What distinguishes ASA II from ASA III in the ASA physical status classification?

• A. ASA II is mild systemic disease without substantive functional limitations; ASA III is severe systemic disease that limits activity but is not incapacitating.
• B. ASA II has no systemic disease; ASA III has mild systemic disease.
• C. ASA II requires major risk preop labs; ASA III doesn't.
• D. ASA II is incapacitating disease; ASA III is unhealthy.

Answer: (A)

The main concept is how the ASA physical status classifies preoperative health based on how systemic disease affects daily function. The difference between the two levels is about functional impact. ASA II means mild systemic disease that does not substantively limit daily activities—you can go about usual tasks without meaningful restriction. ASA III means severe systemic disease that does limit activity, though the patient is not incapacitated and remains able to perform daily tasks with some effort. This reflects a higher baseline risk because the disease is more impactful on function and typically associated with greater perioperative risk. For example, someone with well-controlled conditions and no functional limitation fits ASA II, while someone with a significant systemic illness that impairs activity—but who is still ambulatory—fits ASA III.