Is the Arterial Anastomosis Time a Key Predictor of Free Flap Failure in Oncological Head and Neck Reconstruction? A Prospective Cohort Study - Cristina Cárdenas Serres; Fernando Almeida Parra; Álvaro Ranz Colio; Ángela Bueno de Vicente; Patricia de Leyva Moreno; Verónica de Prado Mendoza; Jorge Nuñez Paredes; Manuel Picón Molina; Julio Acero Sanz (Journal of Clinical Medicine, 2026)