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Abstract The recognition, assessment and management of hypovolemic shock still remain an important task during initial trauma assessment. Recently, we have questioned the validity of the Advanced Trauma Life Support (ATLS) classification of hypovolemic shock by demonstrating that the suggested combination of heart rate, systolic blood pressure and Glasgow Coma Scale displays substantial deficits in reflecting clinical reality. Some studies were done to introduce and validate a new classification of hypovolemic shock based upon base deficit (BD) at emergency department (ED) arrival showed that base deficit may be superior to the current ATLS classification of hypovolemic shock in identifying the presence of hypovolemic shock and in risk stratifying patients in need of early blood product transfusion. The American College of Surgeons has defined in its training program Advanced Trauma Life Support (ATLS) four classes of hypovolemic shock. This classification is based upon an estimated blood loss in percent together with corresponding vital signs , For each class ATLS allocates therapeutic recommendations (for example, the administration of intravenous fluids and blood products) . Recently, the clinical validity of the ATLS classification of hypovolemic shock has been questioned by two analyses independently from each other on two large-scale trauma databases: the TARN (Trauma Audit and Research Network) registry and the Trauma Register DGU®, which had consisted of more than 140,000 trauma patients , According to both analyses, ATLS seems (a) to overestimate the degree of tachycardia associated with hypotension and (b) to underestimate mental disability in the presence of hypovolemic shock 113 These observations and conclusions prompted to develop an alternative approach for the early assessment of hypovolemic shock in the emergency department (ED). Several studies have already identified worsening base deficit (BD) as an indicator for increased transfusion requirement The base deficit is defined as the amount of base (in millimoles) needed to titrate one liter of whole blood to a PH of 7.40 at temperature of 37c and PCO2=40mm Hg, the normal range for base deficit is +2 to -2 mmol\L, in the injured or bleeding patient an elevated base deficit is an indicator of global tissue acidosis from impaired oxygenation . BD has been associated with increased mortality, intensive care unit (ICU) and in-hospital lengths of stay, and a higher incidence of shock-related complications such as acute respiratory distress syndrome , renal failure, hemocoagulative disorders, and multiorgan failure (MOF) . A lot of trauma scoring systems such as EMTRAS , TASH score , BIG score depends on BD as one of the parameters used to assess the condition of the patient. Monitoring of BD has also been suggested as an indicator and monitoring parameter for the success of resuscitation efforts, However a lot of objections arise now against considering BD the best end point of resuscitation , as the body response to regenerate HCO3 after resuscitation is relatively slow & there’s some medical interventions during resuscitation that can influence the BD, the BD can be assessed in a fast and easy manner and therefore is available within minutes after admission to the ED. |