In this edition of Tech Doc we continue our series on difficult airway devices. Last month we covered light wands and as you may recall, two of their biggest drawbacks are the steep learning curve and the rapid erosion of skills if not used regularly. This month we will cover the Storz Berci-Kaplan DCI Video Laryngoscope, a device with antithetical attributes to the light wands. The strength of this laryngoscope lies in the fact that it can be used like any Macintosh laryngoscope blade – so there’s no learning curve – and as most EPs’ go-to device there is no degradation of skills as long as you get the opportunity to intubate.
The Storz Berci-Kaplan DCI Video Laryngoscope requires several components with a large up-front investment so let’s cover the hardware first. The foundation of the video laryngoscope is the samae as the foundation for the entire Storz video line. It starts with the light source and video camera box each with its own set of cables running to the laryngoscope blade itself. The light source intensity is fully adjustable with a long-life bulb and a choice of multiple cable lengths in the run to the handle. The video source also has video cables that run to a flat-panel display which is mounted on a cart. The video feed can also be passed into a video recording device (I simply use a handheld camcorder) to record and archive intubations for future teaching or review. The cart serves as the home for your new investment but can double as a space for other intubating devices as it has multiple drawers. The large up-front cost can be offset if you already have or plan to buy a Storz video cart for other devices as then you only need to purchase the laryngoscope and light cable. Another option soon to be released is the C-Mac which is a similar portable system with built-in screen for under $20,000 (but that is for another review).
The heart of the video laryngoscope lies in the camera head which fits into the laryngoscope handle similar to the way a magazine fits into a pistol grip. The camera head sends the light-source to the laryngoscope as well as returns the image to the video system. The camera head is also where you control the multiple aspects of image control including white-balance, contrast, tint, focus, etc.
In this myriad of cables lies one of the video laryngoscopes few weaknesses...clutter. The video laryngoscope requires a light cable with its own specific adaptor meaning that if you have other Storz fiber-optic devices you’ll need yet another pricey light cable for your new laryngoscope. You’ll then have the video cable run as well as cable plugging the entire cart into the wall as this device must be plugged in to function. What this means to users is lots of cables to keep clean and free from wheels and drawer pinches; one crimp in the fiber-optics and your very expensive cart will likely be useless.
Once the cables are plugged-in and the settings calibrated the device itself if pretty straight forward to use; place the blade in the oropharynx as you would any other Macintosh. There are a couple of caveats, however. The handle for the Storz video laryngoscope is slightly longer and bulkier than standard handles as it has to accommodate the camera system. Along with that is the fact that the light and video cables come out from the back of the handle. Both of these properties can impede placing the blade in the mouth in patients with large chests, short necks, or who have C-spine precautions as the handle cannot clear the chest. You can adjust for this by canting the blade slightly clock-wise until the blade is deep enough in the oropharynx to allow the handle to clear the chest. This is usually possible once inserted just a couple of centimeters into the mouth.
A shortcoming of all fiber-optics is that blood or secretions can quickly obscure your view. The Storz laryngoscope largely overcomes this by placing the lens about 1/3 of the way back from the tip of the blade. This keeps it clear from most debris but obscuration of your view can still be a problem with patients who have a lot of blood or secretions. You can adapt for this by not “snow-plowing” secretions or blood onto the tip of the blade allowing it to pile up on the lens. The next obstacle to good fiber-optics becomes apparent if your patient isn’t paralyzed: respirations will often fog your lens. You can prepare for this by placing a thin layer of surgi-lube or the patient’s own saliva on the lens.
Now that the prep and hassle are out of the way the fun begins. The first thing you’ll likely notice is just how damned bright the light is. The second thing you’ll notice is that the picture leaves a bit to be desired. While it is certainly clear enough to see what you want to see it is a bit on the hazy side. Storz has improved on this with a new high-definition head which I have not used as of this writing. You can use the video laryngoscope as a standard mac blade or preferably as an indirect intubating system. When doing standard laryngoscopy you have to align the oral, pharyngeal, and laryngeal axes in order to visualize the cords. Indirect intubation allows you the benefit of only having to align the pharyngeal and laryngeal axes which lie along much more similar angles when compared to the oral axis. By eliminating the oral axis you make anterior airways much easier to intubate. The downside to indirect intubation is the need to control movements based on a 2-D screen view as compared to the 3-D view you are used to along with the dissociation of what you see and what you are doing. This hand-eye coordination is easily acquired by those who play video-games but non-game players often have a steeper learning curve. So for those who could never convince the significant other to get that Xbox 360 use this article as ammo. When intubating indirectly the technique is the same as you have always used without as much manipulation of the laryngoscope.
While the video laryngoscope is great for the above uses my favorite application of this device is as a teaching tool. I work in a large academic emergency department where residents do most of the intubations. Thanks to the Storz video laryngoscope, gone are the days of asking, “What do you see? What do you see? What do you see!?!” I have the residents use the laryngoscope like a standard mac blade while I have the screen turned towards me so I can see the view from the laryngoscope which is usually better than the resident’s view. This view is great for determining blade depth (I’m amazed at how many people either place the tip of the mac way too deep or too shallow) as well as watching the ETT go into the right hole. Having a real-time view of the oropharynx allows for teaching opportunities that would otherwise be impossible. The Storz Berci-Kaplan DCI Video Laryngoscope operates as a great standard intubating laryngoscope as well as a difficult airway device with little to no learning curve. But where this setup really shines is as a teaching device. Short of head-mounted cameras I cannot think of a better method for real-time teaching of intubation skills. A Macintosh-style video laryngoscope is a versatile addition to anyone’s airway arsenal.
STORZ- The Basics
-Little to no learning curve
-Variety of uses
-Great teaching device
-Ability to record intubations
-Expensive up-front cost*
-Lots of clutter
-Video Tower: $32,000
19-inch radiance monitor
SD camera box
SD camera head
-HD Video Tower: $40,000
23 Inch HD Monitor
HD Camera Box
HD Camera Head
-Video Mac/Miller/Dorges Blades: $3,000 each
SD and HD Towers include extension arm, storage for flexible scopes, 300 watt Xenon light source and a light cable.