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Septic shock is a medical condition as a result of severe infection and sepsis, though the microbe may be systemic or localized to a particular site.〔 It can cause multiple organ dysfunction syndrome (formerly known as multiple organ failure) and death.〔 Its most common victims are children, immunocompromised individuals, and the elderly, as their immune systems cannot deal with infection as effectively as those of healthy adults. Frequently, patients suffering from septic shock are cared for in intensive care units. The mortality rate from septic shock is approximately 25–50%. ==Definition== Septic shock is a subclass of distributive shock, a condition in which abnormal distribution of blood flow in the smallest blood vessels results in inadequate blood supply to the body's tissues, resulting in ischemia and organ dysfunction. Septic shock refers specifically to distributive shock due to sepsis as a result of infection. Septic shock can be defined as sepsis-induced hypotension that persists despite treatment with intravenous fluids.〔 Low blood pressure reduces tissue perfusion pressure, causing the tissue hypoxia that is characteristic of shock. Cytokines released in a large scale inflammatory response result in massive vasodilation, increased capillary permeability, decreased systemic vascular resistance, and hypotension. Finally, in an attempt to offset decreased blood pressure, ventricular dilatation and myocardial dysfunction occur. Septic shock can be regarded as a stage of SIRS (Systemic Inflammatory Response Syndrome), in which sepsis, severe sepsis and multiple organ dysfunction syndrome (MODS) represent different stages of a pathophysiological process. If an organism cannot cope with an infection, it may lead to a systemic response - sepsis, which may further progress to severe sepsis, septic shock, organ failure, and eventually result in death. According to current guidelines, requirements for diagnosis with sepsis are "the presence (probable or documented) of infection together with systemic manifestations of infection".〔 These manifestations may include: *Tachypnea (high respiratory rate), which is defined as more than 20 breaths per minute, or when testing blood gas, a less than 32 mmHg, which signifies hyperventilation. *White blood cell count either significantly low, (< 4000 cells/mm3) or elevated (> 12000 cells/mm3). *Tachycardia (rapid heart rate), which in sepsis is defined as a rate greater than 90 beats per minute. *Altered body temperature: Fever > or hypothermia < Documented evidence of infection, may include positive blood culture, signs of pneumonia on chest x-ray, or other radiologic or laboratory evidence of infection. Signs of end-organ dysfunction are present in septic shock, including kidney failure, liver dysfunction, changes in mental status, or elevated serum lactate. Septic shock is diagnosed if there is refractory hypotension (low blood pressure that does not respond to treatment). This means that intravenous fluid administration alone is not enough to maintain a patient's blood pressure. Diagnosis of sepsis-induced hypotension is made when systolic blood pressure is less than 90mm Hg, a mean arterial pressure (MAP) is less than 70 mm Hg, or a systolic blood pressure decreases 40 mm Hg or more without other causes for hypotension.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「septic shock」の詳細全文を読む スポンサード リンク
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