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394 PART 4: Pulmonary Disorders

the average tooth-to-carina distance, which is 28 cm in the average male when a patient will be unable to clear their airway secretions for a long
and 24 cm in the average female). Tooth-to-carina distance varies; a period of time. Finally, tracheostomy is frequently used to facilitate
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tube taped at 24 cm at the lip might be in perfect position for the average liberation from mechanical ventilation.
180-cm male, but might not even be in the trachea of a very tall patient. Tracheostomy has several benefits in patients who will require long-
Correct positioning of the ETT is difficult to verify clinically and requires term mechanical ventilation. It allows easier and safer access to the
fiberoptic bronchoscopy or a chest radiograph for confirmation. 49,50 mouth, which allows improved oral hygiene. It is substantially more
In spite of assertions that it should never happen, esophageal intu- comfortable than translaryngeal intubation, so the need for both anal-
bation remains an inevitable complication of airway management. In gesics and sedation may be significantly reduced. Specially designed
theory, it should be quickly recognized and the offending tube removed tracheostomy tubes allow for speech and even normal eating in patients
expeditiously. In practice, it will occur in circumstances in which who are either continuously or intermittently ventilated. There was
auscultation of the breath sounds is difficult and where endotracheal a time when patients underwent tracheostomy after only very brief
intubation cannot be confirmed with capnography, including patients periods of translaryngeal intubation and mechanical ventilation (eg,
with severe bronchospasm (especially children), and in adults in full 7-10 days). In contemporary practice, the decision to perform a trache-
cardiopulmonary arrest. 51 ostomy on a patient should not be motivated as much by the time that
Gastric aspiration that occurs around the time of intubation in the has already elapsed on mechanical ventilation as by the amount of time
ICU can cause pneumonia and precipitate ARDS; it occurs approxi- it can be foreseen that they will require mechanical ventilation. If the
mately 4% of the time. In less controlled settings, such as in trauma patient will obviously require ventilation for the coming weeks, then it
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patients, aspiration may occur in up to 30% of patients around the time is quite reasonable to perform a tracheostomy for both their safety and
they are intubated. The application of cricoid pressure and manipula- comfort. 60,61 Patients at high risk for the complications of translaryngeal
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tion of the airway with the patient awake are the two most effective intubation, such as diabetics, may benefit from earlier tracheostomy.
strategies to avoid this problem. Tracheostomy has the great benefit of reducing the dead space in the
A variety of tissue injuries are associated with airway management in ventilation circuitry, resulting in substantially greater alveolar ventila-
the ICU setting. 53-56 These injuries are more likely to occur in uncoop- tion for any given minute ventilation. This benefit may be of critical
erative patients, seizing patients, and patients with anatomically difficult importance in patients whose strength is very closely matched to their
airways. Dental injury and tooth fragment aspiration remain compli- requirement for minute ventilation, and who might not otherwise be
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cations of airway management. Tracheal and esophageal lacerations can easy to liberate from the ventilator. The ease of reinstituting mechanical
also occur. At least some bleeding is likely to occur in coagulopathic ventilation, and the wide bore and short length of tracheostomy tubes
patients and in patients with friable tissues. The vocal cords and ary- are also of benefit in these circumstances.
tenoid cartilages can also be traumatized during intubation. Prolonged
tracheal intubation can also impair swallowing, which increases the risk ■ PERCUTANEOUS VERSUS SURGICAL TRACHEOSTOMY
of aspiration in these patients after extubation. Residual muscle paraly- There is a large and growing literature that clearly demonstrates that
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sis is an important risk factor for aspiration in perioperative patients, percutaneous and surgical tracheostomy are equally successful and safe
and perhaps in critically ill patients as well. 59 in competent hands. 62-64 Interestingly, the sum of the patients in all of
A variety of cardiac complications may occur around the time of the prospective studies published thus far is less than 600, limiting the
airway manipulation. Myocardial ischemia can be precipitated by statistical power of inferences about rare complications, such as death,
the stress response to airway interventions. The amount of ischemia pneumothorax, and posterior tracheal wall perforation, but certainly
precipitated can be minimized with adequate topical anesthesia and allowing the conclusion that the success rates and overall complica-
by matching the sedation given to the degree of stimulation created. tion rates of the two procedures are very similar. Mortality of either
Ventricular premature beats are a common consequence of the stress procedure is now less than 1%, which is significantly lower than that
response in the setting of airway instrumentation. Ventricular tachycar- reported in older literature. When performed at the bedside in the ICU,
dia and ventricular fibrillation can occur in patients susceptible to these both percutaneous and surgical tracheostomies are significantly less
arrhythmias. Bradycardia can also occur, particularly in young patients expensive and easier to arrange than a tracheostomy in the operating
with high vagal tone. room. The difference in cost between the two procedures performed at
Death occurs around the time of endotracheal intubation in approxi- the bedside is small, and likely to be outweighed by other institutional
mately 3% of critically ill patients. In some patients, issues of airway factors and considerations.
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management will contribute to the sequence of events that result in A variety of techniques for percutaneous tracheostomy have been
death; nevertheless, an expeditious intubation averts death in the vast described and are in widespread use. Briefly, after appropriate sedation,
majority of patients. the patient’s neck is extended to open the tracheal interspaces. The skin
over tracheal interspaces below the cricoid cartilage is then anesthe-
TRACHEOSTOMY tized, prepped with an appropriate cleansing agent, and draped in sterile
fashion. A 2-cm horizontal incision is made, and the strap muscles of
The role of tracheostomy continues to evolve in critically ill patients. The the neck are bluntly dissected along the midline down to the trachea.
improved design of ETTs and careful attention to sedation has minimized The existing tracheal tube is then withdrawn to a position just below the
the traumatic consequences of prolonged intubation, making transla- vocal cords. A needle is then inserted into the trachea (usually under
ryngeal intubation for weeks both safe and tractable. On the other hand, bronchoscopic guidance), and a wire threaded into the tracheal lumen.
improved techniques for performing tracheostomy and the increasing The tract is then mechanically dilated, and an appropriately sized tube
ability to perform a tracheostomy at the bedside have made tracheostomy inserted into the trachea. Commercially available kits are now available
safer and more available than it has been previously. In spite of these that replace multiple dilators with a single dilator (eg, Blue Rhino PDT™
improvements, tracheostomy continues to have immediate and long- from Cook Critical Care, Bloomington, IN), which may save time and
term complications that intensivists must be prepared to manage. reduce the risk of the procedure as well. Two of the advantages of the
■ INDICATIONS FOR TRACHEOSTOMY percutaneous technique are the minimal sharp dissection involved, and
the use of dilation to create the tract for the tracheostomy tube, both of
The least controversial indication for tracheostomy is upper airway which limit the bleeding associated with the procedure.
obstruction, especially long-term or permanent airway obstruction. The literature about percutaneous tracheostomy clearly documents
Tracheostomy is also widely accepted as preferable to transglottic intuba- that it can be accomplished successfully and safely in the hands of
tion for long-term mechanical ventilation. Tracheostomy is also indicated competent practitioners. Some techniques incorporate bronchoscopic

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