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Tracheostomies
providing verbal communication for the tracheostomized patient. Speech while
on mechanical ventilation requires adequate cardiopulmonary reserve, so the
patient should be hemodynamically stable before attempting phonation.
Traditional mechanical ventilation with an inflated cuff delivers precise
volume ventilation but does not allow for speech since exhaled airflow is diverted away from the vocal cords and through the expiratory limb of the ventilator. The ensuing detailed discussion offers a balance of various options that
allow proper tracheostomy tube selection, adjustment of ventilator settings, and
speech.
Leak Speech With a Deflated Tracheostomy Tube Cuff
For the patient requiring long-term invasive positive-pressure ventilation, leak
speech with a deflated, or partially deflated, tracheostomy tube is often the
quickest and safest way to achieve phonation. Tube size becomes an important choice when attempting phonation. The tube’s outer diameter must allow
enough airflow between the tube and the tracheal wall for air to reach the vocal
cords and achieve phonation. A tube that is too small, however, may allow too
much airflow past the tracheostomy tube and make adequate ventilation difficult when the cuff is deflated. Furthermore, a small tube may also create undesirably high peak airway pressures on the ventilator and impede adequate
suctioning.
Achieving phonation in the chronically ventilated patient through leak
speech usually requires a fine balance between adequate phonation and adequate ventilation. The tracheostomy tube cuff volume can usually be adjusted
to achieve this balance if full deflation cannot be tolerated.
Equally important is coaching patients on how their speaking and breathing will be altered when the cuff is deflated. A patient’s understanding of the
central role of glottic control in balancing breathing and speech is essential.
This can present a challenge to patients, who are likely unfamiliar with upper
airway anatomy and may be overwhelmed by their new dependence on a mechanical ventilator. Often, patients in the early stages of this process allow too
much air to escape through their upper airway. This may lead to shortness of
breath, feelings of upper airway dryness, and hypercapnia. The patient’s realization that vocal cord adduction can direct more air into his or her lungs often
gives a much-needed feeling of control to the fearful patient experiencing air
hunger. Coordination between the speech language pathologist and respiratory
care practitioner is essential in this endeavor.
The careful adjustment of ventilator settings must accompany the leak
speech approach. Phonation is limited by the airflow during the inspiratory
cycle of the ventilator. Speaking during inspiration is, of course, opposite of what
one normally does and, thus, requires relearning a new speech mechanism. The
key components that ensure adequate and minimally interrupted phonation
are a trialed ventilator rate, longer inspiratory times, and larger delivered tidal
volumes. PEEP at varying settings has also been reported to improve speech
during mechanical ventilation with cuff deflation (Hoit, Shea, & Banzett, 1994).
It is important that the clinician not rely too much on a patient’s glottic control for delivery of adequate volume. The size of the tracheostomy tube and the
degree of cuff inflation, along with the ventilator settings, should be such that
acceptable ventilation is achieved regardless of a patient’s glottic manipulation.
Chapter 12 Rehabilitation and Recovery
Unlike using an inflated cuff, where volume delivery and arterial pCO2 levels
can be precisely tailored, the clinician will usually have to accept a range of
clinically acceptable values once phonation with a deflated cuff is pursued.
Mechanical Ventilator Adjustment to Balance
Speaking and Breathing
A mechanical ventilator set to deliver 8 breaths per minute, with an inspiratory time of 1 second, will only allow for approximately 8 seconds of speaking
time per minute, which is usually unsatisfactory. A mechanical ventilator set
at 12 breaths per minute, with an inspiratory time of 2 seconds, will allow for
24 seconds per minute of phonation, tripling the potential speaking time. It is
very important, however, not to let the desire for adequate speech conflict with
the other goals of mechanical ventilation. For example, higher ventilator rates,
which might be preferable for speech, require smaller tidal volumes to maintain
a desired pCO
tion of atelectasis. Some authors have advocated the use of the pressure-control
ventilation mode to automatically guarantee delivered volumes with leak speech
(Gilgoff, Peng, & Keens, 1992). This approach may have merit, but our experience with modern, portable ventilators is that alarm settings can be difficult to
adjust to safely accommodate this mode.
level. However, smaller tidal volumes interfere with the preven-
2
333
Leak Speech With Deflated Tracheostomy Tube Cuff
and One-Way Valve
This method of allowing for speech in the chronically mechanically ventilated
patient may allow for a more satisfactory speech pattern. This technique essentially prevents the patient’s exhaled gas from following the normal pathway
through the expiratory limb of the ventilator circuit. Thus, all exhaled gas flow
must exit through the patient’s upper airway. Optimally, the patient is taught to
close his or her glottis during the inspiratory phase of the ventilator, receive the
full ventilator breath, and then exhale and speak during the expiratory cycle.
