The Effect of Body Mass Index on Posttraumatic Transfusion after Pelvic Trauma

Abstract

The impact of body mass index (BMI) on posttraumatic blood transfusion after pelvic trauma is not well known. We conducted a retrospective review of trauma registry data over a 5-year period. Patients were stratified by BMI as normal: less than 25 kg/m2, overweight: 25 to 29.9 kg/m2, obese: 30 to 39.9 kg/m2, and morbidly obese: 40 kg/m2 or greater. Fractures were identified as “likely to receive transfusion” based on literature. Multivariable logistic regression modeling evaluated the relationship between BMI and initial posttraumatic transfusion. A second regression model was created to test the effect of BMI after adjusting for fractures “less likely to receive transfusion.” Sixty-six of 244 patients (27.3%) received transfusion (mean: 1.1 ± 2.3 units). Morbid obesity was associated with transfusion (less than 55.6 vs 24.8%; P < 0.05) and units of total blood transfused (2.2 ± 2.9 vs 1.0 ± 2.2 mL; P < 0.05). The average age of patients who received a blood transfusion was significantly older compared with patients who did not receive a transfusion (45.4 ± 18.8 vs 36.1 ± 16.1 years; P < 0.05). After adjusting for potential confounders, morbid obesity was a significant risk factor for transfusion (odds ratio [OR], 4.1; 95% confidence interval [CI], 1.4 to 12.0). Adjusting by age and fracture patterns “less likely to receive transfusion,” morbid obesity remained a risk factor for transfusion (OR, 4.5; 95% CI, 1.5 to 12.9). Morbid obesity represented a significant risk factor for posttraumatic transfusion in isolated pelvic trauma, even for fracture patterns “less likely to receive transfusion.”

Preoperative Blood Loss of Isolated Acetabular Fractures

“…Richards et al 17 evaluated the effect of BMI on transfusion rates in isolated pelvic trauma, and they found that morbid obesity with BMI greater than 40 kg/m 2 is a significant risk factor for posttraumatic transfusions in isolated pelvic trauma. Although our study population had a wide range of BMI, the mean BMI of those transfused preoperatively (28.64 kg/m 2 ) and those without (29.52 kg/m 2 ) was not significantly different.…”

Is Obesity Associated With an Increased Risk of Complications After Surgical Management of Acetabulum and Pelvis Fractures? A Systematic Review

“…Several studies have evaluated the role of BMI on complication rates after acetabulum/pelvis trauma with the inclusion of patients treated both with and without surgery. 27 - 29 Although these more inclusive studies are valuable, they may have included injuries that did not meet surgical indications, patients too sick to have surgery, or had other important confounding issues. This constraint is also a limitation of database studies, which is why we chose to exclude them from this analysis despite the advantages of their large size.…”