Contin Educ Anaesth Crit Care Pain-2008-Regan-31-5

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Tracheostomy managementKate Regan MRCP FRCA

Katharine Hunt FRCA

The use of tracheostomy has increased over

recent years. Traditionally, it was confined to the

emergency management of upper airway

obstruction; more recently, indications have

extended to include prolonged mechanical venti-

lation, chronic respiratory insufficiency, failure

of airway protective reflexes, management of

excessive secretions, and obstructive sleep

apnoea.1

Percutaneous tracheostomy at the

bedside in intensive care is increasingly popular.

Compared with an open surgical procedure,

there are similar rates of complications2

and

further studies are ongoing to determine the

optimal timing of tracheostomy for patients on

intensive care units (http://www.tracman.org.uk).

The techniques of percutaneous tracheost-

omy insertion are becoming increasingly fam-

iliar to anaesthetists and have been the subject

of a previous review in this journal.3

The

ongoing management of tracheostomies both in

the ICU and the ward environment may be less

familiar. A range of specialties may be

involved in the management of such patients,

including ENT and maxillofacial surgeons,

speech and language therapists, physiothera-pists, and critical care outreach nurses.

Anaesthetists are often called to troubleshoot

and give advice.

This article describes the different types of

tracheostomy tube that may be encountered and

how to manage emergencies (e.g. blocked tra-

cheostomy tube). It also considers more general

aspects of the ward-based management of tra-

cheostomy tubes.

Tracheostomy tubes

Tracheostomy tube size is described most com-

monly in terms of the internal diameter (ID) of

the tube at its narrowest point which, together

with the outer diameter (OD), is marked on the

tube flange or cuff. A tube corresponding to the

size of the patient’s trachea should be selected;

too small a tube will lead to increased airway

resistance and an increased work of breathing

during spontaneous respiration;1

in addition,

suctioning of secretions may be more difficult.

Increased cuff pressures will also be required to

create a seal in smaller tubes, which may

increase the risk of tracheal mucosal injury.

Too large a tube may be difficult to insert and

lead to problems with insufficient leakage past

the cuff when cuff deflation is attempted during

weaning.

The curvature and length of the tracheost-

omy tube should also be appreciated when

selecting a tube for any given patient, as it will

vary between different designs and manufac-

turers. While the trachea is essentially straight,

some tube designs have a pronounced curvature

that can lead to the tracheostomy tip becoming

compressed against the anterior tracheal wall

causing partial obstruction. A longer proximal

length may be required in obese patients, while

additional distal length maybe useful in patients

with anatomical abnormalities of the tracheal

wall, e.g. tracheomalacia.

Single and double cannula tubes

Traditionally, a single lumen tube is passed

into the trachea (Fig. 1, left side). The tube is

supplied with an obturator in the lumen whichaids insertion and is removed before use. A tra-

cheal cuff allows separation of the lungs from

pharyngeal secretions, although it is recognized

that some leakage of secretions past the cuff

may still occur. Uncuffed tubes are available

for patients requiring long-term tracheostomy

who have reasonable bulbar function but are

unable to clear their secretions.

Double cannula tubes are supplied with an

inner tube, which can be removed independently

of the outer tube (Fig. 1, right side). In the event

of tube obstruction, this inner tube can be

removed and cleaned, thus reducing the inci-

dence of potentially life-threatening compli-

cations. This means that this is often the tube of

choice especially for ward-based weaning.

However, it should be noted that the work of

breathing through a double cannula tracheostomy

is increased due to the reduction in ID of the

tube. In addition, some designs need the inner

tube to be in situ to allow connection to the

15 mm ventilator tubing. Double cannula tubes

may be fenestrated or unfenestrated (Fig. 2).

Key points

Tracheostomy use hasincreased as techniques andequipment have improved.

Tracheostomy tubes areincreasingly encountered inthe ward environment; arange of specialists may beinvolved in theirmanagement.

A range of different sized

and shaped tubes areavailable. They may be singleor double cannula tubes.Double cannula tubes maybe fenestrated orunfenestrated.

Anaesthetists are oftenasked to advise aboutweaning and tube removal.They may also be called if apatient is in extremis tomanage a blocked ordislodged tracheostomy.

Patients may be able tospeak and swallow foodsafely with a tracheostomytube in situ.

Kate Regan MRCP FRCA

SpR in Anaesthesia and Intensive CareMedicine University College Hospital

London

UK

Katharine Hunt FRCA

Consultant AnaesthetistNational Hospital for Neurology and

Neurosurgery Queen Square

London WC1 N 3BGUK

Tel: þ44 207 829 8711Fax: þ44 207 829 8734

E-mail: [email protected] /[email protected] (for correspondence)

31doi:10.1093/bjaceaccp/mkm049Continuing Education in Anaesthesia, Critical Care & Pain | Volume 8 Number 1 2008

& The Board of Management and Trustees of the British Journal of Anaesthesia [2008].All rights reserved. For Permissions, please email: [email protected]



Fig. 1 Different types of tracheostomy tubes. On the left is a single lumen, adjustable phlange tracheostomy; on the right is a double cannula tracheostomy.

