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Use of Polarized Sunglasses During Video Laryngoscopy: A Cause of Difficult Prehospital Intubation

  • Adam James Smith (a1), Ken Jackimczyk (a1) (a2) (a3), Bruce Horwood (a1) (a2) (a3) and Daniel Christenson (a4)



In the prehospital setting, many providers advocate for video laryngoscopy as the initial method of intubation to improve the likelihood of a successful first attempt. However, bright ambient light can worsen visualization of the video laryngoscope liquid crystal display (LCD).

Case Report

A patient involved in a motor vehicle accident was evaluated by an Emergency Medical Services (EMS) crew. Initial endotracheal intubation attempt using video laryngoscopy was aborted after the patient desaturated. The primary reason for the failure was poor visualization of the video laryngoscope LCD, despite attempts to block direct sunlight. Debriefing revealed that the intubating provider was wearing polarized sunglasses.


Because LCDs emit polarized light, use of polarized sunglasses may cause the display to appear dark. Thus, the purpose of this Case Report is to raise awareness of a potential safety issue that is likely under-recognized by prehospital providers but can be easily avoided.

SmithAJ, JackimczykK, HorwoodB, ChristensonD. Use of Polarized Sunglasses During Video Laryngoscopy: A Cause of Difficult Prehospital IntubationPrehosp Disaster Med. 2019;34(1):104–107.


Corresponding author

Correspondence: Adam James Smith, MD 2252 N 44th St #2099 Phoenix, Arizona 85008 USA E-mail:


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Conflicts of interest: none



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