Abstract: The invention relates to an endotracheal tube (1), usable in dilating percutaneous tracheostomy operations and comprising a tubular body (10) whose distal end, to be inserted in trachea, is provided with means (3) suitable to emit a light radiation for determining a transcutaneous illumination and with variable volume means (2), integral to said tube (1) and suitable to vary the total diameter of the tube, that is its encumbrance in the lumen of the trachea; tube (1) characterized in that said variable volume means (2) are shaped and/or positioned so that their expansion maintains said means (3) suitable to emit a radiation light substantially near the tracheal wall (P), that is in a position in which the means (3) are disposed substantially in contact with a wall (P) of the same trachea.