Title: Use of Handheld Point-of-Care Ultrasound in Emergency Airway Management. Chest. 2020 Sep 21;S0012-3692(20)34501-3. doi: 10.1016/j.chest.2020.09.083. 

1. What is already known about this topic?
   1. Studies on traditional clinical examination techniques, such as modified Mallampati score, thyromental distance, neck range of motion, and mouth opening, have shown the limited predictive performance of for predicting difficult airways.
   2. Confirmation of endotracheal tube (ETT) placement can be challenging and current bedside methods of confirmation are 100% reliable. 
2. What is the PICO question?
   1. This was a review article on the use of POCUS in emergency airway management, including airway (Pre-intubation) and post-intubation assessments. 
   2. Airway assessments included screening for difficult airway with cricothyrotomy preparation, and assessing aspiration risk. 
   3. Post-intubation assessments included ETT placement confirmation and lung sliding.
3. What are the main findings?
   1. Airway assessment can be done by predicting difficult laryngoscopy by identifying the distance from skin to epiglottis.
   2. If a difficult laryngoscopy is predicted then the structures can be identified for potential cricothyrotomy. 
   3. Aspiration risk can also be assessed by estimating the gastric volume, although it is generally regarded as an insignificant factor in the emergency department.  
   4. There were several described techniques to confirm ETT placement including a dynamic (real-time) assessment and static (post) assessment. 
   5. The authors of this article suggest an adequate approach is successful tracheal intubation is confirmed by a single air-filled structure with acoustic shadowing (“single bullet sign”), versus failed esophageal intubation produces two air-filled structures (“double tract sign”).
   6. The use of ultrasound in verifying bilateral lung sliding can help exclude mainstem intubation, mucous plugging, pneumothorax, blebs, or pleurodesis.
   7. “Lung pulse” sign should be excluded by pleural motion even in the absence of respiration. 
4. What are its limitations?
   1. “Handheld” is misleading. These studies typically use cart/monitor based ultrasounds which may be too cumbersome and not always readily available in emergency airway management (EAM).  
   2. There is emergency medicine literature on the use of POCUS for airway but most studies included here were not EM literature. Additionally, the authors EAM team is multi-specialty, which is the type they propose would best be able to integrate these techniques, would not be available in most emergency departments. 
   3. The current literature is primarily exploratory in design and performed electively. 
   4. This is a good summary on the current evidence available and can provide a nidus for further EM based research, larger randomized and validation studies
5. How will this article change practice?
   1. This should not definitely change our practice. It’s a good amount of positive evidence. Alternatively, these may be techniques we can begin to practice during our training and consider incorporating in the future with proper integration.

Written by: Taylor Brittan MD