Tracheostomy

What is a tracheostomy?

There are increasing numbers of patients, both in hospital and the community, who have tracheostomy tubes. A tracheostomy provides direct access to the trachea by surgically making an opening in the neck. Once an opening is made it needs to be maintained, which is by tracheostomy tube, of which there are several types.

Tracheostomy is used in two broad types of conditions:

• Acute setting - usually in an emergency to obtain an airway and in ventilated patients who are having difficulty weaning off the ventilator.

• Chronic or elective setting - usually when the patient is to be ventilated for the longer term.

Indications for a tracheostomy¹

Comparison of tracheostomy and endotracheal intubation²

Prolonged ventilatory stay is the most common indication for tracheostomy in critically ill patients. Up to 24% of mechanically ventilated patients in ICU undergo tracheostomy. Tracheostomy, however, has not shown to have any clear-cut benefits, in terms of mortality or laryngotracheal complications, when compared to translaryngeal intubation.

Tracheostomy has been conventionally recommended for patients requiring ventilator for more than 21 days, and endotracheal intubation is recommended if ventilatory stay is less than 10 days.

When compared to translaryngeal intubation, tracheostomy is associated with less sedation, better patient comfort, and reduced work of breathing, aiding in faster weaning from a ventilator.

Types of tracheostomy tubes³

• Plastic or silver - silver tubes do not have an inner tube and need to be changed every 5-7 days (compared with every 30 days with some plastic types).

• Cuffed or uncuffed - cuffed tubes protect the airway and tend to be used in ventilated patients.

• Fenestrated or unfenestrated - these tubes may or may not be cuffed. They have a hole in the outer cannula which means that air can pass from the lungs and up to the vocal cords and also the mouth and nose. Patients can thus breathe normally and cough secretions out of the mouth, and it helps voicing. Fenestrated tubes tend not to be used in children.⁴

• Double or single cannula - double cannulae have an inner and an outer tube. The inner tube reduces the lumen of the outer tube meaning that respiratory effort is increased but the outer tube means that the stoma stays open.

How is a tracheostomy performed?

Tracheostomy can be performed in theatres (open surgical tracheostomy) or at the bedside (percutaneous dilatational tracheostomy), the latter being common on intensive care units (ICUs). A meta-analysis has concluded that percutaneously dilated tracheostomy is the procedure of choice in acute ICU patients.⁵

Surgical tracheostomy⁶

• The patient is supine with head extension and under general anaesthesia.

• Incision is 2-3 cm from the second tracheal ring down.

• Divide the thyroid isthmus if needed.

• Make a hole between the third and fourth tracheal rings, removing the anterior portion of tracheal ring.

• Tracheostomy tube is inserted.

Percutaneous tracheostomy⁶

• Percutaneous placement of a tracheostomy is performed using guide wires and dilators.

• Guidewire is placed between the first and second tracheal ring.

• Gradually, the hole size is increased using dilators of varying sizes which are passed over the guide wire.

• This can be performed blindly in experienced hands but often is aided by the use of a bronchoscope.

There are various other methods also available, both for surgical and for percutaneous dilatational tracheostomy.⁶

A Mini-Trach® is a tracheostomy tube of a smaller diameter that is passed through the cricothyroid membrane. It is usually employed during emergency situations when intubation fails.

A Cochrane review concluded that:⁷

• When compared to surgical tracheostomies, percutaneous tracheostomies significantly reduce the rate of wound infection/stomatitis (moderate quality evidence) and the rate of unfavourable scarring (low quality evidence).

• In terms of mortality and the rate of serious adverse events, there was low quality evidence that non-significant positive effects exist for percutaneous tracheostomies.

• In terms of the rate of major bleeding, there was very low quality evidence that non-significant positive effects exist for percutaneous tracheostomies.

• However, because several groups of participants were excluded from the included studies, the results of the meta-analysis were limited and could not be applied to all critically ill adults.

Complications^{8 9 10}

Immediate

• Haemorrhage - eg, from thyroid isthmus.

• Hypoxia.

• Trauma to recurrent laryngeal nerve.

• Damage to the oesophagus.

• Pneumothorax.

• Infection.

• Subcutaneous emphysema.

Early

• Tube obstruction or displacement.

• False passage formation.

• Pooling of secretions, leading to aspiration and lower respiratory tract infection (LRTI).

• Aspiration.

• Bleeding from the tracheostomy site.

• Infection.

Late

• Airway obstruction with aspiration.

• Damage to larynx - eg, stenosis.

• Tracheal stenosis.

• Tracheomalacia.

• Aspiration and pneumonia.

• Fistula formation - eg, tracheo-cutaneous or tracheo-oesophageal.

Care of a patient with either a short- or long-term tracheostomy^{3 4}

Stoma care

• Meticulous care towards hygiene and asepsis is necessary.

• Remember that the skin surrounding the stoma is also prone to irritation.

• There may also be other factors which may alter skin integrity - eg, radiotherapy.

• In double cannulae, the inner cannula will need to be removed to be cleaned (usually just with warm water and then left to air dry).

• The area should be cleaned with normal saline and barrier cream applied to the local skin (cotton wool should be avoided).

Tracheostomy tube care

• Tubes need to be cleaned - as above.

• For cuffed tracheostomy tubes, the pressure should be measured twice daily and maintained between 15-30 cmH₂O (15-25 cmH₂O for children).

Communication

• Losing one's voice can be very traumatic, both for patients and for carers.

• Speaking valves can be used in the short term and computerised methods can be used for longer-term solutions.

• The involvement of speech and language therapists is vital.

Swallowing and nutrition

• Problems with swallowing are caused by a number of factors, including the underlying illness, pressure on the oesophagus, lack of cough to remove secretions, etc.

• There is a risk of aspiration if oral feeding takes place; cuff inflation does not necessarily prevent this.

• There should be a multidisciplinary approach to nutrition with the early involvement of dieticians and speech and language therapists.

• Attention to oral hygiene is also needed.

Suctioning

• Remove fenestrated tubes before suctioning and replace with a plain tube.

• Use the lowest pressure needed (usually <120 mm Hg and definitely not beyond 200 mm Hg). For non-adults the following pressures are recommended: 60-80 mm Hg for neonates, 80-100 mm Hg for children and 80-120 mm Hg for adolescents.

• Suctioning should only be performed for less than 10 seconds at a time in adults and not longer than 5 seconds in non-adults.

Humidification

• The normal humidification and air filtration system is bypassed if a tracheostomy is in situ.

• Keep patients well hydrated - otherwise secretions will become thicker and are more likely to be retained. This can lead to infection and thus healthcare professionals need to be vigilant to markers of developing infection.

Patients and carers will need to be educated as to the above so that patients who will need the tracheostomy in the community can be safely and effectively managed. This applies both to children and to adult patients.

Short-term tracheostomy

As the patient improves and becomes less dependent on the ventilator, the tracheostomy can be plugged for longer durations. Similarly, once the cuff can be deflated, the patient can begin to speak if the opening is occluded. Usually this takes time and patients need lots of support.

Eventually, patients can manage without the tracheostomy and it can then be removed. Once a tracheostomy is removed the stoma usually heals over with time, although a scar often remains.