☝️ ASA Physical Status (ASA-PS): The Preop “Common Language”

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Contents

♦️Introduction

ASA-PS appears on every preoperative anesthesia note and in most OR information systems. It’s the most widely used “shorthand” to communicate baseline physiologic status before surgery—useful for the whole perioperative team.

♦️What is “ASA”?🤔

“ASA” stands for the American Society of Anesthesiologists. The ASA introduced the Physical Status (PS) Classification to standardize how we describe patients’ pre-anesthesia comorbidities. (Japanese Society of Anesthesiologists = JSA.)
The statement with official definitions and example cases is maintained by the ASA.

🔗 American Society of Anesthesiologists

♦️ How the scale is used

ASA-PS has six classes; “E” is appended for emergency cases.

🔗 Statement on ASA Physical Status Classification System

🔷 ASA-PS1：“Totally healthy, feeling great!” 💪

Basically no medical problems; a normal healthy patient. This is the easiest group for anesthesia management.😊

🔷 ASA-PS 2：Got some medical issues, but basically doing fine! 🙂

A patient with mild systemic disease, well controlled, and no limitation in daily activities. Basically, these patients don’t require us to be overly concerned from an anesthesia standpoint.

controlled hypertension or diabetes,
obesity (not morbid),
current smokers without respiratory symptoms
well-compensated chronic conditions

👉 The definition of ASA II is broad. Some propose splitting it into “2a / 2b” for patients who are nearly healthy vs. those needing extra caution (Daabiss, 2011). Although not official, it can help communication. Institutions often provide concrete local examples to improve inter-rater agreement.

🔷 ASA-PS 3：Their health problems are really slowing them down… 😓

A patient with severe systemic disease that limits daily activity.

poorly controlled hypertension or diabetes (For diabetes, the presence of complications (nephropathy, retinopathy, neuropathy, etc.) puts the patient into ASA III)
morbid obesity,
pacemaker,
severe hepatic impairment,
dialysis,
ischemic heart disease,
valvular heart disease with dysfunction.

👉 These cases aren’t always obvious on first glance. Anesthesiologists must identify key risk factors and manage carefully to prevent perioperative complications.

🔷 ASA-PS 4：This is life-threatening… things look rough. 🚨

It’s obvious to everyone that the patient is critically ill. A patient with severe systemic disease that is a constant threat to life.

recent myocardial infarction
severe valvular disease
decompensated heart failure
shock
sepsis
Typical scenarios: emergency CABG, strangulated bowel, perforated viscus requiring urgent surgery.

👉 Intraoperative hemodynamic control is usually very challenging.

🔷 ASA-PS 5：Hanging by a thread… surgery is the only chance, but odds are bad. 💔

A moribund patient who will not survive without the operation, and may not survive even with it.

ruptured aortic aneurysm,
severe polytrauma,
massive intracranial hemorrhage,
ECMO-dependent cardiac/respiratory failure,
ischemic bowel with necrosis,
advanced liver failure,
multiple organ failure.

👉 These are extremely difficult cases for anesthesia, surgery, and the perioperative team.

🔷 ASA-PS 6：Brain-dead organ donor 🧠🫀

A declared brain-dead patient whose organs are being removed for donation.

⚠️ Gray zones and inter-rater differences

ASA I vs II, or III vs IV are usually clear. But ASA II vs III is often debated: some anesthesiologists rate an elderly but active patient with comorbidities as II, others as III (considering reduced physiologic reserve).

ASA-PS does not directly affect billing, but it’s a mandatory part of preop assessment and serves as a common language for the surgical team to share risk. The usual practice: if in doubt, lean toward the higher class to ensure safety. 🤗

ASA II vs III is where many disagreements occur in practice. Surveys and cohort studies show only moderate inter-rater reliability overall; agreement improves when raters use the official ASA examples and local, institution-specific examples. PubMed+2PubMed+2
Because ASA II spans a wide “mild disease” range, some authors have suggested subdividing lower classes (e.g., I/II into “a” and “b”) to better express nuance. This is not part of the official ASA system, but it has been explored in the literature. PMC
Use the ASA examples (and your department’s example list) to harmonize ratings between preop clinic and day-of-surgery. Quality-improvement work shows this improves agreement. BioMed Central
When in doubt—and especially for team communication—clinicians often err toward the higher class and document the rationale.

📝 Summary : Take Home Points

ASA-PS = common language, not a risk calculator; pair it with procedure and patient-specific risk tools.
Know the official examples—that’s the fastest way to reduce II vs III disagreements across the perioperative team.
“E” matters: always add it for emergencies (e.g., 3E).

📚 References & Further reading

American Society of Anesthesiologists. Statement on ASA Physical Status Classification System (official definitions and examples). Dec 13, 2020. asahq.org+1
Daabiss M. American Society of Anaesthesiologists physical status classification. Indian J Anaesth. 2011;55(2):111-115. (Open-access review; discusses proposals such as subdividing lower classes.) PMC
Sankar A, et al. Reliability of the American Society of Anesthesiologists physical status scale in clinical practice. Br J Anaesth. 2014;113(3):424-432. (Moderate inter-rater reliability in practice.) PubMed
Abouleish AE, et al. Improving agreement of ASA physical status class by adding institutional-specific and ASA-approved examples. Perioperative Medicine. 2020;9:34. (Open access QI project.) BioMed Central
Cleveland Clinic. ASA Physical Status Classification System (patient-facing explainer reinforcing “not a sole predictor”). Cleveland Clinic

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