Page 73 - BSAVA Manual of Canine and Feline Head, Neck and Thoracic Surgery, 2nd Edition

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

mattress sutures placed parallel to the long axis of the Prognosis: Resolution occurs in 60–83% of dogs and cats
pinna and avoiding blood vessels. Overtightening must be after surgical drainage. Owners should be warned that
VetBooks.ir left at the incision to allow continued drainage of the suffering thickening, longitudinal contraction or abnormal
cosmetic results can be variable, with some animals
avoided because postoperative swelling is likely. A gap is
carriage of the pinna. Success for the surgical incision
haematoma, and the ear is bandaged down across the neck
or up over the head to prevent self-trauma and absorb
than 7–10 days and when the OE or underlying cause of
additional fluid. technique is best when drainage is maintained for more
Other options for treatment include: fenestration of the aural pruritus is treated. Some surgeons recommend con-
medial pinna over the haematoma, using a carbon dioxide current use of systemic corticosteroids (prednisolone:
laser to make multiple drainage holes; passive drainage 1 mg/kg q12h for 2 weeks, then q24h for 2 weeks, then
with a teat cannula placed through a stab incision at tapered) to help reduce inflammation and predisposing
the apex of the haematoma, or a through-and-through causes of pruritus and otitis.
Penrose drain; and continuous suction drainage with a
closed system (Figure 5.3). Fenestrated silicone drains
have been placed with a two-incision technique, first to Other pinnal conditions
introduce the drain into the haematoma cavity from the Pinnal neoplasia
convex surface of the pinna and then to exit it at the base
Various tumour types may occur on the pinna of dogs
of the pinna through the cervical skin (Pavletic, 2015). The
drain is sutured in place, attached to a commercial suction or cats, including histiocytomas, plasmacytomas, mast
cell tumours, melanocytomas/melanomas, papilloma, hae-
bulb (e.g. Jackson Pratt) and left for 18–21 days; during
this time the dog wears an Elizabethan collar but does not mangioma and squamous cell carcinoma. Squamous cell
require bandaging of the pinna. carcinoma of the pinna is most often encountered in white
cats as a sequela to chronic actinic damage of the skin.
• To make a small continuous suction drain, the syringe Although round cell tumours of the pinna most often
adaptor end of a 19 G butterfly catheter is removed and the present as discrete nodules, squamous cell carcinoma
remaining tube is fenestrated to a length slightly shorter (and its precursors, actinic keratosis and carcinoma in situ)
than the haematoma cavity. Fenestrations are made by may present as erythema, swelling, crusts and erosions
folding the tube over and cutting off a corner of the fold or ulcers. Pre surgical evaluation of tumours of the pinna
to make a hole less than 50% of the tube’s diameter. may include fine-needle aspirates for cytological assess-
• The fenestrated portion of the tube is then inserted into ment, incisional biopsy for histopathology and staging
the haematoma cavity through a stab incision on the procedures such as aspirates of local lymph nodes and
concave surface of the ear. thoracic radiographs.
• The stab incision is closed around the tube with a The type of surgical procedure planned (e.g. marginal
purse-string or mattress suture, and the tube is excision, partial pinnectomy or radical pinnectomy) will
secured to the pinna with a fingertrap pattern or depend on the tumour type. Surgical resection is not typi-
butterfly tape and mattress sutures. cally recommended for canine histiocytomas because the
• The needle end of the tube is inserted into a vacuum vast majority will regress within 3 months (Clifford et al.,
blood tube. If the vacuum blood tube loses its suction 2013). The outcome of surgical resection of pinnal
because of air introduction, it can be ‘recharged’ by neoplasms depends on tumour type and behaviour. For
using a needle and syringe to suction the air out of the example, dogs with low-grade (grade 1 or grade 2) pinnal
blood tube. mast cell tumours have been shown to have a prolonged
• The ear is bandaged against the dog’s head or neck, survival time following excision, whilst dogs with high-
and the vacuum tube is changed as needed to maintain grade (grade 3) mast cell tumours had a more guarded
continuous suction and compression of the haema- prognosis and a median survival time of 10 months follow-
toma cavity. ing surgical excision (Schwab et al., 2014). A recent study of
• The tube is usually removed no sooner than 1 week cats with pinnal squamous cell carcinoma reported a better
after placement, and then the bandage is left in place response to surgical excision (radical pinnectomy with or
for another week. without total ear canal ablation) in cats with actinic keratosis
or squamous cell carcinoma restricted to the distal portion
of the pinna than in cats with tumour extension to the proxi-
mal portion of the pinna and ear canal (Demirutku et al.,
2012). In that study, three of the eight cats had relapse of
the tumour at the surgical site.

Pinnectomy for squamous cell carcinoma: For subtotal
pinnectomy, the pinna is amputated with curved Mayo
scissors at least 1–2 cm from the visible margin of the
mass, ulceration or crusting. Haemostasis is achieved
with cautery. The skin of the convex and concave sur-
faces is then sutured together. For complete pinnectomy,
the skin is incised near the base along the convex surface
of the ear and allowed to retract away from the pinna
cartilage. The cartilage and the skin of the concave
surface of the ear are transected with scissors. If skin
apposition results in tension, the caudomedial edge of
Auricular haematoma treated with oral steroids and a
5.3 the wound can be elevated and advanced, or a single
continuous suction drain made from a fenestrated butterfly
catheter and vacuum tube. After the drain was placed, the dog’s ear was pedicle advancement flap is developed, to allow suture
a ed to its head ith tape and a bandage to prevent head shaking. closure of the wound.

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