Which statement correctly describes ASA 4?

• A. A normal healthy patient
• B. A patient with mild systemic disease
• C. A patient with severe systemic disease that is a constant threat to life
• D. A moribund patient not expected to survive

Answer: (C)

ASA 4 describes a patient with severe systemic disease that is a constant threat to life. This means the illness is so serious that the patient’s stability is perpetually at risk, and anesthesia or even minor stress could trigger life-threatening events. It is more critical than ASA III (severe systemic disease not constantly life-threatening) and far from ASA I or II (healthy or only mild disease). It’s also distinct from ASA V, which is a moribund patient not expected to survive without the operation. So the description of a severe systemic disease that is a constant threat to life best matches ASA 4.