The Bonfils is a rigid fibreoptic intubating endoscope, which can be used to provide fibreoptic assisted laryngoscopy, or as a single device for intubation. Both the midline and retromolar approach can be used. It is well suited to patients with high-grade laryngoscopy (Cormack-Lehane grades 3 and 4), patients with limited mouth opening, or floor of mouth masses. It cannot be used for nasal intubation, but can be used through some specific supraglottic airways.
Karl Storz have a useful ‘Silver Book’ on the clinical use of the Bonfils, which is fully referenced. You can request a physical copy from them or download the PDF here:
McGuire & Younger published a CEACCP article in 2010 which addresses various forms of indirect laryngoscopy, including some (not all, alas) of the rigid intubating endoscopes. It is open access on the BJA Education site.
Thong & Wong published a thorough review in A&A on the device in 2012. You can access it free here on the journal site (Open Access!)
Basic overview and fibreoptic-assisted laryngoscopy:
3.5mm Bonfils intubation in a child with a severe sub mental abscess (read more about the case here):
“Dual endoscopy” refers to using two devices – usually a video laryngoscope and a rigid or flexible endoscope – to manage an airway. The Bonfils (or Shikani or Levitan) optical stylet is often used in this context. Performing dual endoscopy provides “three levels of protection”:
- If the glottic opening is easily seen with the laryngoscope, the rigid endoscope simply acts as an ideally shaped or steerable stylet to introduce the tube
- If the view is poor (CL grade 3 or 4), the laryngoscope can be used to guide the tip of the ETT and endoscope “into the ballpark”, and then the final positioning of the tip of the tube through the vocal cords is achieved with the endoscope.
- If the airway is badly soiled or swollen (eg. ongoing bleeding or angioedema), the endoscope can be used as a lightwand for a transillumination technique. (Remember lightwands, anyone?)
Here’s a brief informal video explaining the first two points, using the CMAC VL/VS:
Another dual endoscopy approach is “VAFI” (video-assisted flexible/fibreoptic intubation), where a VL is used to help place a flexible endoscope, whereafter the rest of the intubation is continued using the flexible. Several good case reports of this technique are described in the literature.