Botulinum toxin type A on cutaneous flap viability in diabetic and tobacco-exposed rats.

PURPOSE To investigate the effect of Botulinum toxin A (BoNTA) on skin flap viability in healthy, tobacco-exposed and diabetic rats. METHODS Ninety male Wistar rats (250-300g) were randomly divided into six groups: control+saline (C1), control+BoNTA (C2), tobacco-exposed+saline (T1), tobacco-exposed+BoNTA (T2) diabetes+saline (D1) and diabetes+BoNTA (D2). A dorsal cutaneous flap (3×10cm) was performed. Survival area and total area of the flaps were measured. Lumen diameter, external arterial diameter and lumen/wall thickness ratio were recorded. RESULTS Survival area increased in control group with BoNTA injection compared with control animals injected with saline (C2 x C1; 0.9±0.1 vs0.67±0.15, p= 0.001). A similar result was found in diabetes group injected with BontA (D2 x D1; 0.97±0.2 vs0.61±0.24, p=0.018). No difference was observed in skin flap viability in tobacco-exposed groups (T2 x T1; 0.74±0.24 vs 0.64±0.21, p=0.871). Lumen diameter (p= 0.004), external arterial diameter (p = 0.0046,) and lumen/wall thickness ratio (p= 0.003) were increased in diabetes+BoNTA-treated animals. This effect was not observed in control or in tobacco-exposed groups. CONCLUSIONS Botulinum toxin A increased skin flap viability in control and diabetic rats on the seventh post-operative day. Increased lumen diameter, external arterial diameter, and lumen/wall thickness ratio were observed in the diabetes+BoNTA group. BoNTA had no effect in the tobacco-exposed group on the seventh postoperative day.