Advanced Small Animal Surgery Midterm

What are the functions of skin?

Maintain hydration of tissues

Defense against environment

Vitamin D production

Sensory

Storage of water, fat, electrolytes, carbs, and proteins

Insulation

What are the three layers of the skin?

epidermis

dermis

hypodermis

layer of the skin composed of avascular tissue with a cuboidal/stratified epithelium and variable thickness depending on location

epidermis

layer of skin composed of hair follicles, glands, vascular plexus, lymphatics, nerves, and collagen that gives skin its viscoelasticity

dermis

layer of skin associated with the dermis mostly composed of fat and connective tissue that contains the panniculus

hypodermis

critically important landmark when performing reconstructive cutaneous surgery in dogs and cats as failure to identify and preserve it will lead to loss of blood supply and wound dehiscence

panniculus m. (aka platysma, cutanoeus trunci, supramammarius, preputialis)

panniculus fibers penetrate the ______ allowing voluntary movement of the skin

dermis

where is the panniculus muscle NOT present?

lower limbs

when undermining skin, always dissect ? the panniculus m.

under

vessels that run parallel to the skin and that serve as the skins blood supply which is unique to dogs and cats relative to humans

direct cutaneous arteries and veins

direct cutaneous arteries and veins terminate as the

deep (subdermal), middle, or superficial plexus

plexus that provides the major blood supply to the skin and is therefore of most importance with regards to cutaneous surgery

deep (subdermal) plexus

should you close bite wounds acutely

no

treatment of contaminated wounds (e.g. bite wound) prior to closure may include

lavage

abx

frequent bandage changes

topicals (e.g. silver)

negative pressure

areas of the body with extensive loose skin available for mobilization?

trunk

upper extremities

cervical region

areas of the body with limited skin available for mobilization?

eyes

ears

anogenital region

lower extremities

guide on how skin defects should be reconstructed/closed that result from gravitational and muscular forces

tension lines

if possible, incisions aare planned and made ? to tension lines to allow cosmetic closure with minimal tension

parallel

what instruments are appropriate when manipulating skin?

skin hooks

fine stay sutures

towel clamps

general suture size for reconstructive/cosmetic surgery?

2-0 to 4-0

suture material used in buried closure patterns?

absorbable monofilament (e.g. monocryl, biosyn (glycoemr))

suture material used for external skin closure?

nonabsorbable monofilament (e.g. nylon, polypropylene, and staples)

cosmetic yet time consuming suture pattern used to obtain accurate apposition

simple interrupted

efficient suture pattern with some tension relieving properties used to obtain good apposition

cruciate

cosmetic suture pattern that is primarily appositional, provides some tension relief, may be less irritating to the patient, and can be time consuming at first

intradermal/subcuticular

tension relieving suture pattern that can be combined with stents if necessary and may compromise blood supply

horizontal mattress

tension relieving suture pattern that may cause some everting of skin edges

vertical mattress

three main functions of walking sutures?

advance and appose skin edges

decrease tension

close dead space

disadvantages of walking sutures?

possible disruption of blood supply

possible pockets for seroma and abscess formation

dimply appearance

techniques for local skin mobilization and tension relief?

Undermining

Relaxing incisions

Various Plasty incisions (V to Y)

Local (subdermal plexus) flaps

easiest flaps to perform that rely on the subdermal plexus

local (subdermal plexus) flaps

the length to width ratio for local (subdermal) flaps must be equal to or less than

1.5

examples of local (subdermal) flaps ?

single pedicle advancement flap

bipedicle advancement flap

rotation flap

what local (subdermal) advancement flap provides improved blood supply and greater tissue coverage?

bipedicle advancement flap

flap using a region with a named direct cutaneous artery and vein

axial pattern flap

Axial pattern flap examples?

Caudal superficial epigastric

Caudal auricular

Deep circumflex iliac

Thoracodorsal

Tibia "crus"

Lateral Genicular

advantages of the caudal superficial epigastric (CSE) axial pattern flap?

Immediate and robust blood supply

Infection resistanc

Durable

Cosmetic

Can close large wounds

disadvantages of the caudal superficial epigastric (CSE) axial pattern flap?

Can't reach distal extremities

Large donor site

Time consuming

what is the maximum number of caudal mammary glands that can be used for a caudal superficial epigastric (CSE) axial pattern flap in dogs?

4 glands

what is the maximum number of caudal mammary glands that can be used for a caudal superficial epigastric (CSE) axial pattern flap in cats?

3 glands

Principles of axial pattern flap reconstruction?

Make a definitive incision

Dissect beneath panniculus

Use landmarks and transillumination

Dissect distal to proximal

Bridging incisions

Position with towel clamps

Use multiple people/teams for suturing

axial pattern flaps to know for exam

Caudal superficial epigastric

Caudal auricular

Antitragus

what is structure A?

Tragus

what is structure B?

Anthelix

what is structure C?

Scapha

what is structure D?

structures of the external ear?

vertical canal

horizontal canal

cartilages

glands (e.g. seruminous)

hair

the middle ear is also known as the

tympanic cavity

structure of the middle ear that connects to the nasopharynx

eustachian tube

species with a middle ear that is divided into two compartments by a septum

cat

structures of the inner ear?

labyrinth

semicircular canals

pinna laceration tx options?

Manage as wound

Primary wound closure

Pinnectomy

when can pinna lacerations be treated with primary wound closure?

If adequate and healthy tissue is present

Injury occurred within 6 hours

Suture patterns to close skin of pinnae lacerations?

Simple interrupted

Ford interlocking

Suture patterns to close skin and cartilage of pinna laceration together?

