Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. That definition matters more than it looks. It tells you that the danger is not the organism itself but what the body does in response to it, and it tells you that once organ dysfunction has appeared, the patient has already crossed out of "infection" and into a time-critical emergency. Septic shock is the subset of sepsis in which circulatory, cellular and metabolic abnormalities are severe enough to substantially increase mortality. Clinically it is the patient who still has hypotension requiring vasopressors to keep a mean arterial pressure of 65 mmHg or above, plus a lactate above 18.0 mg/dL, after adequate fluid resuscitation. For the RN this is one of the highest-yield topics on the exam and one of the highest-stakes at the bedside, because sepsis is a recognition problem far more often than it is a treatment problem. The therapies are protocolized and prescribed. What is not protocolized is the nurse noticing that a patient with a known infection has become slightly confused, is breathing at...