Shock States Comparison

Shock is a life-threatening state of circulatory failure in which tissue oxygen delivery or utilization becomes inadequate to meet metabolic demands. The cells, not the blood pressure cuff, define shock. A patient can have a normal blood pressure and still be in shock, and a patient can have a low blood pressure and still be perfusing adequately. Shock may occur before hypotension develops. The four major categories are compared side by side so that you can name the likely mechanism at the bedside, and then choose the treatment that fits it: 1. Hypovolemic shock, including hemorrhagic shock. 2. Cardiogenic shock. 3. Distributive shock, which includes septic, anaphylactic and neurogenic shock. 4. Obstructive shock, which includes cardiac tamponade, tension pneumothorax and high-risk pulmonary embolism. The comparison matters because the first treatment that helps one category can harm another. Volume rescues a bleeding patient and can drown a patient whose pump has failed. Epinephrine reverses anaphylaxis and has no role in a bleeding patient. A chest decompression saves a patient with a tension pneumothorax and does nothing for sepsis. Clinical priority: identify...