Video Laryngoscopy: Case Files

In just under a decade, the video laryngoscope has become a go-to device for difficult airways. Its built-in camera lets specialists explore beyond obstacles in the airway unlike traditional laryngoscopes that require direct line of sight. And the recorded footage allows clinical instructors to share interesting or unusual cases that are of enormous teaching value.

Below, you’ll find five videos from the extensive case files of D. John Doyle, MD, PhD, professor of anesthesiology at Cleveland Clinic Lerner College of Medicine of Case Western Reserve University and staff anesthesiologist in the department of general anesthesiology at Cleveland Clinic in Ohio. They show normal and challenging cases. The videos contain no audio, so Dr. Doyle has provided a written description of each case above the video.

Dr. Doyle provides a tip sheet of his most valuable advice for first-time users of the GlideScope Video Laryngoscope on page 2. Additional resources to learn about the device’s expanding utility in adult, pediatric, and infant patients can be found on page 3.

Case 445 Video Laryngoscope Intubation

##MM_VIDEO_ARTICLE_092811_RS_1##

Case 464 Video Laryngoscope Intubation

##MM_VIDEO_ARTICLE_092811_RS_2##

Case 442: Video Laryngoscope-Assisted Fiberoptic Intubation (Patient Asleep)
The clip below illustrates a new technique for teaching fiberoptic intubation (FOI) using the GlideScope video laryngoscope. Following anesthetic induction, the video laryngoscope is introduced in the usual manner, followed by introduction of the fiberoptic bronchoscope (FOB). While the resident manipulates the FOB into position, the supervisor monitors the video laryngoscope display to see where the tip of the FOB is located. The resident only looks through the FOB, not at the video laryngoscope display, as the supervisor provides verbal feedback as to the location of the FOB tip.

Once the FOB has entered deep into the trachea, the endotracheal tube is passed over the FOB into the glottis. Here, use of the video laryngoscope is again helpful, because if the endotracheal tube gets caught on the arytenoids or other laryngeal structures, it can be seen on the video laryngoscope display and appropriate corrective action can be taken, such as twisting the endotracheal tube. This technique also is useful in situations where FOI is difficult even for experienced operators, for instance, in the case of airways soiled by blood.

##MM_VIDEO_ARTICLE_092811_RS_3##

Case 479: Vocal Cord Polyps
This 40 year old woman had a large vocal cord polyp. After the induction of general anesthesia she turned out to be fairly hard to ventilate, presumably because of airway obstruction. We had a good view of the glottis but despite using a small endotracheal tube (size 5.0 MLT), the tube did not pass easily.

##MM_VIDEO_ARTICLE_092811_RS_4##

Case 610: Severe Subglottic Stenosis (Video Laryngoscope Failure)
This patient with severe subglottic stenosis was unable to be intubated using the video laryngoscope. A size 6.0 endotracheal tube was intially tried, then a 4.0 MLT. What saved the day was a DEDO laryngoscope used by the ENT service, which provided a “straight shot” with the 4.0 MLT tube. There was no problem with desaturation, thanks to generous preoxygenation. In retrospect, I probably should have used a bougie or Frova intubation catheter.

##MM_VIDEO_ARTICLE_092811_RS_5##

 

16 Tips for GlideScope Video Laryngoscopy

1. Use the device for most easy / routine cases until you are very comfortable with its use. That way, when you need it for a particularly difficult airway case you will already be quite familiar with the mechanics of the device. (In one study, primary intubation with the device was successful in 98 percent of 1,755 cases and rescued failed direct laryngoscopy in 94 percent of 239 cases.)

2. When placing the GlideScope, I like to insert it slightly to the left of the midline to ensure adequate room to the right of the device to get the tube into the mouth. This is particularly important when large diameter tubes are inserted, such as the double lumen tubes used for thoracic surgery or the wide-diameter tubes with embedded electrodes used in many thyroid surgery cases.

