Page 95 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery

Staphylectomy for elongated/overlong soft developmental abnormalities of the larynx such as under-
developed cartilages with chondromalacia and narrow
palate
VetBooks.ir The dog is positioned in sternal recumbency for soft glottic (cricoid) dimensions (Rutherford et al., 2017) play an
important role in the aetiopathogenesis of the syndrome.
More research into the specific primary and secondary
palate resection (see Operative Technique 6.2). A bar is
placed over the front of the surgery table from which the
upper jaw is suspended by placing gauze, tape or band- laryngeal abnormalities is needed, however.
Whether or not all brachycephalic animals with respira-
age material around the maxillary canine teeth. The pro- tory problems benefit from sacculectomy is controversial,
posed lateral levels of palate resection, the caudal and the benefit of sacculectomy in the overall outcome has
borders of the palatine tonsils when a minimal amount of not been assessed.
rostral retraction is applied to the tongue, are tagged with Medical management, including weight loss, exercise
two stay sutures. An Allis tissue forceps is placed on the restriction and drugs to reduce airway swelling (e.g.
caudal edge of the palate on the midline and used to pull glucocorticoids) or oedema (e.g. furosemide), can be
the palate rostrally. The palate is then resected in an arch attempted in animals with signs secondary to persistent
shape, making sure to remove more tissue medially than laryngeal collapse (Monnet and Tobias, 2012) and narrow
laterally. Resection can be performed with scalpel blades, laryngeal and tracheal dimensions. Patients that do not
scissors (Harvey, 1982b; Bright and Wheaton, 1983; respond to the first-stage surgical and medical manage-
Riecks et al., 2007), a carbon dioxide laser (Clark and ment may require sacculectomy, partial laser laryn-
Sinibaldi, 1994; Davidson et al., 2001; Riecks et al., 2007) gectomy or laryngeal tie-back; however, the effectiveness
or an electrothermal feedback-controlled bipolar sealing of these procedures for resolution of airway obstruction
device (Brdecka et al., 2009). However, as for resection of has not been extensively evaluated (Pink et al., 2006;
the nares, the use of laser and electrothermal devices is White, 2012; Monnet and Tobias, 2012). In the authors’
not recommended for staphylectomy by the authors: opinion, temporary as well as permanent tracheotomy
‘cold’ resection techniques are advised. After resection, procedures in brachycephalic dogs should be avoided if
the oropharyngeal and nasopharyngeal mucosa are possible because inherent tracheal hypoplasia, granula-
apposed using 1.5–2 metric (3/0–4/0 USP) monofilament tion tissue and scar formation, and increased loss of
rapidly absorbable suture material. rigidity as a result of this procedure significantly compli-
Serious complications of staphylectomy include death cate a successful outcome. In addition, breathing through
as a result of aspiration pneumonia, dyspnoea and cyan- a temporary as well as permanent tracheotomy site has
osis requiring tracheostomy, or failure to recover from been shown to lead to warming of cerebral arterial blood
anaesthesia (Harvey, 1982b; Lorinson et al., 1997; Torrez and the brain itself (Baker et al., 1974), adding to the
and Hunt, 2006). Less severe complications include cough- disturbed thermoregulation in these breeds.
ing, noisy respiration, and gagging and retching (Reiter and
Holt, 2012). The prognosis of dogs after soft palate resec-
tion is good to excellent in 90% of cases, especially in dogs
younger than 1 or 2 years of age (Harvey, 1982b; Poncet et Postoperative care
al., 2005; Riecks et al., 2007; Reiter and Holt, 2012). A
recent report (Liu et al, 2017), on the other hand, found that In general, after rhinoplasty and staphylectomy, dogs
younger animals may actually have a worse prognosis. should be observed and kept calm during recovery until at
However, age was only one of several factors influencing least 1 hour after extubation, which should take place only
outcome reported by this study and it also showed that when they are almost fully awake and consciously aware of
dogs undergoing modern multilevel surgery have a better the tube (Brainard and Hofmeister, 2012; Monnet and
prognosis than those under going traditional surgery. Tobias, 2012). The dog’s pulse, temperature, and respira-
tory rate and effort are monitored frequently. Food and
water are withheld only until complete recovery. Dogs are
Everted laryngeal saccules and laryngeal monitored for any gagging, retching or vomiting, stridor
collapse and development of dyspnoea. After recovery, dogs are
offered water and a small amount of soft food under
Traditionally, three different stages of laryngeal collapse supervision, and swallowing is carefully observed. After
are clinically recognized (Leonard, 1960; Pink et al., 2006;
laryngeal procedures, dogs must be observed in an inten-
Monnet and Tobias, 2012; Oechtering et al., 2016b; Liu sive care unit. If postoperative dyspnoea occurs, animals
et al., 2017). Stage I is relatively mild, consisting of laryngeal
are best heavily sedated (for 8–12 hours, with an additional
saccule eversion. In stage II, medial collapse of the cunei- dose of corticosteroids administered) and re-intubated
form process of the arytenoid cartilage as a result of lack of with a small tube. They can generally be successfully extu-
rigidity is seen. In stage III, the corniculate processes of the
bated and recovered uneventfully after this period.
arytenoid cartilages collapse, resulting in significant airway
obstruction (Leonard, 1960; Harvey, 1982a; Lorinson et al.,
1997; Pink et al., 2006; Huck et al., 2008; Monnet and
Tobias, 2012). This classification does not do justice, how- References and further reading
ever, to the wide range of laryngeal abnormalities seen in
the brachycephalic breeds and the breed-specific laryngeal Baker MA, Chapman LW and Nathanson M (1974) Control of brain temperature
anatomy. Most animals have some degree of eversion of the in dogs: e ects of tracheostomy. Respiratory Physiology 22, 325–333
saccules (i.e. the mucosa of the lateral ventricles), even in Brainard BM and Hofmeister EH (2012) Anesthesia principles and monitoring. In:
Veterinary Surgery: Small Animal, ed. KM Tobias and SA Johnston, pp. 248–291.
absence of obvious clinical signs (Kaye et al., 2015). In addi- Elsevier Saunders, St Louis
tion, pure stage II or III collapse is uncommon because Brdecka DJ, Rawlings CA, Perry AC and Anderson JR (2009) Use of an
most animals with more advanced laryngeal collapse dem- electrothermal, feedback-controlled, bipolar sealing device for resection of
the elongated portion of the soft palate in dogs with obstructive upper airway
onstrate a varying degree of collapse of both the corniculate
disease. Journal of the American Veterinary Medical Association 233,
and cuneiform processes. It seems logical that primary 1265–1269

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