This study aimed to analyze laryngotracheal separation (LTS) outcomes and evaluate the efficacy of the evaluation criteria for prophylactic innominate artery transection (PIAT) in neurologically impaired patients.

67 patients who underwent LTS were reviewed. They were divided into three groups: patients without a tracheostomy tube (TT) (Group 1), patients with a TT but without PIAT (Group 2) and patients with TT and PIAT (Group 3). The length between the dorsal edge of the sternum and ventral edge of the vertebra (D-to-V), tracheal flattening ratio (TFR), and mediastinum-thoracic anteroposterior ratio (MTR), as evaluation criteria for PIAT based on the previous studies were measured.

62 patients [F/M = 25/37, Group 1 (n = 27), Group 2 (n = 29), and Group 3 (n = 6)] were analyzed. Three patients in Group 3 underwent PIAT after LTS due to intratracheal granuloma and minor bleeding. The TFR in Group 3 was significantly lower than that in Group 1 and 2 (p = 0.0236, 0.0054). The proportions of patients who met the criteria for PIAT were 5cases (8.06%) assessed by D-to-V, 21cases (33.87%) by TFR, and 37cases (59.68%) by MTR.

D-to-V would be the efficient criteria for PIAT and low TFR and MTR patients should be followed up carefully.