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Overview of tracheostomy

Robert C Hyzy, MD
Section Editor
Praveen N Mathur, MB, BS
Deputy Editor
Geraldine Finlay, MD


Airway access for mechanical ventilation can be provided either by endotracheal or tracheostomy tube. During episodes of acute respiratory failure, patients are generally ventilated through an endotracheal tube. Changing to a tracheostomy tube is often considered when the need for mechanical ventilation is expected to be prolonged. An overview of clinical issues related to tracheostomy will be discussed here. General issues regarding endotracheal intubation and prolonged ventilation are presented separately. (See "Complications of the endotracheal tube following initial placement: Prevention and management in adult intensive care unit patients" and "Management of the difficult-to-wean adult patient in the intensive care unit" and "Management and prognosis of patients requiring prolonged mechanical ventilation".)


The relative advantages and disadvantages of tracheostomy and endotracheal intubation are outlined in the table (table 1).

Work of breathing — Data from small studies suggest that work of breathing, pressure-time product, airway resistance, peak inspiratory pressures, and intrinsic positive end-expiratory pressure (ie, auto-PEEP) decrease after tracheostomy in both ventilated and spontaneously breathing patients [1-4]. As a result, standard weaning parameters such as the rapid shallow breathing index improve in difficult to wean patients following the conversion from endotracheal tube to tracheostomy [5]. In addition, ventilator synchrony and triggering may be enhanced, although tidal volume, respiratory rate, and dead space ventilation remain unchanged [1,6]. These changes – along with other variables such as secretion, clearance, and patient comfort – may facilitate weaning from mechanical ventilation.

Aspiration — Aspiration of oropharyngeal contents is common with both tracheostomy and endotracheal intubation. It is a result of both pharyngeal pooling of secretions above the airway cuff and delayed triggering of the swallow response [7,8]. The risk of aspiration is directly related to the amount of oropharyngeal secretions.

Videofluoroscopic studies have failed to demonstrate an alteration in swallowing mechanics just prior to decannulation [9]. However, in patients who have a tracheostomy, aspiration occurs in 30 to 50 percent and is clinically silent in 75 to 82 percent of cases [10-12]. Occlusion of the tracheostomy with a cap or finger for phonation does not significantly increase the frequency of aspiration [12]. The likelihood of aspiration may decrease somewhat after a tracheostomy has been present for three weeks [11].


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Literature review current through: Sep 2016. | This topic last updated: Oct 13, 2016.
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