Variable	Definition
Hx of stroke/hemiplegia	A history of a cerebrovascular accident (embolic, thrombotic, or hemorrhagic) with or without persistent residual motor, sensory, or cognitive dysfunction. Acute or chronic neuromuscular injury resulting in total or partial paralysis or paresis (weakness) of one side of the body.
Hx of TIA	A history of focal neurologic deficits (e.g. numbness of an arm or amaurosis fugax) of sudden onset and brief duration (usually <30 minutes) that usually reflects dysfunction in a cerebral vascular distribution.
Hx of Angina or MI	A history of angina (pain or discomfort between the diaphragm and the mandible resulting from myocardial ischemia) or myocardial infarction (MI, a non-Q wave or a Q wave infarct in the six months prior to surgery) For patients on anti-anginal medications, only patients who had angina within one month prior to surgery are included.
Congestive Heart Failure	Newly diagnosed CHF within the previous 30 days or a diagnosis of chronic CHF with new signs or symptoms in the 30 days prior to surgery
Previous PCI	A percutaneous coronary intervention (PCI) at any time (including any attempted PCI). This includes either balloon dilatation or stent placement.
Previous Cardiac Surgery	Any major cardiac surgical procedures, includes coronary artery bypass graft surgery, valve replacement or repair, repair of atrial or ventricular septal defects, great thoracic vessel repair, cardiac transplant, left ventricular aneurysmectomy, insertion of left ventricular assist devices (LVAD), etc. Not include are pacemaker insertions or automatic implantable cardioverter defibrillator (AICD) insertions.
Diabetes Mellitus	Diabetes mellitus with oral agents or insulin. The treatment regimen of the patient’s chronic, long-term management.
Hypertension	Persistent elevation of systolic blood pressure > 140 mm Hg or a diastolic blood pressure > 90 mm Hg or requires an antihypertensive treatment (e.g., diuretics, beta blockers, ACE inhibitors, calcium channel blockers) at the time the patient is being considered as a candidate for surgery (which should be no longer than 30 days prior to surgery).
Current smoker	Current smoker (cigarettes) within one year.
Hx of smoking	If the patient has ever been a smoker, the total number of pack/years (number of packs of cigarettes smoked per day times the number of years the patient has smoked) of smoking for this patient is provided.
Alcohol use > 2 eh/day	The patient admits to drinking >2 ounces of hard liquor or > two 12 oz. cans of beer or > two 6 oz. glasses of wine per day in the two weeks prior to admission.
BMI	Body mass index, calculated as weight (kg) divided by height (m)2 <18.5 underweight, 18.5–24.9 normal weight, 25–29.9 overweight, 30–34.9 obese class I, 35–40 obese class II, ≥40 obese class III
Renal failure	Acute (steadily increasing azotemia [increase in BUN] and a rising creatinine of above 3 mg/dl < 24 h prior to surgery) or chronic renal failure requiring treatment with peritoneal dialysis, hemodialysis, hemofiltration, hemodiafiltration, or ultrafiltration within 2 weeks prior to surgery.
Hx of COPD	History of severe chronic obstructive pulmonary disease resulting in any one or more of the following: -Functional disability from COPD (e.g., dyspnea, inability to perform ADLs) -Hospitalization in the past for treatment of COPD -Requires chronic bronchodilator therapy with oral or inhaled agents. -An FEV1 of <75% of predicted on pulmonary function testing. Patients are not included whose only pulmonary disease is asthma, an acute and chronic inflammatory disease of the airways resulting in bronchospasm. Patients are not included with diffuse interstitial fibrosis or sarcoidosis.
Dyspnea	Difficult, painful, or labored breathing <30 days of surgery. Dyspnea may be symptomatic of numerous disorders that interfere with adequate ventilation or perfusion of the blood with oxygen
Steroid use	If a patient requires regular administration of oral or parenteral corticosteroid medications (e.g., Prednisone, Decadron) in the 30 days prior to surgery for a chronic medical condition (e.g., COPD, asthma, rheumatologic disease, rheumatoid arthritis, inflammatory bowel disease). Patients who only receive short course steroids (duration 10 days or less) in the 30 days prior to surgery are not included
Hx of revascularization for PVD	History of revascularization/amputation for peripheral vascular disease (PVD): any type of angioplasty (including stent placement) or revascularization procedure for atherosclerotic PVD (e.g., aorta-femoral, femoral-femoral, femoral-popliteal) or a patient who has had any type of amputation procedure for PVD (e.g., toe amputations, transmetatarsal amputations, below the knee or above the knee amputations). Patients who have had amputation for trauma or a resection of abdominal aortic aneurysms should not be included.
Restpain/gangrene	Rest pain is a more severe form of ischemic pain due to occlusive disease, which occurs at rest and is manifested as a severe, unrelenting pain aggravated by elevation and often preventing sleep. Gangrene is a marked skin discoloration and disruption indicative of death and decay of tissues in the extremities due to severe and prolonged ischemia. Patients included with ischemic ulceration and/or tissue loss related to peripheral vascular disease. Fournier’s gangrene are not included.
Functional status	Functional health status prior to surgery <30days. This variable focuses on the patient’s abilities to perform activities of daily living.
Emergency procedure	An emergency case is usually performed as soon as possible and no later than 12 hours after the patient has been admitted to the hospital or after the onset of related preoperative symptomatology.
ASA class > 3	The American Society of Anesthesiology (ASA) Physical Status Classification of the patient�s present physical condition on a scale from 1–5 as it appears on the anesthesia record. ASA 1 -Normal healthy patient ASA 2 -Patient with mild systemic disease ASA 3 -Patient with severe systemic disease ASA 4 -Patient with severe systemic disease that is a constant threat to life ASA 5 -Moribund patient who is not expected to survive without the operation.