Fig. 2 An unfenestrated (above) and fenestrated (below) inner tube.

Tracheostomy management

32 Continuing Education in Anaesthesia, Critical Care & Pain j Volume 8 Number 1 2008



Fenestrated and unfenestrated tubes

Fenestrated tubes have an opening in the posterior part of the outer

tube. If the tube is cuffed, the fenestration lies above the cuff.

Deflation of the cuff during spontaneous respiration (with the fene-

strated inner tube in place) allows air to pass caudally through the tra-

cheostomy lumen and fenestration, as well as around the

tracheostomy tube, and up through the larynx. This encourages

maximal airflow through the upper airways during speech and also

allows assessment of the normal route of air passage during prep-

aration for decannulation. If positive pressure ventilation is required,

the unfenestrated inner tube should be inserted, to prevent air leak

above the cuff. There are different designs of fenestrations; single and

multiple fenestrated tubes are available.

Other types

Adjustable tracheostomy tubes have a movable flange such that the

length of the tracheostomy tube from skin surface to trachea can

be adjusted at the bedside (Fig. 1, left side). There is a locking

mechanism on the flange to maintain the correct tube length.

These tubes are used in patients with atypical anatomy, where

there is a long depth from skin surface to trachea (e.g. obesity). At

present, these tubes are only manufactured with a single lumen;

hence, there is a greater risk of tube obstruction by secretions and

they should always be used with humidified oxygen. It should also

be noted that some of these tubes may be reinforced; therefore,

because of the metal within the tube, it may not be safe for use

with lasers or magnetic resonance imaging.

Low profile tracheostomy tubes are available, and are often

reserved for patients who have undergone tracheal or laryngeal

surgery. Custom made tubes are available in silicone or silver, and

may be useful when a tracheostomy is required for long-term or

permanent use.

The mini-tracheostomy tube is smaller (typically, 4 mm ID)

and can be inserted through the cricothyroid membrane. It allows

rapid access to the trachea and is designed to permit the entry of a

size 10 suction catheter. As such, it may be inserted either to

facilitate the suctioning of excessive secretions or as part of a

weaning regimen. Since it is uncuffed, and its diameter does not

permit mechanical ventilation, it should not be used in patients

with inadequate airway reflexes or respiratory drive.

Changing tracheostomy tubesTracheostomy tubes may need to be changed periodically; there is

little evidence to guide practice. After 10 days, the stoma has

usually formed a defined tract, and changing the tracheostomy tube

is usually straightforward. It is common practice to electively

change single lumen tubes 10– 14 days after initial insertion, to

prevent the development of granulation tissue around the tracheost-

omy tube and tube blockage from excessive secretions.

Furthermore, many manufacturers recommend that a double

cannula tube should not remain in situ for more than 30 days for

similar reasons; many units change this type of tube monthly.

Other indications for elective tube change include substituting for

a different type of tube to facilitate weaning or speech and tube

damage or obstruction.

The insertion tract is often poorly defined until 7–10 days afterformation; therefore, difficulties in changing tracheostomy tubes

prior to this time should be anticipated. Failure to re-cannulate or

the creation of a false tract is possible. Passing a bougie or airway

exchange catheter through the existing tracheostomy tube before

removing it may act as a guide into the trachea. A fibrescope can

be used to visually confirm tube position and facilities should be

readily available for oral tracheal intubation in the event of a pro-

blematic insertion. It should be noted that the oral route may not

be an option if the patient has undergone extensive oral, cervical

or laryngeal surgery, where there may be only a partial or no con-

nection between the oral cavity and the trachea.

The blocked tube

The anaesthetist is often called to manage a blocked tracheostomy

tube. While assessing the patient, oxygen should be delivered both

via a facemask and the tracheostomy. If the patient is not in extre-

mis, it may be preferable to transfer the patient to theatre, where

improved monitoring, fibreoptic equipment and surgical expertise

may be more readily available. It is important to establish whether

there has been recent surgery to the upper airway (including laryn-

gectomy), the previous grade of laryngoscopy (though it should be

appreciated that this may have changed as a result of recent

surgery or oedema), how long the tracheostomy has been in place,

and how difficult its initial insertion was. If the patient is in extre-

mis, the flowchart in Figure 3 is suggested as way of troubleshoot-ing the possible causes for the obstruction.

Weaning and decannulation

Most patients are suitable for weaning as their condition improves.

However, some patients require long-term tracheostomy tubes and

arrangements need to be made for their management within the

community. Before consideration for weaning, a multidisciplinary

assessment should be made, including assessment of the patient’s

gag and swallowing reflexes, and dependency on suctioning and

physiotherapy. Absolute requirements include a patent upper

airway, spontaneous cough, and ability to swallow secretions.

