To the Editor:—Several devices have been described for use when an endotracheal tube is exchanged in a patient with a compromised airway. These include the jet stylet and the fiberoptic bronchoscope. However, each of these methods is not always reliable when used alone. We describe a case in which the two techniques were combined for the exchange of an endotracheal tube in a patient with cervical spine instability.
A 73-yr-old man with metastatic prostate carcinoma presented with acute quadraparesis secondary to fracture of the odontoid process and C1-C2 instability. The endotracheal tube developed a cuff leak and required replacement. A medium-size tracheal tube exchanger (Sheridan, Argyle, NY) was placed through the original endotracheal tube. The exchanger was connected to a jet ventilation source via a 14-G intravenous catheter, and positive pressure ventilation was stopped briefly. Jet ventilation was tested to evaluate that it would provide adequate gas exchange. A fiberoptic bronchoscope (Olympus FL Tracheal Intubation Fiberscope-1 mm deflectable insertion tube, Lake Success, NY) was guided orally into the trachea around the deflated cuff of the original 8.0 endotracheal tube. When the carina was visualized with the fiberscope, the original endotracheal tube was removed. A new 7.5 endotracheal tube was threaded into the trachea over the fiberscope.
Many techniques of airway management have been used in cervical spine instability. Mask ventilation has been shown to move the C-spine more than any other technique.  Direct laryngoscopy remains the fastest and most reliable method of tracheal intubation, but this is known to cause movement of the C-spine.  Axial traction for the purpose of stabilizing the C-spine during laryngoscopy has not been proved to be protective. Cricothyroidotomy may be accomplished without C-spine movement, but no studies prove this. Benumof described the ideal method of extubation for endotracheal tube exchange as “one that permits withdrawal from the airway that is controlled, gradual, step-by-step, and reversible at any time.” The advantages of the jet stylets include guidance into the laryngeal inlet in the presence of distorted anatomy as well as attachment to jet ventilation. The adequacy of minute ventilation with jet stylets has been documented over a full range of sizes of the endotracheal tube exchanger and values for lung compliance.  Direct visualization is the most significant benefit of fiberoptic bronchoscopy, and provides the best success with the difficult airway. Many models allow application of topical anesthesia, suction of secretions, and insufflation of oxygen during exchange. Use of the fiberscope as a jet stylet has been described but not widely studied in humans.  Watson recommended that endotracheal tube exchange with the fiberscope “should be attempted with the backup of proven alternatives….” Combining the two techniques would provide backup in case of difficulty. We found three major advantages to using the fiberscope in conjunction with a jet stylet. First, it allows for examination of the laryngeal inlet for edema, which may predict further difficulties with instrumentation. Second, it is important to locate the tip of the endotracheal tube exchanger to be inside the original endotracheal tube to minimize the chances of developing barotrauma to the trachea from the jet ventilation source. Most important, however, is the security afforded by two instruments in the trachea for endotracheal tube placement guidance, because this allows for greater airway control.
Tony M. Wright, M.D., Resident in Anesthesia.
Kannupillai Vinayakom, M.B., B.S., F.F.A.R.C.S., Associate Professor, Georgetown University Hospital, Department of Anesthesia, 3800 Reservoir Road NW, Washington, DC 20007.
(Accepted for publication February 23, 1995.)