Comparison of the effects of troxerutin and heparinoid on flap necrosis.

We aimed to assess the effects of local troxerutin and heparinoid (HEP) treatments in a model of flap necrosis. Three groups of Wistar albino rats, each comprising 10 animals were used. A cranially based 6x3-cm full-thickness random-pattern skin flap was raised and sutured to the same area in each model. The control group was treated daily with normal saline, the second with topical HEP and the third with topical troxerutin. The amount of flap necrosis was measured in all groups by the end of the seventh day. Flap tissues were excised for histological analysis and evaluation of the expression of vascular endothelial growth factor (VEGF) levels. Assessment of the blood levels of nitric oxide was also performed in each animal by cardiac puncture. The mean area of flap necrosis was 110.6mm(2) in the control, 39.44 mm(2) in the troxerutin and 47.11 mm(2) in the heparinoid-treated rats. The treatment arms exhibited significant reduction in areas of flap necrosis, compared with the control group (p<0.001), but it was similar among treatment groups (p=0.60). The rates of fibroblast proliferation were decreased in control group as compared to HEP and troxerutin arms (p<0.001). The mean level of collagen density, collagen organisation, granulation tissue and demarcation were similar in all rats. Measurement of VEGF expression did not show any significant difference between the groups (p=0.30). Nitric oxide levels were significantly higher in control rats, as compared to treatment groups (p<0.0001), but were similar in treatment arms (p=0.45). Our results suggest that troxerutin and HEP effectively reduce the flap necrosis and improve flap survival. The observed effects might be due to their anti-oedematogenic, radical-scavenging, antioxidant effects and supportive activities on capillary permeability and transudation.