The hidden blood loss in proximal femur fractures is sizeable and significant

Patients sustaining hip fractures experience blood loss as a direct result the fracture independent of surgery. The objective of this study was to quantify the expected non-surgical blood loss for proximal femur fractures using hemoglobin values.

A retrospective chart review of patients at a level 1 trauma center sustaining proximal femur fractures between October 2015 and January 2018 was performed. Patients were ≥30 years of age, had sustained intertrochanteric, subtrochanteric, or femoral neck fractures and had hemoglobin values documented at admission and after 12 h but before surgery. Patients with concomitant fractures, other hemorrhagic injuries, or blood transfusions before their second hemoglobin result were excluded. A multivariate linear regression model was constructed to evaluate the predictive ability of age, sex, BMI, number of comorbidities, fracture type, anticoagulation/antiplatelet therapy, admission hemoglobin, timing of surgical intervention and changes in electrolyte levels on subsequent hemoglobin values. Hemoglobin changes were compared between intertrochanteric, subtrochanteric, and femoral neck fractures and anticoagulant therapy types with Welch's tests.

119 patients were included. The mean age was 80.9 ± 10.81 years. Nearly 53% of subjects were using anticoagulation therapy. The mean drop in hemoglobin was 1.4 ± 1.03 g/dL. The multivariate linear regression model had statistically significant predictive ability (R = 0.91, p < 0.001). Independent predictors of hemoglobin decrease were number of comorbid conditions (p = 0.02), admission hemoglobin reading (p < 0.001), fracture type (p = 0.02), and time from admission to surgery (p = 0.03). Intertrochanteric fractures demonstrated the largest hemoglobin drops. Anticoagulation therapy had no effect on subsequent hemoglobin.

Proximal femur fractures cause a significant amount of blood loss prior to surgical intervention. Patients at particular risk include those with comorbidities, intertrochanteric fractures, low admission hemoglobin values, and increased time to surgery. The identification of demographic, fracture type, and treatment characteristics may help surgeons identify patients at the greatest risk for blood loss, and provide more effective perioperative care.