the development of adverse effects due to TDI. In patients with a 14 to 28 day follow-up labs in our health-system, we assessed hemoglobin and liver function tests. We compared pre-TDI hemoglobin to follow-up hemoglobin in matched patients using the paired student t -test.

Results

A total of 238 patients received iron sucrose TDI for IDA during the study period. 193 patients (81%) were female, and the mean age in our cohort was 60.6 years. Mean weight of our patients was 80.92 Kg. Mean Pre-TDI hemoglobin was 8.76 g/dL. Out of the 238 patients, initial iron studies were completed on 201 patients (88%) with a mean ferritin of 80 ng/mL (range 1.0-607.0 ng/mL) and iron saturation 6.8% (range 1.0-25.0%), respectively. The mean dose of iron sucrose in the total cohort was 680 mg (range 300-2500 mg). Adverse effects attributable to iron sucrose were reported in 15 patients with nausea being the most common effect (7/238, 2.9%). No anaphylaxis episodes were reported unlike prior formulations. Eighty-one patients had accessible labs available between 14 to 28 days. When matching the patients' preadmission and postadmission records, a hemoglobin increase of 2.1 g/L was found (p < 0.001). No increase in liver function tests were found in any patient

Conclusions

A pharmacist assisted iron sucrose TDI protocol for patients with IDA successfully increased serum hemoglobin and was well tolerated with nausea being the most common side effect. Unlike, prior formulations where anaphylaxis was the most common side effect this was never reported in our patient population, which further proves that newer formulations of IV Venofer have fewer side effects. Pharmacy assisted protocols will increase the number of patients who are identified as candidates and correctly treated for iron deficit with intravenous iron therapy.