Base deficit has frequently been utilized as an informal adjunct in the initial evaluation of trauma patients to assess the extent of their physiologic derangements. However, the current Advanced Trauma Life Support (ATLS) classification system for hypovolemic shock does not include base-deficit measurements and relies primarily on alterations in vital signs (heart rate, systolic blood pressure) and mental status (Glasgow Coma Scale) to estimate blood loss. The authors of this paper propose that the current ATLS system may not accurately reflect the degree of hypovolemic shock in many patients and that base-deficit measurements should be used in its place. The proposed system showed a greater correlation with transfusion requirements, need for massive transfusion, and mortality when compared with the ATLS classification system. Based on these findings, base-deficit measurement should be strongly considered during the initial trauma evaluation to identify the presence of hypovolemic shock and to guide blood product administration
