Liberal and Restrictive Blood Transfusion Strategies in Orthopedic Surgery: Risk Factors for Surgical Site Infection

Abstract

Background: The identification of risk factors for infections in surgical patients with lower-limb fractures and blood transfusions has increased in recent years. Surgical site infections (SSIs) increase hospitalization, care costs, and patient suffering. Correction surgery for lower-limb fractures and blood transfusion is quite common between surgical procedures. The aim of this study was to describe the relationship between blood transfusion and SSI in patients undergoing orthopedic surgery on lower limbs. Methods: We conducted a prospective cohort study to identify risk factors for SSI in blood transfused patients undergoing fracture repair in lower-limb surgeries between February 2017 and May 2019 in 2 reference tertiary-care hospitals in Belo Horizonte, a city of 3 million people in Brazil. Data regarding patient characteristics, surgical procedures, blood transfusions, and surgical infections were collected. Patient characterization was performed by calculating the absolute and relative frequencies of categorical variables and calculating mean, median, minimum, maximum, standard deviation, and coefficient of variation for quantitative variables. The incidence of surgical site infection, the risk of postoperative hospital death, and the total length of hospital stay were calculated by point estimates and 95% confidence intervals identified by statistical tests of bilateral hypotheses, considering the level of significance of 5%. A multivariate analysis (logistic regression) was performed to identify SSI risk factors. Results: Patients who had an indication for blood transfusion (n = 38) but who did not receive blood (n = 4) had significantly lower hemoglobin, comparing discharge with admission, than the group who received blood. Intraoperative transfusion was a risk factor for SSI (OR, 4.7) (Fig. 1). Among the 205 patients with no indication for transfusion, 98 received blood even without the indication: there was no difference in hemoglobin outcome when discharge and admission were compared, and the 98 patients were exposed to unnecessary risk. Regarding restrictive versus liberal transfusion strategies, there were differences in the variables, age (P = .000), duration of surgery (P = .003), number of comorbidities (P = .000), body mass index (BMI) (P = .027), previous hemoglobin (P = .000), and high hemoglobin (P = .000), considering the transfusion practice employed (Fig. 2). Conclusions: The indications for and definition of protocols and careful evaluation of blood transfusion are critical to avoid infectious complications in orthopedic patients with lower-limb fractures.Funding: NoneDisclosures: None