Abstract P34: Variation in Transfusion Practice and Associated Postoperative Complications in Abdominally-Based Autologous Breast Reconstruction Surgery

Abstract

PURPOSE: Blood transfusion is the most frequently performed procedure in US hospitals. Despite its life-saving potential when clinically indicated, evidence shows that transfusion in some cases does not provide a significant clinical benefit to patients and thus does not justify its associated costs and risks. Increasing emphasis has been placed on reducing these potentially unnecessary transfusions, demonstrated by recently published guidelines from the American Association of Blood Banks (AABB) recommending restrictive hemoglobin thresholds for transfusion (≤7 g/dL). In plastic and reconstructive surgery, free flap procedures are associated with high utilization of blood transfusion, reported in the literature to be as high as 42%. The high volume of flap-based breast reconstructions makes this procedure an ideal target for quality improvement interventions related to blood transfusion practices. In this study, we assessed variation in transfusion practice and its associated clinical outcomes in a large cohort of breast reconstruction patients to identify potential targets for quality improvement. METHODS: After obtaining IRB approval, we extracted perioperative blood utilization data and hemoglobin transfusion triggers from two prospectively-collected anesthesia and blood management databases (Metavision and IMPACT Online) for all patients who underwent abdominally-based autologous breast reconstruction at the Johns Hopkins Hospital between 2009 and 2015. We defined hemoglobin transfusion triggers as the lowest measured hemoglobin level preceding a blood transfusion. We used ANOVA, Chi-squared, and linear regression to examine patient-level and surgeon-level variation in the use of overall blood transfusions, potentially unnecessary blood transfusions, and hemoglobin transfusion triggers. RESULTS: Of 653 patients, 65 (10%) received perioperative blood transfusions. Risk factors for increased blood utilization were higher ASA class (OR: 2.4; p=0.015) and younger age (OR: 1.2 for every 5-year decrease in age; p=0.008), with a trend for the presence of rheumatic comorbidities (OR: 3.7; p=0.098). Use of perioperative blood transfusions varied by surgeon (range: 5% to 24%; p=0.001), suggesting the presence of variation in transfusion practices. Mean hemoglobin trigger was 6.6 g/dL (±0.83 g/dL; range 3.4–8.2 g/dL). Hemoglobin triggers varied by surgeon (range: 6 g/dL to 7.5 g/dL; p<0.001) and patient age (p=0.031), with a trend for Charlson comorbidity index (p=0.093). Of the 65 patients that received blood transfusions, 16 patients (25%) had potentially unnecessary transfusions (hemoglobin triggers ≥7g/dL). Potentially unnecessary utilization of blood transfusion did not vary by surgeon (range: 1% to 4%; p=0.142), but was higher in TRAM flap reconstructions (OR: 9; p=0.001) and showed a trend for higher ASA class (OR: 3; p=0.076). Patients who received blood transfusions experienced worse clinical outcomes in terms of postoperative infections (p=0.006), Clostridium difficile infection (p=0.003), sepsis (p<0.001), and 30-day readmission (p<0.001). CONCLUSION: Use of perioperative blood transfusion varied among surgeons. However, there was no evidence for surgeon-level variation in potentially unnecessary perioperative transfusion. Transfusions were significantly associated with higher risk of perioperative infections and postoperative readmissions. These findings emphasize the importance of standardizing transfusion practices with the goal of minimizing unnecessary transfusions and their potential negative consequences.