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Optimal lighting is important during airway procedures. Increased ambient lighting allows for better equipment preparation and procedure execution. However, EMS clinicians often need to perform airway interventions in suboptimal lighting conditions, such as at night, while conducting military operations, in a confined space rescue, or in indoor areas with poor lighting. A common pitfall of intubation is equipment failure resulting in suboptimal airway illumination; for example, broken laryngoscope bulbs, dead laryngoscope batteries, or damaged airway equipment. Regular equipment checks and use of protective carrying cases are essential aspects of practice. Spare bulbs and batteries should always be part of the standard airway kit. Simple procedures, such as rotating batteries on a regular basis, might have a big effect on airway illumination.

Studies have identified that there is variation in light output among different laryngoscopes. When the light output of curved laryngoscope handles at 19 emergency departments in the Philadelphia area was evaluated, the median luminance varied widely from 11 lux to 5,627 lux (lux is the SI unit of illuminance equal to 1 lumen per square meter) [8]. Factors that may influence illumination brightness include bulbs/laryngoscope type (fiber optic versus regular), condition of batteries, and equipment condition (e.g., multiple sterilizations potentially causing damage to light output).

The influence of laryngoscope illumination grade on time to successful mannequin intubation has been assessed [9]. Intubations were conducted on mannequins with three clinically plausible intensities of light: high (600 lux), medium (200 lux), and low (50 lux). At perceived suboptimal intubation lighting conditions (50 lux), there was no difference in time to intubation on mannequins in this study. Clinicians can see the larynx at very low light levels [10]. The minimal acceptable lighting, depending on bulb type, is anywhere from 9 to 34 lux. The notion is straightforward. Low‐complexity intubations may be possible at very low light conditions, as the airway operator is familiar with anatomy and other visual clues that will lead to a successful intubation. Difficult airways may require increased lighting to identify anatomical landmarks.

If conditions are such that achieving sufficient lighting to facilitate laryngoscopy is not possible, then at least three options exist. Digital intubation may be accomplished using solely tactile feedback. If available, intubation may be achieved using a lighted stylet. Finally, supraglottic airway insertion requires no illumination of the airway (see Chapter 3).

Suboptimal suction manifests as similar visualization challenges. While electric portable suction equipment may be effective, it is subject to breakdown and malfunction for myriad reasons. Manual suction devices may suffice in some situations but not others. In all cases, EMS clinicians should be prepared for circumstances when visualization is suboptimal and have knowledge, abilities, and equipment ready. As with suboptimal illumination, depending on the specific clinical situation, EMS clinicians may employ a gum elastic bougie for tactile feedback and orientation, lighted stylet, or blindly inserted supraglottic airway, or proceed to digital intubation.