Vertical mattress

Figure of eight

criteria for partial or complete pinnectomy?

malignant tumor

ulcerated tumor

painful tumor

a ? thickness partial pinnectomy is indicated for malignant tumors

full

painful hemorrhage within layers of the pinna causing the layers of cartilage to separate due to trauma or an autoimmune response

aural hematoma

aural hematoma tx?

Address underlying cause

Treat quickly

Continuous drainage

Steroids/PRP possibly

TF needle aspiration of aural hematoma is an effective treatment

F

Methods for continuous drainage of aural hematoma?

teat cannula

penrose drain

closed suction drain

S shaped incision

circular fenestration

goals of aural hematoma tx?

remove clot

remove fibrin

close dead space

provide cosmesis and function

prevent recurrence

Indications for external ear surgery?

Stenosis

Poor/no response to medical management

Ear masses

Dystrophic mineralization

Trauma

TF most external ear surgeries are salvage procedures

T

Best diagnostic imaging method for evaluation of ear canal, extent of disease, and secondary changes from otitis externa/media?

CT

three most common surgical procedures employed for otitis externa?

Lateral wall resection

Vertical canal ablation

Total ear canal ablation and lateral bulla ostectomy (TECALBO)

rarely indicated procedure through which the lateral wall of the vertical canal is opened

lateral wall resection

indications for lateral wall resection?

Small tumor of lateral wall

Mild otitis externa affecting vertical canal

Congenital stenosis

rarely indicated procedure through which the vertical canal is removed and an opening is created for the horizontal canal

vertical canal ablation

vertical canal ablation indications?

Small tumor of vertical canal

Mild otitis externa affecting vertical canal

Congenital stenosis

TF lateral wall resection and vertical canal ablations are useful and effective procedures to treat otitis

F

commonly fails if treating otitis and becomes stenotic

procedure defined by complete removal of the vertical and horizontal canal as well as the lateral wall of the bulla that requires special equipment

total ear canal ablation and lateral bulla ostectomy (TECALBO)

indications for TECALBO?

severe chronic otitis

neoplasia

Steps of TECALBO?

Make incision around ear canal opening

Incision along vertical canal and make a flap for erect ears

Elevate auricular muscles from canal

Elevate canal from opening of bulla

Remove lateral wall of bulla

Remove epithelial lining from bulla cavity

Lavage

Culture and submit for histopath

Complications of TECALBO?

Facial nerve injury (temporary vs. permanent)

Deep infection (draining tract/abscess)

Hemorrhage

Damage to inner ear

Pinna necrosis

Airway swelling

Incisional complications

Loss of hearing

more common and temporary facial nerve injury that results from stretching of the nerve after ear surgery - resolves in 6-8 weeks

neuropraxia

failure to ? in a TECALBO can and often will result in infection/abscesses and draining tract formation within weeks to a year of surgery

remove all of the canal cartilage and epithelial lining of bulla

TF facial nerve injury is a very serious and life-threatening complication following ear surgery

F

mainly cosmetic, need to lubricate eyes with artificial tears to prevent corneal ulcers

important vessels to avoid when performing ear surgery?

retroarticular vein

external carotid

performing a bilateral TECABO raises the risk of what complication?

airway swelling

TF inner ear clinical signs that appear AFTER ear surgery are typically permanent

F

typically resolve in time

TECABO post op care?

Pain management

Abx and change based on culture

Incision care

benign pedunculated growth of fibrovascular tissue that arise due to congenital predisposition or chronic inflammation

inflammatory polyp

inflammatory polpys may arise from three locations?

Lining of auditory (eustachian tube)

Nasopharynx

Middle Ear

What are the consequences of polyps arising from the middle and/or inner ear?

Mass effect of infection

Horner's syndrome

Vestibular signs

Bony infection

what is the most common signalment for inflammatory polyps?

Cats

Average 2yo

Hx of URI

Hx of OE

external ear inflammatory polyp clinical signs?

Chronic OE that is unresponsive to topicals

Head shaking

Otorrhea

Visible or palpable painful mass

nasopharyngeal inflammatory polyp clinical signs?

Nasal d/c

Stertor

Sneezing

Dysphagia

Dyspnea

Megaesophagus

Middle ear inflammatory polyp clinical signs?

Head tilt

Horners

Ataxia

Nystagmus

Circling

Facial n. paralysis

Always do a ? if you suspect an inflammatory polyp to rule out other differentials

sedated otic exam

inflammatory polyp of nasal turbinates

hamartoma

TF facial palsy is a typical clinical sign of an inflammatory polyp in the middle ear

F

most likely neoplasia/large tumor

inflammatory polyp diagnostics?

PE

Radiographs to assess bulla and nasopharynx

CT

MRI if neurologic

Otoscopy

Anesthesized oral/nasopharyngeal exam

external ear inflammatory polyp tx?

traction avulsion

steps for external ear polyp traction avulsion?

Place patient under GA

Place hemostats, allis tissue forceps or alligators across stalk

Apply constant traction and rotate

Control hemorrhage with gentle pressure for 2-5 minutes

Clean residual debris from ear

unique steps for nasopharynx polyp traction avulsion?

Place patient under GA

Ensure adequate ET tube cuff inflation

Retract soft palate rostrally with spay hook or stay sutures

Pack laryngeal region/suction afterwards to control hemorrhage

What are your options for an inflammatory polyp after traction avulsion?

Medical management

Surgery (e.g. myringotomy, VBO, TECALBO)

when is medical management indicated for a polyp after traction avulsion ?

Clean bulla on imaging

No imaging will be performed

No signs of middle ear disease

what does medical management of a polyp consist of?

Prednisolone 1mg/kg 4-6 week taper

Veraflox for 2 weeks

Topical ear medication for 2 weeks

when is surgical management indicated for a polyp after traction avulsion ?

Recurrent polyp

Clinical signs of middle ear disease

Middle ear disease detected on imaging