Time necessary for neovascularization of a tracheal segment by the sternohyoid muscle

INTRODUCTION: The reimplantation of a complete tracheal segment (CTS) as an autograft or homograft often results in total or partial necrosis of the C TS. However, previous experiments suggested that when the CTS is first vasc ularized by the sternohyoid muscle (SM) 21 days before the reimplantation, the CTS can be reimplanted without ischemia or stenosis. However, it is not clear if the CTS requires 21 days to attain full revascularization. GOAL: This study aims to ascertain the minimum time necessary for revascula rization of the 6 rings CTS by the SM allowing reimplantation free of ische mia. METHODS: Fifteen mongrel dogs, divided into 3 groups were submitted to 2 se quential surgical procedures. In the first procedure, a SM flap was used to envelop 6 rings CTS in all dogs. After periods of 21 days (group 1, n = 5) , 14 days (group 2, n = 5) and 7 days (group 3, n = 5), the compound flaps (CTS and SM) were neovascularized. Each CTS was transected and mobilized fr om the trachea and then replaced again in its original site, as an autoflap . RESULTS: After a period of at least 60 days, none of dogs presented any res piratory alteration. Macroscopic and microscopic analyses demonstrated adeq uate viability and no stenosis. CONCLUSION., Our findings suggest that it is possible to neovascularize the CTS using a SM flap within a period as short as 1 week.