Regarding ASA Physical Status Classification, all of the following statements are correct EXCEPT:

## ASA Physical Status Classification Overview The ASA Physical Status (PS) classification is a standardized system used to stratify preoperative risk and guide anesthetic management decisions. ### ASA PS Categories — Correct Definitions | ASA PS | Definition | Perioperative Mortality Risk | Examples | |--------|-----------|------------------------------|----------| | I | Healthy patient, no systemic disease | ~0.1% | Young, fit, no comorbidities | | II | Mild systemic disease, no functional limitation | ~0.4% | Well-controlled HTN, DM, mild asthma | | III | Severe systemic disease, functional limitation but not incapacitating | ~1.8% | Poorly controlled HTN, CAD, moderate COPD | | IV | Incapacitating systemic disease, constant threat to life | ~7.8% | Unstable angina, severe cardiac/renal/hepatic disease | | V | Moribund patient, not expected to survive 24 hrs without surgery | ~9.4% | Ruptured AAA, massive MI, septic shock | | VI | Brain-dead patient (organ donor) | N/A | Declared brain death | ### Analysis of the Options **Key Point:** The distinction between ASA PS IV and ASA PS V is critical: - **ASA PS IV:** Incapacitating disease that is a **constant threat to life** but patient is expected to survive with surgery - **ASA PS V:** Moribund patient **not expected to survive 24 hours without surgery** (even with surgery, survival is unlikely) The stem option stating "ASA PS IV includes patients with incapacitating systemic disease that is a constant threat to life and requires emergency surgery" is **INCORRECT** because: 1. ASA PS IV does NOT require emergency surgery — these patients have severe disease but are stable enough for elective procedures 2. The phrase "requires emergency surgery" is the defining feature of ASA PS V, not PS IV 3. ASA PS IV patients may undergo elective surgery; ASA PS V patients require urgent/emergency intervention **High-Yield:** The key differentiator is **urgency and expected survival**: - PS IV = severe but can wait for elective surgery - PS V = moribund, cannot wait, emergency only ### Clinical Pearl **Warning:** A common exam trap is confusing PS IV with PS V. Remember: PS IV has a "constant threat" but is not immediately life-threatening; PS V is moribund and unlikely to survive even with surgery. ### Mnemonic **ASPS Classification Severity:** **H-M-S-I-M-B** - **H**ealthy (PS I) - **M**ild disease (PS II) - **S**evere disease (PS III) - **I**ncapacitating disease (PS IV) - **M**oribund (PS V) - **B**rain-dead (PS VI) [cite:Miller's Anesthesia 8e Ch 27]