Endotracheal intubation (ETI) is often employed during major surgical procedures and for respiratory support in patients who are critically ill. Not all patients can be intubated easily, however, and failure of advanced recognition of difficult intubation can result in a catastrophic scenario.

The purpose of this illustration is to demonstrate several anatomic features and bedside tests that can be used to assess difficult intubation prior to general anesthesia or in emergency situations. This set of illustrations is unique in that it combines the most common strategies for airway assessment within a single easy-to-understand composition.