Hence, a normal pattern of speech is approximated. Keeping inspiratory pressures and flow rates modest will help the patient achieve this holding of the
breath during inspiration. In contrast to leak speech without a one-way valve,
this method should employ shorter inspiratory times and longer expiratory
times, since speech occurs primarily during exhalation and all exhaled gas must
be expelled before the next breath is delivered. Ventilator settings (e.g., mode,
rate, inspiratory pressure, and flow rate) should be optimized by a methodical
trial-and-error approach.
Precautions.
encouragement, and careful monitoring.
■
It is vital that the tracheostomy tube cuff never be reinflated while using the
one-way valve, as the patient will not be able to exhale.
■
Choosing the proper tube size and type becomes very important as well
as excluding any upper airway lesions that may obstruct airflow. This
method requires the clinician to carefully assess if exhaled gas can flow
Patients unfamiliar with this method initially require instruction,
334
Tracheostomies
through the upper airway before the next breath is delivered. A failure
to allow complete exhalation may lead to air trapping with consequences
for increased intrathoracic pressures, decreased venous return, and
hypotension.
■
Humidification can become problematic with prolonged use of this technique, since an HME attached distal to the one-way valve renders it
ineffective.
It is a good idea to assess the risks and benefits of the two options early on
with each patient, and then choose one method. Switching from cuff deflation
alone to cuff deflation with a one-way valve can be confusing to the patient and
caretakers alike.
Other Options for Speaking While on a Mechanical Ventilator
Three types of tracheostomy tubes address the potential problems encountered
with speech using a deflating cuff. One design has long been on the market,
one has recently been introduced to the market, and one is described in literature but is presently unavailable. Each will be briefly discussed in the following
section.
Categories of Tracheostomy Tubes
Speaking Tracheostomy Tubes.
available but do not appear to have gained widespread acceptance. The design
of these tubes is essentially the same as tubes with a subglottic suction port.
A feature of these tubes is that a port is attached to an external flow of gas
rather than to suction. This flow of gas is delivered above the cuff and moves
through the upper airway to facilitate phonation. One limitation of this design
is the possibility for the misdirection of airflow if this opening is improperly
aligned within the tracheal lumen. Without proper alignment, air often exits
primarily through the tracheal stoma. Additionally, this small line is prone to
clogging with secretions, often rendering it useless. The need for an external
gas source also creates limitations for the mobile, ventilator-dependent patient. This external supply of gas for phonation typically comes from portable
air or oxygen cylinders or from a small air compressor. Patients who cannot
use their hands to occlude this port are dependent on a caregiver for speech.
Should a clinical scenario dictate the continuous inflation of a tracheostomy
tube cuff, however, this tube design may be considered if phonation is to be
attempted.
Blom Tracheostomy Tube System.
recently introduced and promises another option for speech in the ventilatordependent patient who needs an inflated cuff. In addition to a fenestrated outer
cannula, this tube has a special inner cannula that allows delivery of the exhaled portion of the ventilator breath through the vocal cords. This design obviates the need for an external gas source as well as manual occlusion of the air
delivery port. The potential benefit of this system is guaranteed volume delivery, which could not otherwise be achieved with a deflated cuff. The mechanics
Speaking tracheostomy tubes have long been
The Blom tracheostomy tube system was
Chapter 12 Rehabilitation and Recovery
of this device must be fully appreciated by those using it. Training and experience are necessary to safely use this tube.
