Page 341 - Clinical Small Animal Internal Medicine

31 Canine Chronic Bronchitis 309

VetBooks.ir Box 31.3 Airway sampling techniques hood in retrieving a representative cytology from more
Cytologic samples can be obtained from the airway via a
tracheal wash, blind bronchoalveolar lavage, or with
bronchoscopy. areas of the airway.
Transtracheal wash (TTW) is best suited for tolerant Endotracheal wash (ETW) is commonly performed in
medium‐ or large‐sized dogs. This technique should be smaller patients, patients that are less amenable to restrain,
avoided in brachycephalic breeds, and obese patients brachycephalic breeds, and obese patients.
where easy palpation of the trachea is limited.
● ETW is performed by briefly anesthetizing the dog with
TTW is performed in unsedated or lightly sedated dogs. propofol then performing a clean intubation with a sterile
●
After aseptic preparation of a small area over the cervical endotracheal tube. Lubricating gel should not be used.
●
trachea or larynx and a local anesthesia block is per- ● In a sterile fashion, a 5–8 Fr catheter is fed through the
formed, a through‐the‐needle catheter is passed through endotracheal tube and sterile saline is infused and
the cricothyroid ligament or between tracheal rings; the reaspirated. Alternatively, a modified technique using
catheter is fed down the trachea (beveled edge down). suction, a Lukens specimen container, a three‐way stop-
Two to three aliquots of 5–10 mL 0.9% sterile saline are cock, and a red rubber or Argyle feeding tube can be
●
flushed into the trachea, and promptly retrieved. Retrieval used (Figure 31.4a,b).
volume is typically about 50%, and the remaining fluid is ● 0.9% saline aliquots of 3, 5, and 10 mL are used for dogs
rapidly absorbed from the airway. <5 kg, 5–15 kg, and >15 kg, respectively.
Collection of a diagnostic sample is facilitated by a A sterile collection cup may be used to collect any addi-
● ●
patient’s ability to cough resulting in an increased likeli- tional samples that may be expectorated.

(a)

(b)

Figure 31.4 Equipment set‐up for a modified technique to perform bronchoalveolar lavage or endotracheal tube lavage using
suction, a Lukens specimen container, a three‐way stopcock, and a red rubber or Argyle feeding tube.