SA soft tissue surgery Flashcards
what are halsteds principles of surgery?
gentle tissue handling meticulous haemostasis preservation of blood supply strict asepsis minimal tension accurate tissue apposition obliteration of dead space
why is meticulous haemostasis important in surgery?
haemorrhage can obscure the surgical field and provide a medium for bacterial growth
can cause hypovolaemia, shock or death if not controlled
why is it important to not leave dead space in a cavity after surgery?
blood or tissue fluid can accumulate and form a haematoma or serum which provides a medium for bacterial growth increasing the chance of infection
what should always be used to attach a blade to a scalpel handle?
needed holders (avoid cutting yourself)
what are the ways of holding a scalpel?
pencil grip
fingertip grip
palm grip
what is the pencil grip on the scalpel used for?
short precise incisions due to small contact area
what is the fingertip grip on the scalpel used for?
for inactions over 3cm long (maximised blade/tissue contact)
when is the palm grip on a scalpel used?
rarely (allows substantial force but very imprecise)
what types of cutting can be done with a scalpel?
press cutting
slide cutting
how is press cutting done with a scalpel?
using the pencil grip and applying gradually increasing pressure in the direction of the motion of the blade (stab incision)
how is slide cutting done with a scalpel?
using any grip apply pressure at a right angle to the direction of motion of the blade while the other hand tenses the tissue laterally
why should slide cutting be done in a single motion?
creates less trauma and ensures smooth wound edges with less haemorrhage
what types of tissues are scissors very useful for cutting?
flaccid tissue that can’t be cut efficiently with a scalpel
what are metzenbaum scissors used for?
fine dissection
what are mayo scissors used for?
dissecting connective tissue/fascia
what are curved and straight scissors used for?
curved - dense tissue
straight - fine dissection
what forces are responsible for cutting when using scissors?
closing force - pushing blades together
shearing force - sliding blades over eachother
torque force - rolling leading edge of blade in to touch the other
what is the backhand thumb-third finger grip used for?
scissor cutting towards the dominant hand
what is the backhand thumb-index finger grip used for?
cutting across the table toward your body
what part of the scissors should be used for cutting?
tip (not the hinge)
what are the three ways of cutting with scissors?
scissor cutting
push cutting
blunt dissection
what is blunt dissection using scissors?
insert closed blades into tissue and open them then withdraw back
what are electrosurgical instruments used for?
coagulating or incising tissue
what are the types of electrosurgical instruments?
monopolar
unipolar
describe a monopolar electrosurgical instrument
electrode in the handpick and a ground plate
what can monopolar electrosurgical instruments be used for?
cutting
coagulation
what are bipolar electrosurgical instruments used for?
coagulation
haemostasis
why shouldn’t electrosurgery be used in excess?
causes more trauma to the surrounding tissues than using a scalpel or scissors
what should be remembered when using electrosurgery?
anaesthetised patients only
don’t use in presence of volatile gases/liquids
ground plate should be in complete contact with the animal
don’t wrap lead around towel clips (may induce burns)
keep electrode clean for proper function
keep power as low as possible
what are toothed forceps used for?
gripping tissue with minimal pressure (less traumatic)
what are two types of toothed forceps?
adson
debakey
describe the debakey forcep
fine atraumatic jaw pattern to the teeth
what should non-toothed forceps be used for?
handling inanimate objects (dressings…)
what are the types of tissue forceps?
allis
babcock
doyen
what are allis and babcock tissue forceps used for?
tissue that is going to be excised (they are traumatic)
what are doyen forceps used for?
holding and occluding the lumen of bowel (gap between the jaw avoids crushing tissue)
what are the types of retractors?
finger-held retractors
hand-held retractors
self-restraining retractors (balfour, gossett retractors, finochietto rib retractors, gulp retractors)
what are finger held retractors used for?
retraction of thin/delicate tissue
what are hand-held retractors used for?
retraction of thicker/robust tissue
what are balfour retractors used for?
