<prompt> Maximum AP diameter of trachea in male and female are27 mm and 25 mm25 mm and 23 mm25 mm and 21 mm20 mm and 15 mm  <response>: Trachea: - Trachea is a flexible tube that extends from veebral level C6 in the lower neck to veebral level T 4 5 in the mediastinum where it bifurcates into a right and a left main bronchus. Measurement of trachea: - Parameters Average Minimum Maximum A - P diameter mm Male Female Male Female Male Female 18.82 13.25 10.15 10.72 22.92 17.25 Transverse diameter 16.30 14.92 11.02 10.57 19.98 17.22 