Final answer:
Severe sepsis can develop during an encounter that is not present on admission as a result of an infection spreading and causing a systemic inflammatory response. Without prompt treatment, it can lead to septic shock, characterized by a significant drop in blood pressure, multiple organ failure, and high mortality.
Step-by-step explanation:
Severe sepsis develops during an encounter that is not present on admission when an initial localized infection spreads and results in a systemic inflammatory response, ultimately leading to widespread tissue damage and organ dysfunction. Situations such as puerperal sepsis following childbirth and infections from various sources (e.g., bacterial pneumonia, intra-abdominal infections, or urinary tract infections) can progress to sepsis if not promptly treated. The systemic inflammatory response syndrome (SIRS) can evolve into sepsis, characterized by excessive cytokine production causing fever, vasodilation, and edema. In severe cases, this can further progress to septic shock, which involves a perilous drop in blood pressure, blood clot formation, multiple organ failure, and potentially death. Therapies to combat sepsis and septic shock include aggressive antibiotic treatment, anti-inflammatory drugs, and in some situations, medications like drotrecogin-a.