Outline the advantages and disadvantages of videolaryngoscopy as compared to direct laryngoscopy.

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College answer

Videolaryngoscopy (VL) utilizes video camera technology to visualize airway structures and facilitate endotracheal intubation. It could allow good exposure of the glottis without the need to align oral, pharyngeal and tracheal axes.

Advantages:
•    Improve laryngeal view and glottic visualization
a.    Improve laryngeal view: allow assessment of larynx, facilitate procedures, e.g. NG Tube placement, ETT exchange
b.    reduce failed intubations
•    VL requires the application of less force to the base of the tongue, therefore is less likely to induce local tissue injury.
•    Allows less cervical spine movement for intubation compared with direct laryngoscopy
•    Allows others to view the screen
a.    Allow assistant to help facilitate endotracheal intubations, e.g. enable real time cricoid force optimization, optimal external laryngeal manipulation to improve view
b.    Facilitate teaching and supervision of endotracheal intubation
•    Can allow video recording to provide an official record of tracheal intubation
•    Faster learning curve than direct laryngoscopy

Disadvantages:
•    Possible difficulty in passing endotracheal tube despite improved glottic visualization especially with hyper angulated ‘D’ blade, termed “laryngoscopy paradox”. Use of a bougie or stylet would be recommended. Hyper angulated blades may prolong easy intubations.
•    Multiple devices exist with unique learning curves. Training is required
 
•    Blood, secretions and vomitus in the airway as well as fogging can hamper use of VL
•    Potential for false sense of security and lack of preparation for difficult airway. VLs are not the panacea for difficult airway management. All airway plans that utilize VL require a plan for technical failure.
•    VL are more expensive. Additional maintenance and disinfection arrangement.
•    Potential weakening in development and maintenance of direct laryngoscopy skill set
 

Discussion

Advantages:

  • Education and communication
    • Enhances training of junior staff in anatomy
    • Skill set can be transferred to direct laryngoscopy (Low et al, 2008)
    • In reverse, direct laryngoscopy skills transfer well to videolaryngoscopy
    • Communication regarding difficulty is made easier
    • Medical information regarding intubation progress is exchanged more easily
  • Intubation success
    • Videolaryngoscopy improves the likelihood of a "successful" intubation in difficult intubation scenarios (Pieters et al, 2017) and unsorted critically ill patients (De Jong et al, 2014) as well as in general ward situations  (Baek et al, 2018).
    • Relatively unskilled staff have comparatively higher rates of success
  • Safety
    • Allows intubation in suboptimal position
    • Allows the airway assistant to improve your view in a more guided informed fashion
    • Less fore required for laryngoscopy, which should translate into less injury
  •  Convenience and cost
    • It permits a permanent video record of the intubation
    • Cost is relatively low compared to other interventions (hello, eculizumab)

Disadvantages:

  • Education and communication
    • The airway anatomy may be different to what is seen on direct laryngoscopy
    • Direct laryngoscopy skills must share training time with videolaryngoscopy skills during medical training, which degrades the former. However, direct laryngoscopy is still the dominant technique used routinely in anaesthesia
    • There are multiple devices each of which is used differently and requires different training
    • The videolaryngoscope screen can act as a distraction to the team
  • Intubation success
    • The view is not guaranteed to be good: secretions, blood or mist may cover the camera
    • Even if the view is good, the passage of the tube is not guaranteed to be easy
  • Safety
    • Because of the screen taking attention away from the oropharynx, the passage of airway equipment into the mouth and oropharynx is not directly observed. Dental and pharyngeal damage may result. Aziz et al (2008) reported a 1% rate of traumatic laryngoscopy, including vocal cord trauma, one tracheal injury, one trauma to the hypopharynx, one tonsillar perforation, and two dental injuries (21 cases from a series spanning 2 years).
  • Convenience and cost
    • Videolaryngoscopy equipment is expensive and will not be available in resource-poor environments
    • Maintenance and disinfection is time consuming, taking the device out of commission for prolonged periods
    • The availability of a video record raises privacy concerns and exposes staff to medicolegal risk

References

References

Cooper, Richard M., et al. "Early clinical experience with a new videolaryngoscope (GlideScope®) in 728 patients." Canadian Journal of Anesthesia 52.2 (2005): 191-198.

Cavus, Erol, et al. "The C-MAC videolaryngoscope: first experiences with a new device for videolaryngoscopy-guided intubation." Anesthesia & Analgesia 110.2 (2010): 473-477.

AnaesthesiaUK have a nice page about McCoy blades.

Cook, T. M., and J. P. Tuckey. "A comparison between the Macintosh and the McCoy laryngoscope blades." Anaesthesia 51.10 (1996): 977-980.

Doyle, D. J. "A brief history of clinical airway management." Revista Mexicana de Anestesiologia 32 (2009): S164-S167.

McCoy, E. P., and R. K. Mirakhur. "The levering laryngoscope." Anaesthesia48.6 (1993): 516-519.

Chemsian, R. V., S. Bhananker, and R. Ramaiah. "Videolaryngoscopy." International journal of critical illness and injury science 4.1 (2014): 35.

Norris, A., and T. Heidegger. "Limitations of videolaryngoscopy." (2016) BJA: 148-150.

Baek, Moon Seong, et al. "Video laryngoscopy versus direct laryngoscopy for first-attempt tracheal intubation in the general ward." Annals of intensive care 8.1 (2018): 83.

Pieters, B. M. A., et al. "Videolaryngoscopy vs. direct laryngoscopy use by experienced anaesthetists in patients with known difficult airways: a systematic review and meta‐analysis." Anaesthesia 72.12 (2017): 1532-1541.

De Jong, Audrey, et al. "Video laryngoscopy versus direct laryngoscopy for orotracheal intubation in the intensive care unit: a systematic review and meta-analysis." Intensive care medicine 40.5 (2014): 629-639.

Low, D., D. Healy, and N. Rasburn. "The use of the BERCI DCI® Video Laryngoscope for teaching novices direct laryngoscopy and tracheal intubation." Anaesthesia 63.2 (2008): 195-201.

Aziz, Michael F., et al. "Routine Clinical Practice Effectiveness of the Glidescope in Difficult Airway ManagementAn Analysis of 2,004 Glidescope Intubations, Complications, and Failures from Two Institutions." Anesthesiology: The Journal of the American Society of Anesthesiologists 114.1 (2011): 34-41.