Identifying missed opportunities for the preoperative management of anemia in oncologic liver surgery

Abstract

Background: Patient blood management (PBM) is a multidisciplinary approach to minimizing unnecessary blood product exposure. In liver surgery, preoperative anemia is associated with a three-fold increase in blood transfusion risk, and blood transfusions are independently associated with increased morbidity and mortality. Identifying anemia at a sufficient time prior to surgery is therefore imperative for treatment to be applied. Barriers to effective PBM include lack of perioperative bloodwork and limited time to initiate management between consultation and surgery. This study aims to determine the feasibility and barriers of adequate PBM for those undergoing liver resection for oncologic indications. Methods: Patients who underwent liver resection at one tertiary center were examined retrospectively (January 2010-May 2017). Eligible patients had at least one clinic visit prior to surgery. Patients with non-oncologic indications for liver resection were excluded. Demographic variables collected include age, gender, indication for surgery, and existing comorbidities. Outcomes of interest included time from consent to surgery, anemia prior to consent and surgery dates, rate of adequate bloodwork collected prior to surgery (CBC, Ferritin, and Vitamin B12), rate of iron/B12 therapies initiated prior surgery, and rate of transfusion. Anemia was defined as hemoglobin below 120 g/L for women and 130 g/L for men according to the World Health Organization definition. Results: A total of 371 patients underwent liver resection for oncologic indications during the study period. The median age was 64 years and 58% were male. The most common indication was colorectal liver metastases (62%). Preoperative chemotherapy was administered in 62% of patients. The median time between consent and surgery was 24 days and 79% of patients had at least a 2-week wait interval prior to surgery. A total of 257 patients completed bloodwork within 3 months before consent, of which 41% were anemic. Among those, 12% had microcytic anemia (MCV < 80 fL), 11% had ferritin levels reported, and 2% had B12 levels reported. After consent, a total of 315 patients (85%) completed bloodwork, of which 31% were anemic. Among those, 12% had microcytic anemia, 1% had preoperative ferritin levels reported, and none had B12 levels reported. Of those with preoperative anemia, 14% received iron therapy before surgery, of which 6% received intravenous iron infusion and 12% received vitamin B12. In total, 25.3% of all patients received postoperative blood transfusions, and 46% of patients with anemia received blood transfusions. Conclusion: Almost one third of patients had anemia prior to oncologic liver surgery, which resulted in a very high risk of transfusion. While almost all patients underwent bloodwork prior to surgery, it was inadequate for most of those with anemia. Most anemic patients had sufficient time between consent and surgery, and could thus have been considered for intravenous iron therapy as part of a PBM program.