Page 2359 - Cote clinical veterinary advisor dogs and cats 4th

1166.e4 Tracheal Stent Placement

it to be longer than the fully deployed
measurement on the packaging.
VetBooks.ir larynx is not tolerated and causes discomfort
• Placement of the stent within the carina or
and worsening of clinical signs.
• Stent migration is more likely if stent is sized
inappropriately.
• Stent fracture: common long-term
complication
• Infection (airways, lungs): stent interferes
with mucociliary apparatus clearance at least
until the airway epithelium can grow over the
stent, potentially contributing to infection.
• Inflammation/tissue webbing is more likely if
stent is inappropriately sized; tissue webbing
can occlude the lumen of the stent.
Procedure
• The patient is anesthetized and intubated
with an appropriately sized endotracheal
tube. If the tube is smaller than 5.5 Fr, the
stent delivery device will not fit down the
endotracheal tube, and the patient will have
to be extubated for stent placement.
A • The patient is positioned in lateral recum-
bency under fluoroscopy and a measurement
catheter is placed into the esophagus within
the red rubber catheter using fluoroscopic
guidance.
• The cuff on the endotracheal tube is deflated,
and the endotracheal tube is pulled back with
fluoroscopic guidance until it is within the
proximal trachea, immediately distal to the
larynx, at which point the cuff is reinflated
gently.
• With the measurement catheter in place, the
trachea is distended to its maximal length
and diameter with a positive-pressure breath
of 20 cm H 2 O, and images are obtained
to measure the length and diameter of the
trachea along its distance.
• Measurements are made using the measure-
ment catheter as a means of calibrating the
measurement tool in the imaging software.
• The distal end of the stent should be located
at least 1 cm proximal to the carina, whereas
B the proximal end should not be closer than
1 cm distal to the larynx.
TRACHEAL STENT PLACEMENT A 12-year-old Yorkshire terrier before (A) and after (B) stent placement. • The appropriate stent width is chosen by
adding 10%-20% to the maximal diameter,
and the length is determined by measure-
ments, as well as the shortening chart
provided by the manufacturer.
• Endotracheal tubes (variety of sizes) • The person placing the stent must have • After the appropriate stent size has been
• Measuring catheter expertise in measurement to determine the determined, the stent is opened in a sterile
• Sterile lubricant appropriate-sized stent; this is perhaps the manner, and both ports are flushed with
• Sterile saline most crucial aspect of placement. saline to lubricate the delivery device.
• Fluoroscopy or standard radiographs • A variety of appropriate-sized stents must • To ensure proper function of the delivery
• Red rubber catheter be available for use. device, a small portion of the stent can
be deployed before placement and then
Anticipated Time Possible Complications and re-sheathed.
30-45 minutes with measurement process Common Errors to Avoid • The delivery device can be fed down the
• Inappropriate placement/sizing can lead existing endotracheal tube if it is large
Preparation: Important to worsening of clinical signs rather than enough to accommodate the device. If not,
Checkpoints improvement. the endotracheal tube is removed, and the
• It is vital that pet owners understand the ○ Make sure to take account of stent length patient is intubated with the delivery device.
goals, capability, limitations, and possible as well as diameter. Incomplete opening of • Passage of the delivery device down the
adverse outcomes. the stent to its maximal diameter will cause trachea is visualized using fluoroscopy. When

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