abdominal wall retraction (used to lift the diploid process)
what are gossett retractors used for?
abdominal wall retraction
what are finochietto rib retractors used for?
separate ribs for intercostal thoracotomy
divide halves if sternum for median sternotomy
why is wound irrigation/lavage important?
avoid drying and trauma to tissue
role in asepsis
what are the types of suction tip?
frazier-ferguson
yankauer
poole
what is the frazier-ferguson suction tip good for?
removing haemorrhage during fine dissection
what is the yankauer suction tip good for?
removing large volumes of fluid fro body cavities
what is the advantage of the poole suction tip?
doesn’t block easily (multiple suction holes)
what are some complications of improper tissue handling?
tissue ischaemia - delayed healing/necrosis dead space formation wound contamination increased post-op pain poorer cosmetic results
what is tensile strength of a suture material proportional to?
diameter of the suture
what should the tensile strength of a suture material be the same as?
strength of the tissue
what are the ideal properties of a suture material?
easy to handle
low tissue drag
resistant to contamination
good knot security
what are the two categories of suture material structure?
monofilament
multifilament
what are the advantages of monofilament suture material?
little tissue drag
withstand contamination well
what are the disadvantages of monofilament suture material?
prone to damage by instruments
high degree of memory - harder to handle and poor knot security
what are the advantages of multifilament suture material?
less memory - easy to handle and high knot security
higher surface friction - better knot security
what are the disadvantages of multifilament suture material?
can harbour bacteria (act as a wick)
increased tissue drag (reduced by coating)
what two ways can suture material be divided by chemical composition?
absorbable vs non-absorbable
synthetic vs natural
what are non-absorbable sutures mainly used for?
skin
hernia, ligament and tendon repair
how are absorbable synthetic sutures broken down? what does this cause?
hydrolysis - minimal tissue reaction
how are absorbable natural sutures broken down? what does this cause?
enzymatic reactions - inflammation and tissue reaction
what suture material should be used in contaminated/infected wounds?
smallest amount possible of synthetic monofilament suture material
what tissues can absorbable sutures be used on?
visceral wounds (heal quicker)
name a natural absorbable suture material
catgut
is catgut monofilament or multifilament?
multifilament
name some synthetic absorbable suture material
dexon vicryl polysorb monocryl biosyn PDS
which synthetic absorbable suture material is monofilament?
monocryl
biosyn
PDS
which synthetic absorbable suture materials multifilament?
dexon
vicryl
polysorb
name some synthetic non-absorbable suture material
nylon
supramid
prolene (surgilene)
what are the two methods suture material is attached to a needle?
swaged-on
eyed needle
what are the advantages of swaged-on needles?
less traumatic to tissue as you get a new sharp needle each time
easier to use
what is the advantages of eyed needles?
they are cheap and reusable
what are the two shapes of needles?
straight
curved
what are straight needles used for?
suturing near body surface or the skin
what are curved needles used for?
(most sutures)
narrow wounds deep in body cavities
what are the two types of point profiles of needles?
round bodied
cutting needles
what are round bodied needles used for suturing?
easily penetrated tissue such as fat, viscera or muscle
what are the three types of cutting needle?
conventional cutting needle
reverse cutting needle
taper-cut needles
describe conventional cutting needles
cutting edge on concave surface (can cause suture material to cut towards the edge of the incision)
describe reverse cutting needles
cutting edge on convex surface (less likely for suture to cut towards the incision)
what is the difference between mayo-hear and olsen-hegar needle holders?
