Airway management in patient with retropharyngeal cerebrospinal fluid collection with pre-existing multiple airway problems.

Sir,

Retropharyngeal cerebrospinal fluid (CSF) collection is one of the rarest complications of cervical spine surgery.[1] Here, we have highlighted the airway management in such patient with pre-existing multiple airway problems and discussed the role of different airway management techniques.

A 31-year-old patient presented with change in voice and dysphagia for 15 days. Two months ago, he had a fracture of cervical spine (C2) for which posterior fixation (occiput/C1/C2) was performed. In view of early weaning, patient was tracheostomized and decannulated after 1-month. During this time, patient was diagnosed as a case of retropharyngeal CSF collection and scheduled for redo spine surgery for CSF leak repair [Figure 1]. On airway examination, mouth opening was restricted (Mallampati III) with limited neck extension (due to previous posterior fixation) and there was a previous tracheostomy scar. Computed tomography scan revealed sub-glottis stenosis too. In view of difficult airway, awake intubation was planned. Glycopyrrolate 0.2 mg intravenously was given 20 min before the scheduled surgery. Patient was shifted to Operating Room (OR) and routine monitors were attached. Oxygen (4 L/min) was administered via nasal prong. Intravenous remifentanyl infusion (0.05 mcg/kg/min) was started and 0.5 mg midazolam was given. As the patient had altered phonation, superior laryngeal nerve block could not be performed. However, transtracheal infiltration of 2 ml of 2% lidocaine (60 mg) was performed. Considering high risk of aspiration, only lidocaine jelly was put on the posterior surface of the tongue with a spatula; however, patient developed sudden spasm. At this time, patient started obstructed breathing; however, oxygen saturation was maintained with assisted bag mask ventilation with 100% oxygen. We decided to use flexible fiberoptic intubation with 6.0 mm flexometallic endo-tracheal tube (ETT). We could pass pediatric fiberoptic bronchoscope through vocal cords but were unable to pass ETT. After three attempts of successful fiber-optic broncoscopy yet failed threading of ETT, we decided to use glidescope with fiber-optic broncoscope. We could see grade III views but could not pass the fiber-optic broncoscope as the patient was repeatedly exerting. At this time, small bolus of propofol (20 mg) was given. On the next step, bougie was used with glidescope assisted intubation but due to a fixed neck, we could not thread the bougie too. The remaining option, C-MAC videoscope (D-blade) with a bougie was tried. Grade II views could be visualized and bougie was easily passed through the vocal cords; however, J-shaped tip of bougie became stuck just after crossing the vocal cord (area of subglotic stenosis). Maintaining bougie on the same location, we decided to thread ETT No. 6 and finally, we could successfully intubate the patient with little force and slight torsion of a tube at the level of obstruction. Throughout the procedure, we could maintain oxygen saturation (>92%) with assisted ventilation. Rest of the surgery was uneventful. At the end of procedure, trachea was not extubated (in view of difficult airway) and patient was shifted to the intensive care unit for ventilation and further management.

Figure 1

Retropharyngeal cerebrospinal fluid collection and tracheal narrowing

The already fixed cervical spine limits the neck extension and produce visualization of the larynx more difficult. Moreover, if this is associated with restricted mouth opening, retropharyngeal collection of CSF and subglotic stenosis, this imposes even the most challenging airway problem for anesthesiologist. All findings were present in our patient. In addition, our patient also had altered phonation (laryngeal nerve involvement) and dysphagia (high risk for aspiration) thus making airway topicalization rather contraindicated and made this case even more challenging. Though considered as the gold standard, we could not achieve successful intubation with flexible fiber-optic scope. The C-MAC video laryngoscope is found to be useful in many difficult airway situations and equally effective as compared to flexible fiber-optic intubation.[23] A recent study also revealed that there were higher chances of successful intubation on first attempt with the C-MAC in many difficult intubation conditions.[4] In other studies, use of the glide scope resulted in longer time to successful intubation as compared to C-MAC blades.[5] In our patient also, C-MAC video laryngoscope could show us a better view of laryngeal inlet and even bougie could easily be negotiated through the vocal cords.

In conclusion, patients with fixed cervical spine with pre-existing multiple airway problems and in which proper topicalization of airway cannot be achieved; C-MAC video laryngoscope can be the considered as intubation technique of choice.