What is the patient's American Society of Anesthesiologists (ASA) classification?

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ASA Classification Cannot Be Determined Without Patient Information

To assign an ASA classification, you must systematically assess the patient's physical health status and systemic disease burden—age alone is explicitly excluded as a criterion. 1, 2

ASA Classification Framework

The American Society of Anesthesiologists classification system ranges from ASA I through ASA VI based on the following criteria 1:

ASA I: Healthy Patient

  • No systemic disease
  • Nonsmoking status
  • No or minimal alcohol use 1

ASA II: Mild Systemic Disease

  • No substantive functional limitations
  • Examples include:
    • Current smoking
    • Social alcohol use
    • Pregnancy
    • Obesity (BMI 30-40 kg/m²)
    • Well-controlled diabetes or hypertension
    • Mild lung disease 1

ASA III: Severe Systemic Disease with Functional Limitations

  • Substantive functional limitations present
  • Examples include:
    • Poorly controlled diabetes or hypertension
    • COPD
    • Active hepatitis
    • Alcohol dependence
    • Implanted pacemaker
    • Moderate reduction of ejection fraction
    • Morbid obesity (BMI ≥40 kg/m²) 1, 3

ASA IV: Severe Systemic Disease as Constant Threat to Life

  • Life-threatening systemic disease 1

ASA V: Moribund Patient

  • Not expected to survive without the operation 1

ASA VI: Brain-Dead Organ Donor

  • Organs being removed for donation 1

Critical Assessment Points

When determining ASA class, you must evaluate 1, 2:

  • Presence of systemic disease (none = ASA I, mild = ASA II, severe with limitations = ASA III)
  • Severity and control of existing conditions (poorly controlled conditions elevate classification)
  • Functional limitations caused by disease states
  • Specific health factors: smoking, alcohol use, obesity, chronic conditions

Common Pitfall to Avoid

Do not automatically increase ASA class based solely on age—a 64-year-old patient's age does not by itself determine ASA classification. 1, 2 Focus instead on actual health status, comorbidities, and functional capacity. 2

Clinical Implications

  • ASA I-III patients are appropriate candidates for sedation by non-anesthesiologists 1
  • ASA III-IV patients require consultation with a senior anesthesiologist as far before surgery as possible for preoperative optimization 4
  • ASA IV-V patients may require an anesthesia specialist 1

To provide the patient's specific ASA classification, you need information about their systemic diseases, functional status, and control of chronic conditions—not demographic data alone.

References

Guideline

ASA Classification Guidelines

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

ASA Classification Principles

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Perioperative Management of ASA III Patients

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Research

The ASA classification and peri-operative risk.

Annals of the Royal College of Surgeons of England, 2011

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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