We will supply ICU physicians with a commonly used nerve stimulator (Stimuplex HNS 12, B.Braun, Germany) to attach to the needle-catheter assembly used to make the first insertion into the trachea. The nerve stimulator will be connected to a current meter, and a ground electrode will be attached to the body. When the needle tip is in contact with body tissue (i.e., tracheal wall), the electrical circuit will be closed, producing a reading of 1.0 mA on the current reader. Suspension of the needle tip in the airway will interrupt the circuit, producing a reading of 0.0 mA. In addition, an audible signal built into the nerve stimulator will alert the user to a change in current, warning that the needle tip has advanced too far and is in contact with the posterior or lateral tracheal wall.