In critically ill patients, tracheostomy is most commonly performed to facilitate delivery of prolonged mechanical ventilation. Less frequently, it may be performed for relief of upper airway obstruction or for management of chronic pulmonary secretions.
The most compelling reason to perform tracheostomy for patients requiring prolonged mechanical ventilation is to improve patient comfort and decrease sedation requirements.
The available evidence base suggests that performing tracheostomy early in patients expected to require prolonged mechanical ventilation does not reduce mortality, rates of ventilator-associated pneumonia, or duration of intensive care unit admission.
Surgical tracheostomy and percutaneous dilational tracheostomy (PDT) have comparable complication rates, but PDT is often more convenient and requires less resources to perform.
Cricothyroidotomy, rather than tracheostomy, should be the surgical airway of choice in emergency situations, except in the unusual case of subglottic obstruction.
In cases of accidental tracheostomy tube dislodgement occurring before a mature tract has formed, blind attempts at reinserting the tracheostomy tube risk creating a false passage anterior to the trachea. Endotracheal intubation from above is the safest method of airway control in the early posttracheostomy period (eg, <7 days).
Tracheostomy has become one of the most commonly performed procedures in the intensive care unit (ICU), yet there still exists considerable uncertainty regarding its preferred technique, indications, and timing. Between 6% and 20% of patients requiring mechanical ventilation will receive a tracheostomy,1-3 including a large proportion of patients requiring prolonged mechanical ventilation, accounting for up to one-third of all ventilator days.4,5 The use of the procedure also appears to have increased over time,6 possibly due to the emergence of percutaneous dilational tracheostomy, which has made the procedure more convenient to perform at the bedside.7 Determining and refining the appropriate indications for tracheostomy are likely to become increasingly important as more patients survive the acute phase of critical illness and as pressures increase on critical care providers to facilitate patient flow through critical care areas.
INDICATIONS FOR TRACHEOSTOMY
Tracheostomy may be considered for a variety of different situations in critically ill patients, but the underlying rationale for the procedure may be simplified to three general indications (Table 46-1). The first is to establish or maintain a patent airway in a patient who has upper airway obstruction or who is incapable of adequate airway protection. The second is to assist with the delivery of positive pressure ventilation in patients with respiratory failure, in an effort to facilitate weaning from mechanical ventilation by reducing dead space and decreasing airway resistance, or to reduce sedative requirements by providing a more comfortable conduit to receive mechanical ventilation. The third is to facilitate clearing of secretions in patients with a need for ongoing pulmonary toilet.
Selected Examples of Indications for Tracheostomy