Conference Lectures

 IS IT TIME TO REVISE ASA PHYSICAL STATUS
Sujata Ghosh
Assistant Professor
Department of Anaesthesiology
Calcutta National Medical college
Kolkata

In 1940,the  American Society of Anaesthesiologists formed a committee headed by Drs.E.A.Rovenstine, Meyer Saklad, and Ivan B.Taylor,to standardize physical status categories for statistical studies  for hospital records so that uniform interpretation would be possible.
The original definition by Saklad et al was


CLASS
1

 

No organic pathology or patients in whom the pathological process is localized and does not cause any systemic disturbance or abnormality

CLASS
2

A moderate but definite systemic disturbance, caused either by the condition that is to be treated or surgical intervention or which is caused by other existing pathological processes, forms this group

 

CLASS
3

Severe systemic disturbance from any cause or causes. It is not possible to state an absolute measure of severity, as this is a matter of clinical judgment. The following examples are given as suggestions to help demonstrate the difference between this class and Class 2.

CLASS
4

Extreme systemic disorders which have already become an eminent threat to life regardless of the type of treatment. Because of their duration or nature there has already been damage to the organism that is irreversible. This class is intended to include only patients that are in an extremely poor physical state. There may not be much occasion to use this classification, but it should serve a purpose in separating the patient in very poor condition from others.

CLASS
5

Emergencies that would otherwise be graded in Class 1 or Class 2.

CLASS6

Emergencies that would otherwise be graded as Class 3 or Class 4.

 

In 1963 the American Society of Anesthesiologists (ASA) adopted the five-category physical status classification system; a sixth category was later added. These are:

  1. Healthy person.
  2. Mild systemic disease.
  3. Severe systemic disease.
  4. Severe systemic disease that is a constant threat to life.
  5. A moribund person who is not expected to survive without the operation.
  6. A declared brain-dead person whose organs are being removed for donor purposes.

If the surgery is an emergency, the physical status classification is followed by “E”
In 1974,minor rhetorical changes were made by the House of Delegates of the ASA and 5 classes were defined in their present state.
In 1978 Williams D.Owens et all tested the ASA Physical status for consistency by the use of a questionarre sent to 304 anaesthesiologists and found that only 59% of cases were rated consistently.He called for its revision in 1979 but even after 2 decades the change is yet to arrive.
After several suggestions by several authors, recently in 2006 , T Higashizawa, Y Koga. Modified ASA Physical Status (7 grades) May Be More Practical In Recent Use For Preoperative Risk Assessment. The Internet Journal of Anesthesiology. 2006 Volume 15 Number 1.has proposed a revised classification consisting of ,  grade 1a, 1b, 2a, 2b, 3, 4 and 5. Accordingly Reevaluation of ASA physical status (7-grade) can provide a better grading outcome for predicting the incidence of intra- and postoperative complications in surgical patients compared with the conventional ASA's. Guidelines.

                Till date there are no changes in ASA physical status in the ASA Relative Value Guide, which is published annually. Moderately severe diseases are not considered in the classification.There is also no definite guidelines for the placement of patients suffering from two or more diseases of varying severity.Often different anaesthesia providers assign different grades for the same patient.The coinage, systemic disease is controversial in that diseases  like heart attack,COPD, asthma, co-existing infections are local diseases with serious consequences.However they are not dealt with in ASA physical status.Anaesthesiologists are also unsure of the status of patients with intestinal perforation, head injury and RTA.
Age ,especially neonates and elderly,have no bearing on ASA PS.However it is well known that these age groups tolerate anaesthesia poorly even in the abscence of disease.So is the patients with morbid obesity.
Patients with malignancy have extensive systemic and local changes but there is no particular class assigned to these patients.
The ASA physical status is extensively used for cost re-imbersement. The utility of ASA physical status is its  simplicity and universality. It is the only
expression of the overall pre-operative condition which is widely recorded.In a broad perspective, the ASA physical status is a workable classification system which is more useful for the administratos and insurers. So a more elaborate and scientifically precise classification needs to be  adopted.