Awake Retrograde Intubation: Our Experience and a Comparison between CVC Guide Wire and Zebra Guide Wire for Railroading

Background: Limited mouth opening almost always poses many difficulties not only for laryngoscopy but also for tracheal intubation. Many patients coming for oral and maxillofacial reconstructive surgeries with limited mouth opening due to pain, scars, burns or contractures involving head and neck, distorted anatomy of head, neck and oral cavity or due to previous surgeries on the oral cavity have challenging airway. In such cases the gold standard fiber optic intubation is the choice. But other alternative techniques like blind nasal intubation or awake retrograde intubation can be a very good choices at times when fiber optic bronchoscope is not available. We chose awake retrograde intubation to secure airway in our patients. We tested two different guide wires, CVC and Zebra guide wires for railroading ET tube through nasal route in these patients having limited mouth opening of less than 2cms to evaluate the ease of intubation by comparing different parameters recorded during or after intubation. Material and methods: Intubation was performed with little modifications using two different guide wires in similar scenarios. A 0.035"F central venous catheter guide wire and a 0.032"F Zebra urological guide wire were used to guide endotracheal tube nasotrachealy. 40 patients requiring oral and maxillofacial reconstructive surgeries of various types with limited mouth opening of less than 2cms with anticipated difficult laryngoscopy and intubation were chosen. Indications for the procedure included oral submucosal fibrosis, various fractures of mandible, malignancies of gingivobuccal sulcus involving retromolar trigone, temporomandibular joint ankylosis, reconstructive surgeries of face post hemimandiblectomy, internal derangement of temporomandibular joint, submandibular abscess etc. Results: Mean time taken for successful nasotracheal intubation with Zebra guide wire Mean ± SD of 3.48 ± 0.62 minutes was significantly lesser than with CVC guide wire Mean ± SD of 6.58 ± 1.21 minutes with p <0.001. Number of attempts and patient comfort were also significantly better with Zebra guide wire, p = 0.031 and p < 0.001 compared to CVC guide wire respectively. Conclusion: 0.032"F Zebra guide wire is a better, safer, inexpensive alternative to 0.035"F CVC guide for introducing or rail roading endotracheal tube through nasotracheal route during awake retrograde intubation. Our technique of awake retrograde intubation is an effective, inexpensive, safer alternative compared to other modified techniques of awake retrograde intubation without any major complications.