3. When placing the endotracheal tube, start by placing it gently under direct vision and then switch to the monitor view once it is has been gently placed deep into the oropharynx. This two-phase approach is recommended to reduce the chance of causing harm or injury to one of the tonsillar pillars or to the soft palate.

4. The angulation of the tip of the endotracheal tube is very important. I personally use a bend of about 90 degrees using a disposable malleable stylet, but many experienced users recommend using 60 degrees. In one study a 90 degree bend turned out to be a little bit better than a 60 degree bend. Too little a bend, and the endotracheal tube tip points to the esophagus and not the glottic aperture; too much of a bend and the endotracheal tube tip tends to get caught on the anterior tracheal wall.

5. A reusable rigid stylet that matches the angulation of the blade is also available; it has been shown to be equal in efficacy to a disposable malleable stylet. Make sure that it is not thrown out by accident.

6. Endotracheal tubes with nice soft tips are available to make passage of the endotracheal tube just a little less traumatic.

7. It is not uncommon that videolaryngoscopy users achieve an excellent view of the glottis but experience difficulty advancing the endotracheal tube into the glottic aperture because of the tube abutting against the anterior tracheal wall. If this happens, withdrawing the stylet by 3 to 5 cm tends to straighten the tip of the tube and propel it in the right direction. Other techniques, such as the “gear stick” technique, the “reverse loading” technique or the “J-shape” technique also can be helpful.

8. Paradoxically, maximizing the size of the glottic view with full and complete advancement of the GlideScope into the oropharynx may adversely impact on the ease of intubation. With more limited advancing of the device, the “approach angle” of the endotracheal tube is often more amenable to easy passage of the tube into the glottis. That is, the position that provides the best glottic view is generally not the position that makes intubation the easiest, where a “good enough” view is usually the most favorable. Where a suboptimal view is obtained, use of an airway introducer (Eschmann guide) can sometimes be helpful.

9. Nasal intubations are surprisingly easy. No stylet is used. Manipulate (flex or extend) the head to ensure easy passage of the tube. Forceps are rarely needed. However, use of regular Magill forceps is difficult in this setting; rather, use a pair of curved intubating forceps should the need arise.

10. Using the GlideScope for awake intubation can be valuable when fiberoptic scopes are unavailable. It is accomplished after the patient’s airway has first been well anesthetized with lidocaine or other drug.

11. GlideScope-assisted fiberoptic intubation is another option to consider for difficult airway management. It can be performed either awake or under general anesthesia depending on the clinical circumstances, and can be used to help teach fiberoptic intubation. The technique begins with introduction of the GlideScope, followed by introducing the fiberoptic bronchoscope. In the teaching setting, the instructor is able to use the video laryngoscopy device to see the tip of the bronchoscope as controlled by the student, so the instructor can provide real-time guidance to supplement the view provided by the bronchoscope. When used for purely clinical purposes, the GlideScope can assist in a fiberoptic intubation by providing an alternative view of the airway; such a view can be helpful, for example, in the case of a bloody airway or severely distorted anatomy.

12. Remember that the video laryngoscope can be useful in swapping out endotracheal tubes.

13. The video laryngoscope also can be used in neonates and pediatric patients.

14. The GlideScope is available in both a conventional format as well as in a format employing disposable blades. While they are equal in performance, the use of a disposable blade is valuable when rapid turnaround is needed.

15. There is evidence that video laryngoscopy may involve the use of less force compared to direct laryngoscopy.

16. Finally, remember that there are situations where the video laryngoscope will fail you, and that these are often unexpected. Always have a backup plan for this eventuality. For me, this usually involves asleep fiberoptic intubation, asleep fiberoptic intubation in conjunction with the GlideScope (as described above), insertion of a supraglottic airway followed by use of a bougie tube, or simply waking up the patient.

D. John Doyle, MD, PhD is professor of anesthesiology at Cleveland Clinic Lerner College of Medicine of Case Western Reserve University and staff anesthesiologist in the department of general anesthesiology at Cleveland Clinic in Ohio.