335
Voice Tracheostomy Tube.
able, promises to allow speech while preserving predictable volume ventilation
(Nomori, 2004). Its clever design involves fenestrations placed at the cuff site in
a single-cannula tube, which results in cuff inflation during mechanically delivered inspiration. During exhalation, the elastic cuff deflates, directing approximately 40% of the exhaled volume through the vocal fold and allowing speech.
A newly designed device, though presently unavail-
Characteristics of Tracheostomy Tubes
Size.
The size of the tracheostomy tube will have an impact on airflow resistance
and cuff-related complications. A small inner diameter may cause excessively
high ventilating pressures and increase resistance to spontaneous breathing. A
high-volume, low-pressure cuff, if mismatched to the tracheal diameter, may act
as a high-pressure cuff (Guyton et al., 1991).
Ease of Changing.
support—such as the patient with a high-level spinal cord injury—it is critical that the tube be easily reinserted should it become dislodged. A highvolume, low-pressure cuff can occasionally be difficult to reinsert because, even
when deflated, it takes up considerable space and may not easily pass through
a stoma that has closed tightly around the outer cannula. By contrast, a lowvolume, high-pressure cuff (e.g., the Bivona TTS or Arcadia CTS) can typically
be reinserted with much less difficulty and trauma. This can be advantageous
for the patient who is a difficult tracheostomy tube change and is critically dependent on mechanical ventilation. Complications from long-term or improper
use of these cuffs have been described previously.
In the patient who is completely dependent on ventilator
Dual- Versus Single-Cannula.
cannula. However, the desirable features of some single-cannula tubes may outweigh the advantage of an inner cannula. One advantage is the increased inner
diameter of a single-lumen tube relative to the outer diameter. Another advantage is the increased flexibility of many single-cannula tubes that accommodate
variations in anatomy.
With a single-cannula tube, attention should be given to proper humidification and a prescribed tube-changing schedule to avoid obstruction and a narrowing of the tube’s inner diameter. By comparison, an obstruction of a dual-cannula
tube can be easily remedied by changing the inner cannula. However, a clogged
single-lumen tube may only be remedied by changing the entire appliance.
The ideal tracheostomy tube should have an inner
Evaluating the Need for Relief of Upper Airway Obstruction
When the clinician decides to progress the tracheostomy tube and allow the
patient to breathe through his or her native upper airway, it is essential to exclude upper airway lesions, particularly in patients with long-term tubes. At
minimum, a simple bedside evaluation should be performed to assess patency
336
Tracheostomies
of the upper airway; however, a fiber-optic exam may be of value before decannulation (Law et al., 1993). Informing patients about these evaluation options is
essential to minimize anxiety and fear. Coughing and minor discomfort as well
as a sensation of difficulty breathing may all be encountered.
The initial step should be clearing secretions above and below the cuff. In
a patient with a strong cough, the cuff may be slowly deflated to allow the patient to expel the respiratory secretions. In a patient with a weaker cough, it is
helpful to deliver a large breath with a manual ventilator while simultaneously
deflating the tube cuff. The large exhaled volume will facilitate blowing the accumulated secretions above the cuff into the oropharynx. It may take a few
moments for the patient to adjust to the deflated cuff. The clinician should then
occlude the tube digitally to assess airflow through the upper airway and look
for the following signs of increased airway resistance:
■
Stridor
Prolonged inspiratory phase ■
Use of accessory muscles of inspiration ■
Intercostal retractions ■
Subjective complaints ■
It is important to remember that any of these signs and symptoms could be
attributed to an oversized device, which does not permit sufficient airflow around
it. An oversized tube would typically have a larger than 10 mm outer diameter
in an adult. In some adults, a smaller tube may contribute to significant airway
resistance, especially a completely deflated high-volume, low-pressure cuff.
Eliminate the Tracheostomy Tube as a Source of the Problem
In order to exclude the tube as the cause of obstruction, the clinician must remove the tracheostomy tube and reassess airflow. Only clinicians experienced
in replacing airways should remove airways. Initial preparation for the proce-
dure includes having immediately available a tube of similar size, a tube one
size smaller, and a cuffless tube. The latter two can usually be placed if the
original tube proves difficult to reinsert.
