Ultrasonography is an established modality in medical imaging and is evermore entering clinical practice. This chapter provides an introduction to the principles of clinical ultrasonography. It describes the use of airway ultrasonography for identification of the cricothyroid membrane, the trachea and for confirming correct tracheal intubation. Bedside ultrasonography by the anaesthetist has a much higher success rate than palpation for identifying the cricothyroid membrane, especially in patients with neck pathology. It should be applied before initiation of airway management and not be delayed until airway problems are apparent. The role of lung ultrasonography for identification of normal ventilation and pathology is described. Gastric ultrasonography for assessing the starvation status of a patient is described.

Transoral robotic surgery (TORS) allows resection of otherwise inaccessible pathology. It generates unique challenges to the airway management of the patient due to the shared location of the anaesthetist and the surgeon’s equipment. A close cooperation between the anaesthetic and surgical team is required, for the safe handling of the airway. The anaesthetist needs to be able to employ a variety of airway manoeuvres in order to ensure the airway patency throughout the perioperative and post-operative period. The airway of the TORS patient is characterised by its dynamic nature, as it changes due to the surgery, swelling and bleeding.

Bleeding in the upper airway is an important cause of airway-related death, even in young and otherwise healthy individuals. The estimated lifetime incidence of epistaxis is approximately 60%; post-tonsillectomy haemorrhage occurs in 6–15% of tonsillectomy cases; and bleeding following surgery for malignancy in the upper airway is one of the leading causes of requirement of an emergency front of neck airway. Pre-oxygenation may be difficult or impossible. Cornerstone techniques commonly employed to secure the airway, such as direct/videolaryngoscopy and flexible optical laryngoscopy, may be ineffective due to soiling of the hypopharynx – and the equipment – with blood. Supraglottic airway devices may be employed but are typically of limited efficacy due to the increased risk of aspiration and their potential interference with surgical access to the bleeding site in the hypopharynx, glottis and trachea. The clinician may thus be forced to use other, less familiar techniques and modify their approach to airway management, particularly if bleeding is profuse and/or conventional intubation and airway rescue techniques are predicted to be difficult. Cardiovascular compromise from blood loss may further complicate airway management and anaesthesia. We identify techniques and strategies that may be employed in this situation.

A major challenge of airway management is safe care of the patient with a narrowed airway. Small tracheal tubes offer one solution but pose a problem with ventilation. While inspiration may be achieved by use of a high-pressure source to overcome airway resistance, two problems exist: first, the high-pressure source demands technical excellence and exposes the patient to a high risk of barotrauma; second, conventional (passive) exhalation through a narrow tube is slow and cannot achieve a normal minute ventilation with a tracheal tube of less than 4.5 mm diameter. Recently technical developments have led to the ability to assist expiration and make it, like inspiration, an active process. This technology is used in the Ventrain manual ventilator, the 2.4 mm wide Tritube tracheal tube and the Evone automatic ventilator. These new devices and the applied technology enable solutions for safe management of the narrowed upper airway.