ASA Physical Status Classification System - American Society of Anesthesiologists (ASA)
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ASA Physical Status Classification System

  • Developed By: ASA House of Delegates/Executive Committee
  • Last Amended: October 15, 2014 (original approval: October 15, 2014)

Table 1: Current definitions (NO CHANGE) and Examples (NEW)

ASA PS Classification Definition Examples, including, but not limited to:
ASA I A normal healthy patient Healthy, non-smoking, no or minimal alcohol use
ASA II A patient with mild systemic disease Mild diseases only without substantive functional limitations. Examples include (but not limited to): current smoker, social alcohol drinker, pregnancy, obesity (30<BMI<40), well- controlled DM/HTN, mild lung disease
ASA III A patient with severe systemic disease Substantive functional limitations;
One or more moderate to severe diseases. Examples include (but not limited to): poorly controlled DM or HTN, COPD, morbid obesity (BMI ≥40), active hepatitis, alcohol dependence or abuse, implanted pacemaker, moderate reduction of ejection fraction, ESRD undergoing regularly scheduled dialysis, premature infant PCA < 60 weeks, history (>3 months) of MI, CVA, TIA, or CAD/stents.
ASA IV A patient with severe systemic disease that is a constant threat to life Examples include (but not limited to): recent (<3 months) MI, CVA, TIA, or CAD/stents, ongoing cardiac ischemia or severe valve dysfunction, severe reduction of ejection fraction, sepsis, DIC, ARD or ESRD not undergoing regularly scheduled dialysis
ASA V A moribund patient who is not expected to survive without the operation Examples include (but not limited to): ruptured abdominal/thoracic aneurysm, massive trauma, intracranial bleed with mass effect, ischemic bowel in the face of significant cardiac pathology or multiple organ/system dysfunction
ASA VI A declared brain-dead patient whose organs are being removed for donor purposes  
 *The addition of “E” denotes Emergency surgery:
(An emergency is defined as existing when delay in treatment of the patient would lead to a significant increase in the threat to life or body part)


Appendix 1

References related to use of the ASA PS Classification System

  1. Guidelines for the use of Sedasys by non-anesthesia trained proceduralist and nurse. 4
  2. American College of Surgeons’ proposed guidelines for care of pediatric surgical patients. 6 Journal of the American College of Surgeons, 2014;218:479-48
  3. Guidelines for local anesthesia cases in a major academic center. “Monitoring patients 8 receiving local anesthesia”, MGH, Perioperative Nursing, OR L. 16
  4. Office Based Procedure guidelines 10 ines/MQIC%202009%20Office-Based%20Surgery%20Guideline.pdf
  5. Preoperative testing guidelines. society-of-anesthesiologists/

Appendix 2

Selected References Addressing Inter-Rater Reliability of the ASA PS Classification System

  1. Owens WD, Felts JA, et al. ASA physical status classifications: A study of consistency of 19 ratings. Anesthesiology. 1978;49:239–43 (Editorial by Keats AS. The ASA Classification of 20 Physical Status – A Recapitulation. Anesthesiology 1978;49:233-6)
  2. Haynes SR, Lawler PG. An assessment of the consistency of ASA physical status 22 classification allocation. Anaesthesia. 1995;50:195-9
  3. Mak PH, Campbell RC et al. The ASA physical status classification: inter-observer 24 consistency. Anaesth Intensive Care 2002;30:633-40
  4. Aronson WL, McAuliffe MS, Miller K. Variability in the American Society of 26 Anesthesiologists Physical Status Classification Scale. AANA J. 2003;71:265–74
  5. Jacqueline R, Malvivya S et al. An assessment of interrater reliability of the ASA physical 28 status classification in pediatric surgical patients. Paediatr Anaesth 2006;16:928-31
  6. Burgoyne LL, Smeltzer MP. How well do pediatric anesthesiologists agree when assigning 30 ASA physical status classifications to their patients. Paediatr Anaesth 2007;17:956-62
  7. Bernard PA, Makin CE et al. Variability of ASA physical status class assignment among 32 pediatric sedation practitioners. Int J Adolesc Med Health 2009;21:213-20
  8. Cuvillon P, Nouvellon E et al. American Society of Anesthesiologists' physical status system: 34 a multicentre Francophone study to analyse reasons for classification disagreement. Eur J 35 Anaesthesiol 2011;28:742-7
  9. McMillan M, Brearley J. Assessment of the variation in American Society of 37 Anesthesiologists Physical Status Classification assignment in small animal anaesthesia. Vet 38 Anaesth Analg. 2013 May;40(3):229-36
  10. Sankar A, Johnson SR et al. Reliability of the American Society of Anesthesiologists physical 40 status scale in clinical practice. Br J Anaesth 2014 Apr 11 (epub ahead of print)

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