Assessment of swallow

The blue dye test has previously been advocated as a method for

assessing the patient’s ability to swallow secretions. A teaspoon of

water coloured with blue dye is given and respiratory sections from

the tracheostomy are monitored over 24 h. The appearance of dye

in the secretions implies inadequate swallowing reflexes. However,

there is growing evidence that the blue dye test has a high rate of

false positive results (i.e. clinical aspiration is not detected) and

the sensitivity of this test may be as low as 38%.4

It is therefore


Continuing Education in Anaesthesia, Critical Care & Pain j Volume 8 Number 1 2008 33



recommended that it is no longer used as the standard technique; it

has been replaced by bedside clinical assessment by speech thera-

pists, videofluroscopy, or fibre optic endoscopic evaluations of

swallow.

Weaning

While there are many different suggested strategies for tracheost-

omy weaning, there is no consensus on the optimal approach.

However, there is evidence that a systematic multi-disciplinary

approach improves likelihood of success.5

The aim of this

approach is to develop goals for the individual patient, monitor

ongoing progress and identify when further investigations may be

required.

Methods of weaning include increasing periods of cuff defla-

tion, the use of fenestrated tubes and speaking valves and the

downsizing or capping off of the tracheostomy tube prior to final

removal. In our institution, progressive cuff deflation until the

patient has tolerated this for a 24 h period, followed by capping off

of the tracheostomy tube overnight is preferred. If the patient does

not tolerate this, the cuff should be re-inflated and further

investigations, including ENT referral to ensure patency of the

upper airway, may be required.

Humidification

Tracheostomy bypasses the natural humidification of the upper

airway and breathing dry gases can lead to damage of the respirat-

ory cilia and epithelium. Secretions may dry out and lead to block-

age of the tracheostomy lumen. For this reason, it is essential that

all tracheostomy patients receive humidified, and preferably

heated, gases if on supplemental oxygen. If breathing room air, aSwedish nose device incorporating a heat and moisture exchange

filter can be employed.6

Speech

Communication difficulties are a significant problem in patients

with a tracheostomy and various methods have been developed to

facilitate speech. To attempt speech, patients need to be able to tol-

erate periods of cuff deflation without respiratory compromise and

without the risk of gross aspiration.

Fig. 3 Suggested algorithm for tracheostomy patients with breathing difficulties.


34 Continuing Education in Anaesthesia, Critical Care & Pain j Volume 8 Number 1 2008



In a spontaneously breathing patient, the simplest method of

allowing speech is through cuff deflation, allowing air to pass

around the tracheostomy and through the vocal cord apparatus. A

fenestrated tube will allow maximal airflow, as described pre-

viously. If the tube is too big to allow sufficient air to pass, redu-cing the size of the tube may be considered.

A one-way speaking valve can also be used with the tracheost-

omy tube to maximize speech. This allows air to be entrained

through the tube during inspiration. The valve then closes during

expiration such that exhaled air must pass through the natural

airway and vocal cords to exit the lungs, thus aiding phonation.6

A

speaking valve may also be employed in some ventilator dependant

patients. Studies have shown that speech for these patients’ acts as

a psychosocial boost, allows patients to communicate, aids consent

and may also help in reinstating smell and taste. Before employing

this technique, the rate and work of breathing, as well as oxygen

and ventilator dependency, must be assessed. In general, F IO2. 0.4,

positive end expiratory pressure .5 cm H2O and high levels of pressure support negate the use of speaking valves and cuff deflation

in ventilator dependant patients.

Feeding

It is often stated that the presence of a tracheostomy tube prevents

patients eating. The weight of the tube restricts laryngeal elevation

during swallowing and the cuff may protrude into the oesophagus.

However, the literature remains inconclusive and many centres

now advocate trial feeding regimens with tracheostomy tubes in

situ if the patient has low oxygen and respiratory support require-

ments and does not drool.

References

1. Epstein SK. Anatomy and physiology of tracheostomy. Resp Care 2005; 3:

476–82

2. Silvester W, Goldsmith D, Uchino S, Bellomo R, Knight S, Seevanayagam S,

Brazzale D, McMahon M, Buckmaster J, Hart GK, Opdam H, Pierce RJ,Gutteridge GA. Percutaneous versus surgical tracheostomy: a randomised

controlled study with long term follow up. Crit Care Med 2006; 8:

2145–52

3. Eggbert SM, Jerwood C, Percutaneous tracheostomy. CEACCP 2003; 3:

139–42

4. Lewarski JS. Long term care of the patient with a tracheostomy. RespCare 2005; 4: 534–37

5. Hunt K, McGowan S. Tracheostomy management in the neurosciences: asystematic, multidisciplinary approach. Br J Neurosci Nurs 2005; 11:

122–25

6. Hess DR. Facilitating speech in a patient with a tracheostomy. Resp Care

2005; 4: 519–25

Please see multiple choice questions 26–28


Continuing Education in Anaesthesia, Critical Care & Pain j Volume 8 Number 1 2008 35

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