 Ultrasound that is performed before percutaneous procedure may be useful in preventing damage to para tracheal adjacent structures, and preventing high placement of the tube. The use of duplex sonography with real-time visualization of the needle path is done routinely in procedures such as central venous catheterization, and may improve the safety and accuracy of percutaneous tracheostomy without causing airway obstruction or hypercarbia. Feasibility of the procedure has been reviewed in an article by Rajajee et al . 