Category Archives: Rigid scopes

Split-screen dual endoscopy

Some new devices/monitors such as the Glidescope Core or Storz CMAC 8404 now allow viewing two video feeds on one display, either as a “picture-in-picture” or side-by-side display. Here is a demo of split-screen dual endoscopy with Macintosh-blade VL and optical stylet:

Dual endoscopy using split screen. It would have been good to have warmed the optical stylet (right) to prevent fogging of the lens. Orienting the VL on the left and stylet on the right improves coordination between left and right hands holding the devices.

For more discussion on dual endoscopy, see the original post from 2018 here on OpenAirway which is being updated over time.

Dual endoscopy demo

Here’s a brief clinical example of dual endoscopy using the CMAC VL and VS (video stylet).  This case was performed for teaching purposes, rather than a difficult airway.  Note the endoscopic view appearing as a picture-in-picture is from the editing; the images are on two separate displays.  (It starts a little late due to the author forgetting to press the record button on the device).

 

Dual endoscopy

“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”:

  1. 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
  2. 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.
  3. 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.

Here’s a brief clinical example of dual endoscopy using the CMAC VL and VS (video stylet).  This case was performed for teaching purposes, rather than a difficult airway.  Note the endoscopic view appearing as a picture-in-picture is from the editing; the images are on two separate displays.  (It starts a little late due to the author forgetting to press the record button on the device).

 

Some of the newest devices (eg. CMAC 8404; Glidescope Core monitors) allow both images to be displayed on the screen simultaneously, either as a “picture in picture” view, or side by side. If using the latter, orientating the images so that the VL is on the left and endoscope on the right is convenient, as this matches the two hands being used. Here’s an example, again in a patient with an easy airway, but simulating CL3 view:

Dual endoscopy using CMAC3 and Bonfils. It would have been good to have warmed the Bonfils before starting, to prevent the fogging of the distal lens.

Rigid Intubation Scopes

Rigid endoscopes are very valuable tools for intubation in certain difficult scenarios, but are not commonly used in most centres.  The techniques and learning curve differ significantly from normal direct laryngoscopy, requiring independent practice to become proficient.  Pictured here are (left to right) a rigid bronchoscope, Bonfils, Levitan and Shikani optical stylets (rigid intubating endoscopes).

(L to R) Rigid bronchoscope, Bonfils, Levitan and Shikani optical stylets.  Click to enlarge.
(L to R) Rigid bronchoscope, Bonfils, Levitan and Shikani optical stylets. Click to enlarge.

This is the set-up for basic training on an UCT Anaesthesia Airways course.  Which of these devices have you used?  Do you have tricks or comments to share?