TABLE 1.

Dichotomized Perioperative Variables

	Positive Criteria
Diabetes	Non–insulin-dependent or insulin-dependent diabetes
Smoker	Cigarette smoking within the year before admission
Steroid	Intake of steroids and/or immunosuppressive medications for a chronic condition within 30 d before surgery
Weight loss	Weight loss greater than 10% of body weight within 6 mo before surgery
SIRS	SIRS within 48 hours before surgery
Sepsis	Septic shock within 48 h before surgery
BMI	Obese (>30 kg/m2)
Wound class	Contaminated or dirty/infected wound
Ventilator dependence	Need for ventilator assisted respiration in the 48 h before surgery
Ascites, congestive heart failure, COPD, dyspnea, hypertension	Conditions present within 30 d before the operation
Open wound	Open wound in the skin with or without infection
Disseminated cancer	Dissemination or metastasis of primary cancer within 1 y before surgery
Bleeding disorder	Documented chronic hematologic disorder or medication use that interferes with clotting
Acute renal failure	Present within 24 h before surgery
Dialysis	Dialysis at any point within the 2 wk before surgery
Transfusion	Documented events requiring at least 5 U of blood within the 72 h before surgery
ASA class	ASA class ≥3
LOS	Prolonged LOS defined by the fourth quartile (>12 d)
Age	Older (≥65 y)

COPD, chronic obstructive pulmonary disease; SIRS, systemic inflammatory response syndrome.