Olsen-hegar have scissors built into them
what are the three effects sutures can have on tissue alignment?
appositional
inverting
everting
what does an appositional suture do?
brings wound edges into direct contact (most widely used)
what to inverting sutures do?
turn the suture edges inwards
what do everting sutures do?
turn the suture edges outwards
what are the types of interrupted suture pattern?
simple
cruciate mattress
vertical mattress
horizontal mattress
what are the advantages of simple interrupted suture patterns?
minimal interference with blood supply
allows tension to be easily adjusted across the wound
accurate apposition
what are the advantages of the cruciate mattress suture pattern?
tension relieving
doesn’t interfere with wound healing
what is the cruciate mattress pattern used for?
skin closure
what is the main advantage of the vertical mattress suture pattern?
doesn’t interfere with blood supply around the wound edge
what are the disadvantages of the horizontal mattress pattern?
can cause skin eversion
poor stability to wound edges
interfere with blood supply
what are some continuous suture patterns?
simple continuous
continuous horizontal mattress
ford interlocking
what is the disadvantage of continuous suture patterns?
breakage will cause the whole suture to fail
what are the advantages of the simple continuous pattern?
good tissue apposition
spreads tension evenly across the wound
what are the advantages of intradermal sutures?
no sutures to remove
no sutures passing through the skin surface to cause irritation or infection
minimal scar formation
what are subcutaneous sutures used for?
decrease tension across wound before placing skin sutures
reduce dead space
what type of pattern is used for subcutaneous tissue sutures?
simple continuous
continuous horizontal mattress
what suture patterns are used for the skin?
simple interrupted
cruciate mattress
continuous intradermal
what wounds are staples not suitable for?
wounds under tension
wound with irregular edges
less than 6mm depth of tissue separating them from bone/viscera
what is the name of tissue adhesives?
cyanoacrylate
what wounds are tissue adhesives used on?
small skin wounds under low tension
what wounds are tissue adhesives not suitable for?
mucous membranes (don't adhere well on moist surfaces) larger wounds under tension
define -tomy
to incise into
define -ectomy
to remove
define -centesis
introduction of a needle into a cavity to aspirate fluid/gas
define -pexy
surgical fixation of an organ/structure
define -rraphy
act of suturing
define -stomy
surgically creating an opening
define -desis
secure fixation by surgical methods
define -plasty
surgical shaping/moulding of a structure
what are the phases of wound healing?
lag/inflammatory
repair
remodelling
how long does the lag phase of wound healing last?
1-5 days
what is the immediate response to injury that initiates the lag phase?
haemostasis
what happens during haemostasis?
cells/fluid exit blood vessels and platelets trigger the formation of fibrin clots to form the provisional extracellular matrix and stabilise the wounds edges
during the lag phase what are the first cells attracted to the wound?
neutrophils
what are neutrophils attracted to the wound by?
chemotaxis
what is the role of neutrophils in the lag phase of wound healing?
degrade necrotic tissue and control infection by destroying bacteria
what cells enter the wound after the neutrophils?
monocytes
what do monocytes differentiate into once they have entered the wound?
macrophages
what is the role of macrophages in the wound?
remove degenerate neutrophils, necrotic tissue and debris by phagocytosis
how long does the repair phase of wound healing last?
6-16 days
what are the three overlapping parts of the repair phase of wound healing?
connective tissue repair
wound contraction
epithelialisation
what do mesenchymal cells differentiate into during connective tissue repair?
fibroblasts
what do the fibroblasts create during connective tissue repair?
new collagenous extracellular matrix
what allows fibroblast migration into the wound?
angiogenesis (capillary ingrowth)
what happens towards the end of the connective tissue repair stage of wound healing?
fibroblasts and new capillaries undergo apoptosis resulting in granulation tissue becoming acellular (paler scarring)
in full thickness skin wounds, how long does it take for wound contraction to start?
5-9 days
what causes wound contraction?
specialised myofibroblasts proliferate in the wound, attach to the wound matrix and each other then begin to contract
when does epithelialisation begin in partial thickness skin wounds?
immediately
when does epithelialisation begin in full thickness skin wounds?
4-5 days post injury
what is required in full thickness skin wounds before epithelialisation can occur?
a granulation tissue bed
describe the process of epithelialisation of wounds
epithelial cells from wound edges migrate across the wound to form a monolayer, they then begin to proliferate to increase the epithelial thickness
they become firmly attached to the dermis and over time stratifies
what can be mistaken for infection during suture wound healing?
epithelial proliferation causing an inflammatory response a keratinising epithelial cells contact connective tissue
when does the remodelling stage of wound healing begin?
