To the Editor:—

Fiberoptic intubation is a very useful technique for patients whose tracheas are difficult to intubate using conventional methods. However, insertion of a fiberscope and insertion of an endotracheal tube over the fiberscope into the trachea are two major difficulties.1We encountered an unusual difficulty during removal of the fiberscope after successful tracheal intubation. Our search revealed no such difficulty reported in the literature.

A 30-yr-old man with atlanto-axial dislocation came for trans-oral decompression and posterior fixation. An awake intubation was planned. After adequate oral and intravenous sedation, bilateral superior laryngeal nerve blocks, and topical anesthesia to the airway, a bite block was inserted.

Endotracheal tube (8.5, polyvinyl chloride) was loaded over the fiberscope (Fujinon F B 120-p, Fujinon Corporation, Saitoma, Japan). A long catheter (drug spray cannula) was inserted through forceps port of the fiberscope for the administration of local anesthesia in the event of inadequate anesthesia. This catheter comes with a fiberscope set.

The fiberscope and enodotracheal tube were inserted through the mouth. Excellent local anesthesia was observed while introducing the fiberscope and the tube into the trachea, which was performed within 30–40 s. The patient remained comfortable during and after intubation of the endotracheal tube without any sign of distress. Administration of local anesthesia was not required. With successful intubation, we tried to remove the fiberscope. Initially we felt some resistance. After applying slight force, the fiberscope came out but the injection catheter remained inside the tube. We were unable to remove the catheter with moderate force. To determine the reason, we reinserted the fiberscope into the trachea over the catheter. We noticed that the catheter had gone beyond the tip of the endotracheal tube, making a U shape over the edge of it. We removed the tube along with the fiberscope and the catheter. The catheter was not used during the second attempt of awake fiberoptic intubation, which was accomplished without difficulty. Subsequent endoscopic examination of the distal trachea and major bronchi revealed normal anatomy.

We hypothesized that during advancement of the endotracheal tube over the fiberscope, the injecting catheter migrated beyond the tip of the fiberscope. With further advancement, it became U shaped over the edge of the tube, and one arm of it got trapped between the tube and the trachea, which caused it to be stalked within the tube (figure 1).

Fig. 1. The drug injection catheter protruding out from the fiberscope and making a U shape over the tip of the endotracheal tube simulating the condition  in situ .

Fig. 1. The drug injection catheter protruding out from the fiberscope and making a U shape over the tip of the endotracheal tube simulating the condition  in situ .

Inadvertent advancement of the tip of the fiberscope through a side hole (Murphy eye) of an endotracheal tube, causing difficulty in intubation has been reported.2 

To eliminate this kind of problem with the use of an injection catheter, we suggest a simple measure. The catheter should be fixed with adhesive tape or a rubber band at the inlet of the forceps port so that it will not protrude from the tip of fiberscope in situ .

*Neurosciences Centre, All India Institute of Medical Sciences, New Delhi, India.


Asai T, Shingu K.. Difficulty in advancing a tracheal tube over a fibreoptic bronchoscope: incidence, causes and solutions. Br J Anaesth 2004; 92:870–81
Nichols KP, Zornow MH: A potential complication of fiberoptic intubation. Anesthesiology 1989; 70:562–3