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Direct laryngoscopy and endotracheal intubation in adults

Steven Orebaugh, MD
James V Snyder, MD
Section Editors
Allan B Wolfson, MD
Carin A Hagberg, MD
Deputy Editors
Jonathan Grayzel, MD, FAAEM
Marianna Crowley, MD


Direct laryngoscopy (DL) and endotracheal intubation (ETI) are essential skills for a range of health care practitioners, including anesthesiologists, emergency physicians, and other clinicians expected to serve as first responders in emergency cases requiring advanced airway management. This topic will discuss the indications, contraindications, preparation, equipment, and techniques needed to perform DL and ETI in adults. The use of more sophisticated airway equipment (eg, video laryngoscopes), approaches to airway management in specific clinical circumstances, pediatric laryngoscopy, and rapid sequence intubation are all reviewed separately. (See "Devices for difficult emergency airway management outside the operating room in adults" and "The decision to intubate" and "Emergency endotracheal intubation in children" and "Advanced emergency airway management in adults" and "Approach to the difficult airway in adults outside the operating room" and "Rapid sequence intubation for adults outside the operating room" and "Neuromuscular blocking agents (NMBAs) for rapid sequence intubation in adults outside of the operating room" and "Induction agents for rapid sequence intubation in adults outside the operating room".)


In emergency medicine, the most common indications for tracheal intubation are acute respiratory failure, inadequate oxygenation or ventilation, and airway protection in a patient with depressed mental status. In the perioperative setting, endotracheal tubes may be placed in many clinical circumstances, including patients receiving general anesthesia, surgery involving or adjacent to the airway, unconscious patients requiring airway protection, or surgery involving unusual positioning [1]. Less frequently, intubation is performed for short-term hyperventilation to manage increased intracranial pressure or to manage copious secretions or bleeding from the airway [2]. (See "The decision to intubate".)


There are few absolute contraindications to tracheal intubation. Most involve supraglottic or glottic pathology that precludes placement of an endotracheal tube (ETT) through the glottis or which may be exacerbated by insertion of the ETT or laryngoscope. As an example, blunt trauma to the larynx may cause a laryngeal fracture or disruption of the laryngotracheal junction. In such cases, traction from the laryngoscope blade or pressure from a stylet within an ETT could create a false lumen or complete a partial tear of the trachea [3].

Penetrating trauma of the upper airway may also result in conditions exacerbated by laryngoscopy or ETT placement, such as a hematoma or partial transection of the airway [4]. When examination findings suggest such conditions exist, it may be safer to support oxygenation and ventilation using noninvasive means until a definitive airway can be established or to perform an immediate surgical airway, if necessary. (See "Approach to the failed airway in adults outside the operating room" and "Emergency cricothyrotomy (cricothyroidotomy)".)

Other conditions associated with difficult intubation include severe laryngeal or supralaryngeal edema as a consequence of bacterial infection, burns, or anaphylaxis [5]. In these cases, visualization of the laryngeal inlet during laryngoscopy may be impossible, and local trauma caused by the laryngoscope blade or attempts at ETT insertion can lead to increased swelling, rendering mask ventilation difficult or impossible. (See "Epiglottitis (supraglottitis): Clinical features and diagnosis", section on 'Adults'.)

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Literature review current through: Dec 2017. | This topic last updated: Dec 01, 2017.
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