A 77-year-old man presents to the urgent outpatient ORL clinic with difficulty breathing and stridor at rest. He has a high BMI (35 kg·m–2) and a complex cardiac history. He presented to the Emergency Department a week earlier and began a course of prednisone 30 mg for airway swelling. His vital signs are temperature 37°C, heart rate 100 beats per minute, respiratory rate 22 breaths per minute, blood pressure 165/90 mmHg, and oxygen saturation (SpO2) 95% on room air. The patient is seated, using his accessory muscles respiration with severe stridor.
A computed tomographic (CT) view of the head and neck is performed, which reveals an extensive thyroid carcinoma and a 1 mm opening at the level of the glottis (Figure 45.1). Previous anesthetic records showed a Cormack-Lehane Grade 1 view using a Macintosh laryngoscope. The remainder of his history and investigations were unremarkable.
The computed tomographic view of the head and neck, showing 1-mm internal airway diameter: (A) 1-mm subglottic airway; (B) left thyroid ala; (C) C5 spinous process.
What Are the Four Fundamental Techniques of Airway Management?
The primary goal of airway management is the provision and maintenance of alveolar oxygenation. Traditionally, there have been four fundamental techniques described that have the ability to provide oxygen under anesthesia. These include face-mask ventilation (FMV), ventilation via an extraglottic device (EGD), an endotracheal tube (ETT), or through front-of-neck access (FONA). FMV involves an airway practitioner holding an appropriately sized face mask over a patient’s mouth and nose achieving a seal in which no gas can escape. Oxygen is delivered either via spontaneous ventilation from the patient, or through a ventilatory system (positive pressure generated by a pressurized bag or mechanical ventilator) (see Chapter 8). An EGD is any device that is inserted into the pharynx providing a conduit of gas flow from a ventilatory system to the patient (see Chapter 13). An ETT is defined as any tube that is inserted into the trachea to provide a seal for ventilation directly into the lungs; this is usually inserted under visual guidance, either directly via line-of-sight (see Chapter 9), or indirectly using a video camera-based technique (see Chapters 10 and 11). Finally, FONA is the use of any technique to gain access to the trachea for oxygen delivery. This can include a scalpel technique (scalpel-bougie-tube or open surgical technique) or a cannula-guided technique (see Chapter 14).
Utilizing these four fundamental methods of oxygenation, various organizations have developed and revised guidelines and strategic plans to assist practitioners in making critical decisions when providing oxygenation under challenging situations.1–4 While these guidelines and strategic plans help in managing patients with a ...