A 68-year-old woman with a history of myocardial infarction 6 months ago, currently on dual antiplatelet therapy, presents for elective hip arthroplasty. Which of the following statements about her ASA Physical Status Classification is NOT true?

Explanation

## ASA Physical Status Classification: Core Principle **Key Point:** ASA PS classification is determined **exclusively by the patient's medical status**, not by the type, urgency, or invasiveness of the planned surgery. This is a fundamental principle that is frequently tested in NEET PG. ## Analysis of This Patient's ASA PS A 68-year-old with: - History of myocardial infarction (6 months prior) - Currently on dual antiplatelet therapy - Undergoing elective hip arthroplasty This patient has **severe systemic disease** (coronary artery disease with prior MI) that may have **functional limitation** (reduced exercise tolerance, anginal symptoms). She would typically be classified as **ASA PS III** (or possibly PS IV if she has active cardiac symptoms or significant functional impairment). ## Why Option 4 Is Incorrect **High-Yield:** The ASA PS grade is **independent of surgical type and magnitude**. Whether the patient undergoes a minor procedure (e.g., skin biopsy) or a major procedure (e.g., hip arthroplasty), her underlying ASA PS remains the same. The type of surgery does NOT determine the ASA PS classification. This is a common misconception: students often confuse ASA PS (patient's medical status) with surgical risk stratification (which considers both patient factors AND surgical invasiveness). ## Comparison: What DOES and DOES NOT Affect ASA PS | Factor | Affects ASA PS? | Notes | | --- | --- | --- | | Patient's systemic disease burden | YES | Core determinant of ASA PS | | Functional limitation from disease | YES | Distinguishes PS II from PS III | | Type of surgery (major vs. minor) | NO | Does not change PS grade | | Urgency of surgery (elective vs. emergency) | NO | Only adds "E" suffix | | Medications (antiplatelet, anticoagulant) | NO | Do not change PS grade (though they affect perioperative risk) | | Anesthetic technique | NO | Does not change PS grade | **Clinical Pearl:** A healthy 30-year-old undergoing emergency open repair of a ruptured abdominal aortic aneurysm remains ASA PS I-E (healthy patient, emergency modifier). A 75-year-old with severe COPD undergoing a minor skin biopsy remains ASA PS III (severe disease, elective modifier would be PS III, not PS III-E). ## Mnemonic: ASA PS Determinants **"Medical Status Only"** — ASA PS reflects the patient's intrinsic medical condition. Surgery type, urgency, and medications do not change the grade; they are separate risk factors.