- ASA 1 patients (normal, healthy patients) can climb one flight of stairs or walk two level city blocks without having to pause because of shortness of breath, undue fatigue, or chest pain.
- ASA 2 patients can climb one flight of stairs or walk two level city blocks without distress but must stop once they complete either task because of distress. Patients with heart failure most likely experience shortness of breath or undue fatigue.
- ASA 3 patients can climb one flight of stairs or walk two city blocks but must stop and rest before completing the task because of distress.
- ASA 4 patients cannot negotiate a flight of stairs or walk two level city blocks because of shortness of breath or undue fatigue present at rest.
- ASA 1: The patient does not experience dyspnea or undue fatigue with normal exertion.
- Comment: If all items of the medical history are negative, this patient may be considered normal and healthy. No special modifications in dental treatment are indicated. Patients with heart failure are not ASA 1 risks.
- ASA 2: The patient experiences mild dyspnea or fatigue during exertion.
- Comment: As with the ASA 1 patient, the ASA 2 patient may be managed normally if the remainder of their medical history and physical examination prove to be noncontributory. In addition, use of the stress reduction protocol should be considered if any physical or psychological stress is evident or anticipated.
- ASA 3: The patient experiences dyspnea or undue fatigue with normal activities.
- Comment: This patient is comfortable at rest in any position but may demonstrate a tendency toward orthopnea and have a history of paroxysmal nocturnal dyspnea. The ASA 3 patient with heart failure is at increased risk during dental treatment. Before starting any treatment, medical consultation and use of the stress reduction protocol and other specific treatment modifications should be given serious consideration.
- ASA 4: The patient experiences dyspnea, orthopnea, and undue fatigue at all times.
- Comment: The ASA 4 patient represents a significant risk. Even at rest this patient’s heart cannot meet the body’s metabolic requirements. Any degree of stress further increasing metabolic demand may exacerbate the condition and possibly provoke acute pulmonary edema. Invasive dental care should be withheld for all elective procedures until the patient’s cardiovascular status improves or is controlled. Dental emergencies (e.g., pain or infection) should be managed noninvasively, with medication, if at all possible. If physical intervention becomes necessary, this patient should be treated in a controlled environment, such as in a hospital dental clinic, and be under a physician’s care before, during, and immediately following the dental procedure.