AVTAA

1003 Felton Lane
Auburn, al 36830

(509)338-5205

www.avtaa-vts.org

American Society of Anesthesiologists (ASA) Physical Status Scale
  
Class I
 
Minimal Risk 
Normal healthy animal, no underlying disease 
Working Definition:  "Young, healthy patient for elective procedure."

Class II
 
Slight risk, minor disease present 
Animal with slight to mild systemic disturbance, animal able to compensate 
Examples:  neonate or geriatric animals, obesity
Working Definition:  "Healthy patient that needs a procedure."
 
Class III
 
Moderate risk, obvious disease present 
Animal with moderate systemic disease or disturbances
Examples:  anemia, moderate dehydration, fever, low-grade heart murmur or cardiac disease, emaciation
Working Definition:  "Systemic disease complicates anesthesia."
 
Class IV
 
High risk, significantly compromised by disease 
Animals with preexisting systemic disease or disturbances of a severe nature  
Examples:  severe dehydration, shock, uremia, toxemia, high fever, uncompensated heart disease, uncompensated diabetes, pulmonary disease 
Working Definition:  "Systemic disease jeopardizes anesthesia."
 
Class V
 
Extreme risk, moribund 
Surgery often performed in desperation on animal with life threatening systemic disease 
Examples: advanced systemic disease or condition (e.g. cardiac failure, renal failure, hepatic failure, cerebral insult, end stage endocrine disease, etc), uncompensated shock, severe trauma, terminal malignancy or infection that is a constant threat to life
Working definition:  "Patient will likely die with or without the procedure"
"E" denotes emergency and can be assigned to any class