**3. Assessment of difficult airway**

#### **3.1 Clinical history**

It is important to start by reviewing the previous medical records regarding airway management and whether there was any difficulty faced and how it was handled. It can be very informational to communicate with the previous anesthesia team regarding the airway management, if their anesthesia chart reflected any difficulty. Proper documentation of the airway management is important, including techniques that were and were not successful. All of this is of value if there is no worsening or newonset airway pathologies. This information should be recorded in all cases irrespective of difficult airway for the benefit of future colleagues.

In your preoperative examination, there are many medical conditions that have been associated with an increased risk of difficult intubation and airway management. In progressive disorders such as chronic rheumatoid arthritis, chronic ankylosing spondylitis, and chronic diabetes mellitus, disease involvement of the airway or neck joints should be ruled out. Rare syndromes such as Pierre-Robin syndrome, Klippel-Feil syndrome, and Treacher Collins syndrome are often associated with difficult airways. History of recent acute respiratory tract infections has increased incidence of laryngospasm and bronchospasm especially in children.

A STOPBANG questionnaire should answered by all patients prior to anesthesia, to assess the potential risk for obstructive sleep apnea (OSA). Patients with diagnosed OSA are at increased risk for difficult airway management.

Any new-onset airway pathology or worsening pathology must be documented as it will require entirely different approach to manage.

Patients presenting with a retrosternal goiter should be evaluated for signs and symptoms suggestive of tracheal compression or recurrent laryngeal nerve compression such as the degree of hoarseness or voice change and its progression and stridor. Also underlying esophageal compression resulting in drooling of secretions, dysphagia, and ability to lie supine should be documented. It should also be documented in what position symptoms are relieved.

The trauma patient with any airway injury requires a thorough evaluation. Assessment should focus on the swelling and its onset, associated pain and trismus, and time since injury. In case of chemical and thermal burns, careful assessment

should be done as mucosal edema can develop rapidly and progress very fast. Difficult airway is 10 times more commonly encountered in intensive care unit and emergency area [6].
