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Shock is a life‐threatening physiological state characterized by decreased tissue perfusion and end‐organ tissue dysfunction, and is a significant predictor for complications including death [1]. The presence of shock must be recognized and therapeutic interventions must be started early to prevent progression. Unfortunately, identification and treatment of shock in the out‐of‐hospital setting are fraught with many difficulties and potential pitfalls. Patient assessment is often limited by the challenging environment. The tools available for the diagnosis and treatment of shock in the field are limited. Even when shock is properly identified, the most appropriate management is often unknown or the subject of debate.

In the field, identification of shock relies primarily on recognition of signs and symptoms, including tachycardia, poor skin perfusion, and altered mental status. Note that hypotension, arbitrarily defined at a systolic blood pressure (sBP) of less than 90 mmHg, is not an adequate definition of shock and may not adequately reflect the onset of tissue hypoperfusion [2]. Unfortunately, the early stages of compensated shock, with only subtle alterations in physical findings, are easily overlooked or misinterpreted by clinicians. Physiological changes associated with age, pregnancy, or treatment for medical conditions such as beta‐blockers for hypertension, may also mask or alter the body’s compensatory responses. As a result, the patient with severe shock may present with near‐normal vital signs.