The Use of Botulinum Toxin to Prevent Anastomotic Thrombosis and Promote Flap Survival: A Bridge to Developing Clinical Studies.

[BACKGROUND] Despite the possibility of using botulinum toxin to improve perfusion and prevent vasospasm, only a few studies have examined the use of botulinum toxin in the setting of flap surgery and thrombosis, and the mechanisms have not been fully explained.

[OBJECTIVE] The primary objective of this study was to provide a comprehensive review of the effectiveness of botulinum toxin in anastomotic thrombosis prevention and surgical flap survival to determine the value of conducting large-scale human trials.

[METHODS] Using the SYRCLE and CAMRADES criteria, a systematic review was performed. PubMed, Medline, EmBase, and the Cochrane Library were searched for studies that met our eligibility criteria.

[RESULTS] Twenty studies were included in the final selection. A total of 397 subjects were included. Eighteen studies used botulinum toxin type A alone, one used botulinum toxin type B alone, and only one used both botulinum toxin type A and botulinum toxin type B. The most commonly used injection technique was a preoperative intradermal injection. The most common procedure performed was a pedicled flap with random pattern skin flaps (65%). The mean injection dose was 28.17 ± 49.21 IU, whereas the mean reported injection time for studies using animal models was 7.4 ± 6.84 days.

[CONCLUSIONS] Similar mechanisms demonstrated in animal models may be replicable in humans, allowing botulinum toxin to be used to prolong flap survival. However, many factors, such as optimal injection techniques, dosages, and long-term outcomes of botulinum use in flap surgery, need to be further assessed before applying this to clinical practice.