When the tube is removed, the clinician should cover the open stoma securely with sterile gauze, apply finger pressure, and assess for upper airway
resistance. If no airway resistance is noted, the clinician can reasonably assume
that tracheostomy type or size is the problem.
Eliminate Soft Tissue Upper Airway Obstruction
as a Source of the Problem
Should the obstruction remain, one additional maneuver can be performed in
select patients. While one clinician covers the tracheal stoma, another can perform a chin lift. If this maneuver eliminates the obstruction, soft tissue might
be the cause. At this point, the tracheostomy tube of choice should be replaced
and left uncapped, and a subsequent plan should be discussed. Upper airway
endoscopy is warranted to verify causes of obstruction. In the patient with mild
Chapter 12 Rehabilitation and Recovery
soft tissue upper airway obstruction, it may be appropriate to cork the tube while
providing supervision for speech therapy sessions. Another option is the use of a
one-way valve, which bypasses the soft tissue obstruction. Patients with a history
of stroke and TBI have a high frequency of soft tissue upper airway obstruction.
Conclude the Bedside Clinical Evaluation
If bedside evaluations reveal no upper airway problem, the clinician may proceed to capping trials, once an appropriate tube has been chosen, in accordance
with safety measures as dictated by the patient and institution. If signs of upper
airway obstruction persist, the clinician should replace the tracheostomy tube
and leave it uncapped. The patient should then be evaluated by an otolaryngologist before the tube is progressed. The incidence of obstructive airway lesions in patients with long-term tracheostomies has been reported as high as
67% (Law et al., 1993). Commonly acquired lesions include tracheal granuloma,
tracheomalacia, tracheal stenosis, and vocal cord and laryngeal dysfunction.
337
Traumatic Brain Injury, Stroke, and Upper Airway Obstruction.
paired by stroke, TBI, or anoxic brain injury often manifest soft tissue upper
airway obstruction in the acute rehabilitation setting. In fact, increasing evidence links obstructive sleep apnea (OSA) syndrome as an independent risk
factor for stroke (Martinez-Garcia et al., 2005; Yaggi et al., 2005). Soft tissue
upper airway obstruction due to loss of pharyngeal muscle tone may occur during sleep or waking hours. Since an open tracheostomy tube is curative for the
obstruction, the clinician must cautiously progress the tracheostomy tube in
this patient population.
The primary supportive mode for patients with soft tissue upper airway
obstruction is nasal CPAP. With this therapy, positive pressure throughout the
ventilatory cycle acts to start the upper airway and relieve soft tissue obstruction. The main limitation to CPAP is the patient’s level of alertness and tolerance. It is advisable to attempt nasal CPAP support before decannulation. If the
patient does not tolerate the CPAP device, the tracheostomy tube can be left
open. If the patient tolerates nasal CPAP, a tube suitable for corking must be fitted for proper titration of CPAP level. Following the decannulation of a patient
using nasal CPAP, a period of suboptimal CPAP support is expected and should
be compensated for while the stoma is closing. Positive airway pressure applied nasally can escape through an open tracheal stoma; therefore, the stoma
should be sealed with an occlusive dressing until it closes. Discharge planning
arrangements should accommodate the use of nasal CPAP.
Newer devices such as auto-titrating CPAP are increasingly available in the
acute rehabilitation setting and beyond. It is always advisable to consult with a
sleep disorder team for diagnosis, optimal choice of CPAP titration device, and
monitoring of CPAP support.
Patients im-
Considerations for Transitioning Tracheostomy Tubes
The progression of tracheostomy tubes warrants consideration of several important factors, including presence or absence of cuffs, structure of the tubes,
338
Tracheostomies
and technique of downsizing. A description of the impact of those factors is
provided in the following sections.
Cuffless Tracheostomy Tubes
Cuffless tracheostomy tubes offer an advantage during corking or capping maneuvers because they offer less airway resistance. Regardless, they may be less
than ideal with nocturnal ventilation needs and significant bronchial hygiene
problems.
TTS Tracheostomy Tubes
The Bivona TTS tracheostomy tube has a low-volume, high-pressure cuff. Consequently, the clinician must pay attention to cuff pressure to avoid tracheal
wall damage from long-term exposure to high cuff pressures.
