ASA = American Society of Anesthesiology
ASA class refers to the risks in case of anestesiology

E.g.:

"The following preoperative variables were analyzed: indication for colostomy fashioning; age; gender; American Society of Anesthesiology (ASA) class; presence of cardiac, renal, or pulmonary dysfunctions; presence of diabetes mellitus; and immunosuppression. The occurrence of adverse outcome, as evidenced by postoperative morbidity and mortality, was used as the main outcome measure. Complications occurred in 49 patients (31.6%), including 1.3 per cent mortality. There was a trend of increasing morbidity with increasing ASA class."

"In 62% of cases the patients were in class ASA III and IV at high surgical risk (26 patients had been refused traditional surgery)."

HTH,

Serge L.