BACKGROUND: Aspirin and heparin are commonly given to patients undergoing microvascular procedures to increase flap survival and patency, yet there is scant information concerning the effect these flaps have on nonmicrovascular flaps. OBJECTIVE: The objective was to obtain baseline values concerning the effect of aspirin and heparin on the viability of standardized flap tissues. METHODS AND MATERIALS: One hundred rats were divided into five groups receiving high-dose aspirin, low-dose aspirin, high-dose aspirin in combination with heparin, and heparin alone and the final group were controls. The viability of the tissue was measured at 1 week by fluorescein florescence. RESULTS: There was significant improvement in flap survival in the high-dose aspirin and high-dose aspirin combination groups. CONCLUSIONS: It appears that high-dose aspirin increases survival of ischemic flap tissue irrespective of the presence of microvascular anastomosis and may be of clinical benefit in all flap surgery.