Performance of Multiple Massive Transfusion Definitions in Trauma Patients

Introduction: Massive transfusion (MT) is defined as the administration of ≥ 10 U of packed red blood cells (PRBCs) in 24 hours. Alternative definitions have been proposed which have not been compared regarding mortality or multiorgan failure (MOF). The objective is to compare the discriminative ability of proposed definitions of MT concerning mortality and MOF. Materials and methods: Patients with trauma team activation in a level I trauma hospital of Cali, Colombia, between 2015 and 2017 were included. Demographics and trauma characteristics were evaluated. The following MT definitions were measured: ≥ 50 U of total blood products in 24 hours (MT50-24), ≥ 6 U of PRBCs in 6 hours (MT6-6), ≥ 10 U of PRBCs in 6 hours (MT10-6), a combination of MT10-24 plus MT6-6 (MTcombi), ≥ 5 U of PRBC in 4 hours (MT5-4), ≥ 4 U of PRBC in 1 hour (MT4-1), and the critical administration threshold (CAT) which is 3 U of PRBCs in 1 hour. The operative characteristics were calculated for each definition. Multiorgan failure was defined as a sequential organ failure assessment (SOFA) score of ≥ 6 points. Results: We included 394 subjects. A total of 266 (67%) received at least 1 unit of PRBCs in the first 24 hours, from which trauma mechanism was penetrating in 84.6%; 86.8% were male, with a median [interquartile range (IQR)] age of 29 (22–38) years and injury severity score (ISS) of 25 (25–29). A positive ABC score for massive transfusion score was positive in 87.2%. Sensitivity and specificity were as follows: multiorgan failure: MT10-24 18.6% and 98.2%, MT6-6 34.3% and 91.3%, MTcombi 38.2% and 91.3%, MT5-4 38.2% and 92.2%, and MT4-1 48% and 78.4%. Mortality: MT10-24 40.6% and 92.2%, MT6-6 62.7% and 82.6%, MTcombi 64.4% and 80.6%, MT5-4 61% and 81.1% and MT4-1 71.1% and 68.6%. Conclusion: All definitions showed an association with a higher risk of mortality and MOF, generally with low sensitivity but high specificity. The MT definition of ≥ 10 PRBCs in 24 hours should be revised.