ASA Physical Status Classification SYSTEM*

ASA I

Patients are considered to be normal and healthy. Patients are able to walk up one flight of stairs or two level city blocks without distress. Little or no anxiety. Little or no risk. This classification represents a "green flag" for treatment.

ASA II

Patients have mild to moderate systemic disease or are healthy ASA I patients who demonstrate a more extreme anxiety and fear toward dentistry. Patients are able to walk up one flight of stairs or two level city blocks, but will have to stop after completion of the exercise because of distress. Minimal risk during treatment. This classification represents a "yellow flag" for treatment. Examples: History of well-controlled disease states including non-insulin dependent diabetes, prehypertension, epilepsy, asthma, or thyroid conditions; ASA I with a respiratory condition, pregnancy, and/or active allergies. May need medical consultation.

Note: Patients who demonstrate a more extreme anxiety and fear toward dentistry have a baseline of ASA II even before their medical history is considered; that situation raises the classification system.

ASA III

Patients have severe systemic disease that limits activity, but is not incapacitating. Patients are able to walk up one flight of stairs or two level city blocks, but will have to stop enroute because of distress. If dental care is indicated, stress reduction protocol and other treatment modifications are indicated. This classification represents a "yellow flag" for treatment. Examples: History of angina pectoris, myocardial infarction, or cerebrovascular accident, congestive heart failure over six months ago, slight chronic obstructive pulmonary disease, and controlled insulin dependent diabetes or hypertension. Will need medical consultation.

ASA IV

Patients have severe systemic disease that limits activity and is a constant threat to life. Patients are unable to walk up one flight of stairs or two level city blocks. Distress is present even at rest. Patients pose significant risk since patients in this category have a severe medical problem of greater importance to the patient than the planned dental treatment. Whenever possible, elective dental care should be postponed until such time as the patient's medical condition has improved to at least an ASA III classification. This classification represents a "red flag" ‑ a warning flag indicating that the risk involved in treating the patient is too great to allow elective care to proceed. Examples: History of unstable angina pectoris, myocardial infarction or cerebrovascular accident within the last six months, severe congestive heart failure, moderate to severe chronic obstructive pulmonary disease, and uncontrolled diabetes, hypertension, epilepsy, or thyroid condition. If emergency treatment is needed, medical consultation is indicated.

ASA V

Patients are moribund and are not expected to survive more than 24 hours with or without an operation. These patients are almost always hospitalized, terminally ill patients. Elective dental treatment is definitely contraindicated; however, emergency care, in the realm of palliative treatment may be necessary. This classification represents a “red flag" for dental care and any care is done in a hospital situation.

ASA VI

Clinically dead patients being maintained for harvesting of organs.

ASA-E: Emergency operation of any variety (used to modify one of the above classifications, i.e., ASA III-E).

* Status can change as medical history changes; adapted by Margaret J. Fehrenbach, RDH, MS, from the American Society of Anesthesiologists, Medical Emergencies in the Dental Office (Malamed, Mosby, 2008), and included in Saunders Review of Dental Hygiene (Fehrenbach and Weiner, Elsevier, 2009).

Updated 1/2/2009