Preliminary data from patients having vascular surgery show that those with diabetes have longer hospital stays, more frequent wound infections, and are more likely to require a return to the operating room when compared to patients without diabetes. In particular, insulin-treated patients have even greater peri-operative complications than non-insulin treated patients with diabetes. However, these data also suggest that a clinical trial to test the hypothesis that pre-operative intensive management has significant impact on peri-operative complications would require a very large number of participants to have adequate power.