Fenestrated Tracheostomy Tubes
Fenestrated tracheostomy tubes can be used to transition toward decannulation. Their potential advantages during this transitional phase have been introduced elsewhere (see chapters 6 and 11); however, the frequent challenges of
properly positioning these tubes warrant careful observation of the following:
■
Fenestrated tubes should be properly fit so the fenestration is located
centrally within the tracheal lumen to allow airflow between the upper
and lower airways.
■
Proper positioning of the fenestration should be periodically checked by
removing the inner cannula or cap and illuminating the opening with a
light source. No tissue should compromise the window.
■
Changes in patient position, coughing, and too much or too little gauze
under the tube are factors that alter the placement of the fenestration
within the airway.
■
A window in the outer cannula often allows tissue growth into the opening.
One-Way Valves
One-way valves (see chapter 6, Table 6.3) can play a role in the progression of
an artificial airway. They allow inspiration through the tube and direct exhalation through the upper airway. Therefore, an upper airway obstruction should be
evaluated prior to the use of a one-way valve. In an attempt to allow patients to
phonate, clinicians often use one-way valves with improper tubes, which do not
allow easy exhalation. Therefore, a completely deflated cuff and a tube of appropriate size must be used to allow easy airflow between tube and the trachea. Any
signs of air trapping should signal an end to the use of a one-way valve until further assessments of tube size and upper airway patency are carried out. Patients
can usually be safely capped without a one-way valve as long as the cuffless
tube is of proper type and size. The advantage of routine capping over the use
Chapter 12 Rehabilitation and Recovery
of one-way valves is the restoration of normal upper airway humidification of
inspired air. Prolonged use of one-way valves without supplemental humidification leads to the formation of thick, inspissated secretions and atelectasis. However, some conditions—such as mild, soft tissue obstruction in the neurologically
compromised patient—might benefit from using a one-way valve.
Downsizing Tracheostomy Tubes
Downsizing tracheostomy tubes can play an important role in the progression
toward capping and decannulation; thus, the following implications should be
considered:
■
Increased work of breathing: An increase in airway resistance will occur
when the patient breathes through a smaller tube, particularly if the cuff
is inflated.
■
Adequate removal of secretions: With tube downsizing, the size of the
suction catheter will also need to be downsized so it is not a source of
obstruction. However, a smaller suction catheter may not be adequate to
evacuate thick secretions.
■
Appropriate monitoring of cuff pressure: When used to achieve a proper
seal, an overinflated low-pressure, high-volume cuff has the effect of a
high-pressure cuff. Thus, close attention to all cuff pressure is important,
particularly when repeated inflation is necessary.
339
Discharge to Home
The majority of tracheostomized patients can be decannulated during their
acute care stay; however, there are always those who cannot. Cox, Carson, Holmes, Howard, and Carey (2004) reviewed a 10-year database of 144,875 patients
who required mechanical ventilation in the state of North Carolina. Of 49,872
patients who required intubation for more than 4 days, nearly 10,000 underwent
a tracheostomy. Not only did the rate of tracheostomy increase 200% over the
10-year duration, but also significantly fewer tracheostomized patients were
discharged home.
Patients who use oxygen in the hospital must undergo a desaturation trial
within 2 days prior to discharge. Patients are monitored with a pulse oximeter
at rest and when the oxygen supplement is removed. If there is no desaturation
at rest, the patient is tested during exertion. If the patient desaturates to 88% or
less on exertion, he or she qualifies for home oxygen use. Detailed qualifications
for the use of long-term oxygen are provided by the Centers for Medicare and
Medicaid Services (http://www.cms.hhs.gov/MedicareApprovedFacilitie/02_o2
trial.asp).
Patients who transition to home with tracheostomy tubes warrant careful planning for transition of care. The American Thoracic Society published
guidelines that help chart the long-term care of these patients (ATS, 2000; DeLeyn et al., 2007).
340
Tracheostomies
Discharge Planning
The Extended Care Information Network (ECIN) is a national database that
connects patients with vendors. Hospitals and vendors subscribe to this service.
