anesthesia patients, classification of, a system developed by the American Society of Anesthesiologists used to classify patients within six categories defined by physical health status, regardless of whether the health problems are related to the condition requiring anesthesia. Class I includes patients who are healthy and who are without organic, physiological, biochemical, or psychiatric problems. Class II includes patients who have mild to moderate systemic disease that may be controlled by medications and that does not limit activity, such as anemia, mild diabetes, moderate hypertension, obesity, or chronic bronchitis. Class III includes patients who have significant systemic disturbances or disease that limits their activity. Class IV includes patients who have severe systemic disease that is a constant threat to life. Class V includes the moribund patient who is not expected to survive more than 24 hours with or without surgical intervention, such as a person in shock with a ruptured abdominal aneurysm or a massive pulmonary embolus. Class VI includes brain-dead patients who are undergoing organ harvest for donation. The letter E is added to the Roman numeral to indicate an emergency procedure that may preclude typical anesthesia preparation, such as nothing-by-mouth status.