14-16 days post injury
what happens during the remodelling phase of wound healing?
cellular content of the granulation tissue reduces and collagen bundles reorganise by thickening, cross linking and reorientation along tension lines
what local factors can effect wound healing?
wound perfusion tissue viability wound fluid accumulation infection mechanical factors
why is wound perfusion so important to healing?
dividing cells require a lot of oxygen to be able to divide
what is the rate limiting step of wound perfusion?
new capillary formation in the granulation tissue bed
what effect does tissue viability have on wound healing?
devitalised/necrotic tissue and debris will prolong the inflammatory phase and delay healing
how does fluid accumulation in wounds slow healing?
physically separates the tissue and puts pressure on surrounding tissue which reduces perfusion
what effect does bacterial infection have on wound healing?
prolongs inflammatory phase
reduces chemotaxis
increases tissue damage
reduces fibroblast activity and collagen synthesis (decreases wound strength)
what are some systemic factors that can effect wound healing?
immunosuppression
neoplasia
why does neoplasia effect wound healing?
cancer cachexia due to increased cytokine level
cytotoxic drugs/radiotherapy can kill rapidly dividing cells
what is the specific response of the intestine to a wound?
collagenase activity decreases the wound strength
what is crucial to successful intestinal wound healing?
avoiding infection
preservation of blood supply
avoiding tension
how does skeletal muscle heal from small wounds?
regeneration with minimal fibrous tissue formation (if held in close apposition)
what are the specific responses to a wound to a peripheral nerve?
severed ends retract
cell body swells
nucleus becomes eccentrically placed
axon undergoes Wallerian degeneration
what is significant about wound healing of the liver?
regenerate up to 80% of its volume in 6 weeks by proliferation and hypertrophy
what are the two ways in which wounds can be classified?
degree of contamination
aetiology
what are the degrees of wound contamination?
clean
clean contaminated
contaminated
dirty
describe a clean wound
elective surgical wounds not entering respiratory, urogenital or GI tracts with no break in asepsis and primary closure
describe a clean contaminated wound
surgical wounds involving respiratory, urogenital or GI tract without significant contamination or minor breaks in asepsis
describe a contaminated wound
fresh traumatic would less than 6 hours old
surgical wounds involving respiratory, urogenital or GI tract with significant contamination
surgery in presence of inflammation
major breaks in asepsis
describe a dirty wound
traumatic wound greater than 6 hours old
traumatic wounds contaminated with foreign material/significantly devitalised tissue present
surgery in presence of abscessation
what are the categories of etiologically classifying a wound?
abrasion avulsion degloving incision laceration puncture burn
what is an abrasion?
partial thickness wound with loss of epidermis and part of dermis
what is an avulsion?
tearing of tissue from its attachments
what is a devolving injury?
low-velocity avulsion of skin due to rotational force
what is an incision wound?
sharp trauma resulting in smooth edged wound
what is a laceration?
sharp trauma resulting in irregular wound with tearing of tissue
what is a puncture wound?
penetration by a sharp object
why must care be taken with puncture wounds?
often minimal superficial damage but infection and damage to deeper structure (especially abdomen/thorax)
what is the first stage on preparing a wound for closure?
take a swab for bacteriology
how should a wound be prepared for treatment?
cover with sterile ointment (KY jelly) or sterile swabs then clip the edges working away from the wound
surgically scrub around d the wound (do not allow detergents to come into contact with the wound)
what are the ways a wound can be debrided?
hydrodynamic
hydromechanical
surgical
what is hydrodynamic debridement also known as?
lavage
what are the aims of lavage?
decrease bacteria in wound
remove debris
prevent further contamination
how should grossly contained wounds be lavaged?
tap water
what is used to lavage a wound?
large volume of isotonic solution
what can be added to the final lavage?
antiseptics
what antiseptic can be used at the end of lavage?
