An animal model for pharyngocutaneous fistulas

Postoperative pharyngocutaneous fistula is not an uncommon complication. Although the frequency of postoperative fistulae has decreased with the use of perioperative broad-spectrum antibiotics, it remains a complication with significant morbidity and expense. We present an animal model for postoperative pharyngocutaneous fistulae based on increasing wound tension. The New Zealand white rabbit was used to assess the rate of wound breakdown in the thyrohyoid membrane. The animals were assigned to one of seven groups according to the width of tissue resected. After tissue resection, the pharyngeal wounds were repaired, as were the overlying skin wounds. Animals were monitored postoperatively up to 14 days, at which time they were killed and underwent autopsy. Statistically significant results were achieved that demonstrate an increasing incidence of pharyngeal wound breakdown associated with increasing width of tissue resected and, therefore, closure tension. The procedure and results will be presented in detail. We propose that this model may be used to assess postoperative wounds as well as substances or methods touted as promoters of wound healing.