Effect Of Pentoxifylline, Aspirin, And Heparin On Skin Flap Survival And Bleeding Tendency In Rabbits

ABSTRACT

skin flap, which has been frequently used in the maxillofacial soft tissue defects, can be failed due to insufficient blood supply to the flap. To increase its survival rate,antithrombotic agents has been used. The agents have, however, been restrictly used because of their side effects,such as bleeding tendency or hematoma formation on the operation site. The present study aimed to the effect of pentoxifylline,aspirin,and heparin on the skin flap survival rate and bleeding tendency. Twelve adult white rabbits, weighing about 2.0 kg,were used.Five random skin flaps, which is 1mm thickness,were prepared on the dorsal surface of each rabbit by using 1.5 x 7.5 cm prefabricated template. The animals were divided into 4 groups on the basis of drugs used Control group, animals in which no drug was given (n=3); Pentoxifylline group, animals in which pentoxifylline was given intraorally (n=3); Aspirin group,animals in which aspirin was given intravenously (n=3), and Heparin group,animals in which heparin was given intravenously (n=3). On the 3rd and 7th day after operation, prothrombin time (PT) and activated partial thromboplastin time (aPTT)were measured to evaluate the bleeding tendency. The animals were sacrificed on the 7th day and the mean skin flap survival rate of each group was measured. The results obtained were as follows The skin flap survival rates of pentoxifylline (84.3 +/- 7.9%)and heparin (79.5 +/- 10.9%) groups were significantly increased, compared with control group (68.0 +/- 10.8%)(P<0.05).The survival rate of aspirin group (73.0 +/- 11.1%) was not increased. In bleeding tendency, the PT values were prolonged in heparin and aspirin groups at the 3rd day after operation (P<0.05), and prolonged in order of heparin group, aspirin group, and pentoxifylline group at the 7th day after operation. The aPPT values in heparin and aspirin groups were also prolonged at the 3rd day after operation (P<0.05), and prolonged in order of Aspirin group, Heparin group, and Pentoxifylline group at the 7th day after operation. These results suggest that pentoxifylline may be the most useful drug among three drugs to increase skin flap survival rate and less increase the bleeding tendency.