When patients require medical equipment and services at home, the discharge
planner matches the patient’s insurance coverage with that of appropriate subscribing vendors. Patients must be given a choice of vendors. Discharge planners
should be given a list of the required supplies in order to procure them from
appropriate vendors long before the date of discharge. The discharge planner or
case manager is usually responsible for investigating what is covered by the patient’s insurance company, including home care services and supply companies.
All equipment should be delivered in the home prior to discharge. It is advisable to have emergency equipment delivered to the patient’s bedside for
availability during transport. These essential supplies include a manual resuscitation bag for ventilation, a suction machine, suction catheters, and two extra
tracheostomy tubes (same size as the patient’s and one size smaller).
The entire family should be educated to provide routine as well as emergency care. Routine care includes suctioning, cleaning the inner cannula, cleaning the stoma, and changing the tracheostomy tube ties or holder. While doing
routine care, patients and family members should be taught to observe color
and odor changes to secretions, the presence of fever, an increase in respiratory rate, or bleeding and report these signs to their care provider. Emergency
care includes the management of respiratory distress—most likely a mucus
plug. In addition to calling the emergency response system, family members
should be taught emergency procedures such as basic life support and the
Heimlich maneuver.
When a patient with a tracheostomy is discharged home, a back-up plan
should be in place to mobilize prompt and appropriate assistance. Local emergency response personnel should be notified in advance about patients with tracheostomies and their addresses. They should be provided with pertinent medical
history and shown how to access the house. This will give paramedics advance
notice of what to expect upon arrival, and they will be able to save precious minutes in an emergency, especially since the patient will likely be unable to speak.
It is also important to make the power company aware that vital emergency
equipment—such as suction machines, oxygen extractors, and ventilators—is in
the home. In this way, patients and caregivers can be notified in advance of any
planned power interruptions.
Home Discharge Checklist
Teach patient and family about tracheostomy care and managing emer- ■
gencies
■
Organize planned discussion among family members regarding shared
responsibilities or schedule for care
■
Order supplies
Arrange for home nursing supervision of care ■
Complete electrical assessment ■
Complete oxygen desaturation test to determine requirement for home ■
oxygen
Chapter 12 Rehabilitation and Recovery
Care for Patients at Home
There are several factors to consider when a patient is discharged home. Is the
patient physically able to manage the care of the tracheostomy? Does the patient live alone, or is there someone at home who can assist? When a discharged
patient with a tracheostomy is otherwise healthy and strong, he can easily resume a relatively normal life. If the patient is weakened because of disease
or disability, destinations other than home should be considered. A ventilator dependent patient will likely require professional assistance, and consideration
should be given for the patient’s placement in a specialized facility. This care is
a daunting task but should not overcome a sense of duty, responsibility, or love
for a family member. Normal home life is disrupted, and the focus of all activity becomes the care of the patient. There is no reprieve unless arrangements
are made for respite care. Clearly, one person cannot provide round-the-clock
care (Warren et al., 2004). Continuous professional care at home is a prohibitive out-of-pocket expense not covered by payors, whereas approximately 80%
of durable medical equipment cost is covered by Medicare and most insurance
companies.
Tracheostomy Care and Supplies at Home
341
Care and Cleaning.
at home is done with clean rather than sterile technique. Table 12.1 outlines
teaching points for tracheostomy care at home. Patients and caregivers should
be taught to clean or change the inner cannula at least twice per day, and more
often if necessary. Specific cleaning instructions depend on the type of tube.
Inner cannulas made of polyvinyl chloride can typically be cleaned using hydrogen peroxide, which is not recommended for metal or silicone tubes. The
In contrast to the hospital setting, care of the tracheostomy
Teaching Points for Routine and Emergency
12.1
Patients with a tracheostomy have a tendency to develop mucus plugs. ■
Use clean technique at home. ■
Check and clean the inner cannula at least twice per day (refer to the manufacturer’s ■
recommendations).
Clean the stoma with cotton swabs.
■
Change tracheostomy tube holder as needed. ■
Change entire tracheostomy tube every 2 months (refer to the manufacturer’s ■
recommendations).
Increase fluids as tolerated to keep secretions thin and mobile.
■
Suction as needed to remove secretions. ■
Minimize cuff pressure. ■
Add humidity as needed. ■
Tracheostomy Care at Home