Tracheostomy Primer, by Dr. Steven Rosenblatt and Dr. Nikolaus
Wolter.
My name is Steven Rosenblatt, and I'm
a pediatric otolaryngologist.
The goal of this lecture is to provide some basic background
information about tracheostomies.
At the end of this video, the viewer
should be able to understand basic airway anatomy
relevant to a tracheostomy, indications
for a tracheostomy, how a tracheotomy is performed,
the working parts of a tracheostomy tube,
and common tracheostomy accessories you may encounter.
Basic Airway Anatomy.
Normal respiration requires air to pass through the nose
and mouth into the pharynx, through the larynx,
and then down to the lower-respiratory tract.
Obstruction at any of these sites
can lead to respiratory distress.
And depending on the site of obstruction,
can prevent intubation and necessitate a tracheostomy.
A brief discussion of the basic anatomy of the upper airway
is important for understanding complications
relating to tracheostomy management.
The larynx itself is divided into three contiguous areas--
the supraglottis, which includes the epiglottis,
false vocal folds, and arytenoid cartilages,
the glottis, which includes the true vocal folds themselves,
and the subglottis, or region immediately
below the true vocal folds.
The subglottis is the only part of the airway that
is made of a complete cartilaginous ring that is
called the cricoid cartilage.
The trachea is made of a series of U- or C-shaped cartilages.
The pediatric larynx differs from the adult larynx
in several important ways.
First, the pediatric larynx is funnel shaped,
with the most narrow point being the subglottis
within the cricoid cartilage.
Whereas in an adult, the narrowest point
is the glottis itself.
Another important difference between the adult
and pediatric larynx is that the laryngeal structures
overlap in an infant, almost like sections of a telescope.
The hyoid bone sits over the thyroid cartilage,
and the thyroid cartilage overlaps the cricoid.
This will stretch out with age.
But in an infant, the hyoid bone can
make palpation of the thyroid cartilage landmarks difficult.
And because the thyroid cartilage overrides
the cricothyroid membrane, cricothyrotomy is generally not
possible in children.
Finally, the pediatric larynx sits higher and more anterior
in the neck than in an adult patient.
Indications for a Tracheostomy.
Oftentimes, you'll hear the words
tracheotomy and tracheostomy used interchangeably.
However, a tracheotomy is the act
of making a hole in the trachea, whereas a tracheostomy
is the actual opening created from the skin to the trachea.
In general, there are three main indications
for performing a tracheotomy--
one, acute or chronic upper airway obstruction,
two, prolonged mechanical ventilation,
or three, the need for pulmonary toilet.
Understanding why your patient has a tracheostomy
is critical for dealing with tracheostomy complications.
In an emergency, patients who undergo tracheotomy
for prolonged mechanical ventilation or pulmonary toilet
can usually be reintubated from above if necessary.
However, if the indication was upper airway obstruction,
careful consideration needs to be given to the situation
to determine the best course of action.
Performing a Tracheotomy.
During the procedure itself, the layers of the neck
are carefully identified and separated,
creating a tract down to the trachea.
Prior to finding the trachea, the thyroid gland
is usually encountered.
The surgeon may choose to move the gland out of the way
or divide the gland to expose the trachea.
In a child, two stay sutures are usually
placed through the second and third cartilaginous rings
on either side of the trachea where the tracheostomy incision
will be made.
The purpose of the stay sutures will become apparent
in the next video.
A vertical midline incision, parallel
to the long axis of the trachea, is
made through the second and third cartilaginous rings.
And the tracheostomy tube is inserted with an obturator.
The obturator is similar to a stylet
that sits within the tracheostomy tube itself.
The thin, rounded end of the obturator
protrudes just slightly beyond the tip
of the tracheostomy tube itself and facilitates insertion.
Once the tracheostomy tube has been inserted,
the obturator is removed and the position
is confirmed by CO2 return or by direct visualization
with a bronchoscope.
Typically within three to five days,
this tract will scar and mature.
But prior to this, reinsertion of the tracheostomy tube
must be done carefully and by experienced personnel
to avoid inserting the tracheostomy tube
in between these layers, creating a false passage.
Tracheostomy Tubes.
A tracheostomy tube is a curved ventilation tube
that sits within the trachea below the level of the larynx.
The tracheostomy tube usually has
two main components-- the tube itself
that serves as the airway, and the faceplate.
The faceplate has two flanges that
allow the tracheostomy tube to be
secured in place by neckties.
The faceplate also usually has information
printed on the surface that describes the type
and size of tracheostomy tube.
Multiple models and different brands are available,
but generally speaking tracheostomy tubes
can be divided into two broad categories.
The first is the presence or absence of a cuff.
Cuffed tubes have an inflatable balloon
at the distal end similar to an endotracheal tube.
When this cuff is up, all of the air and pulmonary secretions
pass through the tracheostomy tube itself.
A cuffed tracheostomy tube is necessary
if a patient requires mechanical ventilation in order
to maintain a closed circuit.
The second broad category is the presence or absence
of an inner cannula.
Inner cannulas are not commonly found
in neonatal or pediatric tracheotomy tubes,
but will often be seen in older children
with adult-sized tubes.
Common Accessories.
You may encounter various tracheostomy accessories,
like a Swedish nose or speaking valve.
The Swedish nose is a type of HME,
or heat-moisture-exchanger, which
helps make up for the fact that the nose and mouth are
no longer humidifying and warming inspired air.
Small sponges capture expired moisture
and help to warm and humidify inspired air.
A speaking valve, or Passy-Muir valve,
functions as a one-way valve at the end
of the tracheostomy tube.
When breathing in, air passes through the tracheostomy tube.
But when breathing out or speaking,
the valve is forced closed and the air
travels around the tracheostomy tube and out of the mouth.
It is important that a speaking valve must never
be used with an inflated tracheostomy tube
cuff, as air trapping will occur and patients
can develop a tension pneumothorax,
which can be fatal if not recognized promptly.
Lastly, a tracheostomy tube must be secured snugly,
and is typically done so with a soft Velcro tie.
Loose ties can lead to movement of the tracheostomy tube
within the stoma.
This can cause bleeding, granulation tissue formation,
or displacement of the tracheostomy tube
into a false passage or out of the trachea.
These complications are easily avoidable by ensuring a snug
fit at all times.
This concludes our instructional video
regarding tracheostomy basics.
In this video, we reviewed basic airway anatomy relevant
to a tracheostomy, indications for a tracheostomy, how
a tracheotomy is performed, the working
parts of a tracheostomy tube, and common tracheostomy
accessories you may encounter.
Thank you for watching.
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