criticalillness

Critical illness is a medical condition characterized by life-threatening failure or dysfunction of one or more organ systems in acutely ill patients, typically requiring admission to an intensive care unit for advanced monitoring and support. It encompasses severe infections, trauma, major surgical complications, cardiovascular or respiratory collapse, and other acute illnesses. Diagnosis is largely clinical and based on the need for organ-support modalities rather than a single laboratory value.

Common features include rapid deterioration in mental status or physiologic stability, the need for mechanical ventilation, hemodynamic support with vasopressors or inotropes, and sometimes renal replacement therapy. Management focuses on treating the underlying cause while supporting organ function through airway management, ventilation strategies, circulatory support, infection control, nutrition, and prevention of complications such as delirium, bedsores, and muscle wasting. Multidisciplinary teams in an intensive care setting coordinate care and decision-making, including considerations of prognosis and goals of care.

Outcomes vary widely by illness type, comorbidities, and timely access to care. Mortality remains substantial in many categories, but survival has improved with advances in critical care. After discharge, many patients experience lingering physical, cognitive, or emotional deficits known as post-intensive care syndrome, and recovery can be prolonged and require rehabilitation and social support.

Critical illness also raises ethical and policy issues, including resource allocation, triage during surges, and the alignment of treatment with patient preferences and advance directives. Note that in non-medical contexts, critical illness may refer to insurance products that provide benefits on diagnosis of specified conditions; this article uses the medical meaning.