27. Procedures

One of the oldest surgical procedures, a tracheostomy is performed in order to gain access to the airway when endotracheal intubation is either contraindicated or impossible.

Indications

Tracheostomy can be performed electively or emergently (Box 27.1.1).

Any lesion or abnormality causing upper-airway obstruction may require a tracheostomy.

If prolonged mechanical ventilation is expected, changing from an endotracheal tube to a tracheostomy may have benefits (described in section on Timing).

Complications

The most severe complication of tracheostomy is failure to establish an airway, resulting in hypoxemia, brain damage, or death.

Box 27.1.1 Indications for tracheostomy

Elective

• Upper airway obstruction (impending)

• Neurologic

• Pulmonary

Emergency

• Upper airway obstruction (acute)

• Tumor

• Trauma

• Failed intubation

Percutaneous tracheostomy tubes can become obstructed by the posterior membranous trachea, or rarely, placement can cause perforation of the posterior wall of the trachea.

Massive hemorrhage due to a tracheoartery (innominate artery) fistula is a rare but devastating complication:

Often there is a sentinel bleed of 100 to 300 mL, which then stops.

This should be recognized and a cardiothoracic surgeon should be consulted immediately. CT angiography or bronchoscopy may be needed to confirm the diagnosis.

The incidence is less than 1% in several studies, likely due to the low-pressure cuffs used today.

See Box 27.1.2 for a complete list of complications with tracheostomy.

Equipment

Tracheostomy tubes can be

Plastic (polyvinyl chloride or silicone) or metal (silver or stainless steel)

Uncuffed or cuffed

Unfenestrated or fenestrated

A cuff provides an airway seal and reduces aspiration of secretions.

Box 27.1.2 Complications of tracheostomy

• Failure to establish an airway

• Accidental extubation

• Subcutaneous emphysema

• Pneumothorax

• Pneumomediastinum

• Aspiration

• Bleeding

• Infection

• Tracheal granulations

• Subglottic stenosis

• Tracheal stenosis

• Tracheoarterial fistula

• Posterior tracheal wall perforation

Modern cuffs are typically low pressure and high volume, and cuff pressures should not exceed 25 cm H₂O.

Fenestrated tubes have an additional opening in the posterior portion above the cuff, which should permit upper airway airflow and facilitate speech.

Other specifications include the outer diameter, inner diameter, and length (angle or curved, standard or extra length, fixed length, or adjustable flange).

Adjustment in horizontal or vertical length can be helpful in patients with large necks or tracheal anomalies, respectively.

Tubes can have a single or dual cannula:

Dual-cannula tubes possess an inner cannula and will not connect to a ventilator without it.

The supposed advantage is quicker and easier cleaning of the inner tube to prevent obstruction by secretions.

Evidence that this decreases pneumonia is lacking.

Disadvantages include a smaller internal diameter, which may increase the work of breathing and paradoxically trap secretions.

Tracheostomy tubes can typically be changed after 5 to 7 days of insertion, when there is a mature tract from the skin to the airway.

If a tracheostomy tube becomes dislodged before there is a mature tract, no immediate attempt should be made to replace the tube, and the patient should first be orotracheally intubated to control the airway.

Procedure

Bedside percutaneous tracheostomy has become an alternative to standard operative tracheostomy performed at the bedside or in the operating room

Successful performance of the bedside percutaneous procedure is related to expertise of the operator and ancillary personnel. It appears to be safe when performed by surgeons or well-trained intensivists.

In comparison to standard operative tracheostomy, bedside percutaneous tracheostomy offers several advantages: it requires less time to perform, it is less expensive, and it is typically performed sooner (because an operating room doesn’t have to be scheduled).

Complication rates are similar with both the procedures.

Relative contraindications to percutaneous tracheostomy include age under 15 years, uncorrectable bleeding diathesis, gross distortion of neck, clinically suspected tracheomalacia, infection in soft tissues of neck, obesity and/or short neck which obscures landmarks, or inability to extend neck (cervical spine instability or fusion).

Percutaneous tracheostomy has been performed successfully by skilled operators in patients who were very old, morbidly obese, had a history of previous tracheostomy, or had thrombocytopenia.

Outcomes after Tracheostomy

There are several putative benefits of subglottic ventilation (Box 27.1.3).

Overall, the current evidence supports consistent morbidity benefits of tracheostomy, however no mortality benefits have been proven.

Box 27.1.3 Putative benefits of tracheostomy

• Decrease in ventilator dead space

• Decreased airway resistance

• Ease of suctioning

• Reduced orolabial and laryngeal trauma

• Increased patient comfort

• Reduced requirement for sedation

• Increased patient mobility

• Shorter duration of mechanical ventilation

• Ability to transfer spontaneously breathing patients to non-ICU settings

• Ease of tube replacement (once tract matures)

• Increased ability for the patient to communicate

• Variable capacity for oral intake of nutrition and medication

Other Considerations

Timing of Tracheostomy in Endotracheally Intubated Patients

Many physicians believe patients should not be ventilated via an endotracheal tube for longer than 3 weeks unless they are unstable or unlikely to benefit from tracheostomy.

This view is based upon observations that tracheostomy enhances nursing care, improves patient comfort, and improves patient communication.

There is conflicting data about whether early tracheostomy improves outcomes.

The best evidence suggests early tracheostomy may improve short-term clinical outcomes such as ventilator days and ICU days, but at a cost of surgical and stoma-related complications.

A recent multicenter randomized controlled trial looked at early (7 days) versus late (14 days) tracheostomy and found a decrease in ventilator days, a decrease in ICU days, and a trend toward less pneumonia in the early group. No difference in survival was seen, nor did early tracheostomy change any outcomes at 1 year.

Based on current data, the timing of tracheostomy should be individualized to each patient and must reflect his or her anticipated clinical status, readiness to wean from the ventilator, and possible benefits from tracheostomy.

Emergency tracheostomy can usually not be achieved as quickly as cricothyroidotomy, but may be appropriate in patients with an urgent need for a definitive airway that cannot be orotracheally or nasotracheally intubated, but are still oxygenating and ventilating.

Weaning and Decannulation

When there is no longer a need for airway protection and mechanical ventilation, patients may have their tracheostomy tubes downsized.

In addition, a fenestrated or cuffless tube will allow increased airflow through or around the tube, permitting the tracheostomy tube to be “capped-off” and facilitating speech.

A one-way valve, such as a Passy-Muir valve, will also permit laryngeal airflow during expiration and enable speech.

Specific weaning strategies are institution dependent: some consider it after the tracheostomy tube has been capped for 48 hours, whereas others consider it once a speaking-valve is tolerated.

It is important to never place a speaking-valve or cap a nonfenestrated tube with the cuff inflated, as this causes complete airway obstruction.

It is standard practice when decannulating a patient to simply remove the tracheostomy tube and allow the wound to heal by secondary intention.

If the skin is closed primarily and the trachea remains open, any air leak that ensues can cause complications with subcutaneous emphysema, pneumomediastinum, and pneumothorax.