Table 1.

Operative procedures categorized according to the magnitude of the surgery.

Major 1	Abdominal aortic aneurysm repair, panproctocolectomy,liver resection
Major 2	Right hemicolectomy, sigmoidectomy,thyroidectomy, mastectomy
Intermediate	Appendicetomy, hernia repair, varicoseveins surgery
Minor	Angiography, excision of moles, colonoscopy