The objective of this study was to determine the clinical factors that are predictors for intraoperative transfusion in orthopaedic trauma patients. A retrospective chart review of patients admitted to a level I trauma center with isolated fractures was conducted. Variables such as gender, height, weight, body mass index, American Society of Anesthesiologists (ASA) classification, and medical comorbidities were assessed to determine likelihood of blood transfusion. A total of 1819 patients with isolated fractures were identified. ASA class was strongly associated with patients receiving intraoperative blood transfusion. For example, compared with patients with an ASA class I, patients with an ASA class IV were 14.71 times more likely to receive transfusion. Patients' ASA class is correlated with the need for intraoperative blood transfusion in patients undergoing orthopaedic surgery for isolated fractures. Institutional or departmental maximum surgical blood order schedule algorithms could use patients' preoperative ASA class to determine whether blood transfusion will be necessary during procedures.