chlorhexidine
povidone iodine
what is used for hydromechanical debridement?
amorphous hydrogel dressings
what functions do amorphous hydrogel dressings have?
promote hydration and autolysis of necrotic tissue absorb sloughing tissue moisten the wound prevent eschar formation allow cell migration/proliferation bacteriostatic
what do amorphous hydrogel dressings contain to make them bacteriostatic?
propylene glycol
when should amorphous hydrogel dressings be removed?
when dressing is changed (by lavage)
what should hydrogel be covered with when in wounds containing necrotic tissue?
non-adherent semi-occlusive primary layer (fenestrated polyester film)
what should wounds with lots of exudate be covered with?
hydrocellular foam dressing - won’t absorb gel but will wick away excess moisture
how should tissue viability be evaluated when deciding on surgical debridement?
tissue colour, pulse and bleeding
if in doubt about whether to surgically decried a wound, what should be done?
manage as an open wound until obvious demarcation of devitalised tissue occurs
what are the types of wound closure?
primary
delayed primary
secondary
secondary intention healing
what is primary closure of a wound?
immediate suture closure without tension
what is delayed primary closure of a wound?
closure of wound 1-5 days after injury before granulation bed forms
what is secondary closure of a wound?
closure of a wound 5 days after injury once the granulation bed has formed
what must be done just before closing a wound by secondary closure?
excise around wound edge or granulation tissue margin then close
what are the layers of dressing?
primary (contact)
secondary (intermediate)
tertiary (outer)
what are the two types of primary dressing layer?
adherent
non-adherent
why do adherent dressing layers adhere to the wound?
fibrinous material, granulation tissue or exudate penetrates their structure and dries
why are adherent primary dressing layer not commonly used?
slow healing
painful to remove
can cause tissue maceration
what factors determine which type of non-adherent dressing to use?
what you want the dressing to do
how much exudate is being produced
if the wound is infected
what dressing should be used to deride necrotic tissue?
non-adherent with hydrogel
what dressing should be used used for a wound in the repair phase of healing?
non-adherent dressing for protection (to speed up granulation tissue formation)
what are the most absorbent/permeable non-adherent dressings?
calcium aginate
polyurethane foam dressings
fenestrated polyester film
what is the least absorbent/permeable non-adherent dressing type?
polyethylene film dressing
how often does the dressing of infected wounds need to be changed?
at least once a day
what are the type of non-adherent dressings?
calcium aginate fenestrated polyester film hydrocellular foam hydrocolloid polyethylene petrolatum-impregnated gauze hyperosmolar agents maggots silver dressing
what is calcium aginate dressing indicated for?
full/partial thickness wounds at any stage of healing with moderate/heavy exudation
what are fenestrated polyester film dressings mainly used for?
protecting wounds with an intact epithelial surface
what type of lesions are hydrocellular foam dressing good for?
ulcers
what does silver dressing do?
release bacteriocidal silver ions into the wound
what do maggots do?
debridement (difficult to keep them in the right place) - useful as antibacterial resistance increases
what is an example of a hyperosmolar agent that can be used in dressings?
honey
what are the actions of honey when used as a hyperosmolar dressing?
dehydrate bacteria to impair growth
low pH reduces bacterial growth
what is the function of the secondary layer of a dressing?
draws away and absorbs excess fluid keep primary layer in contact with wound obliterate dead space protect wound (padding) support and immobilisation
what are some types of secondary layers of dressings?
cast paddings
disposable nappies
cotton wool
what is the function of the tertiary layer of dressing?
support
keep other layers clean
what are the haemostat techniques?
pressure haemostatic forceps electrosurgery ligatures vascular clips topical haemostat agents
what types of haemorrhage should pressure be used to control?
low-pressure haemorrhage
temporarily to high-pressure haemorrhage to allow time to select a better technique
how should pressure be applied to haemorrhage?
for 5 minutes with a saline moistened swab (take care when removing not to remove clot)
what vessels should haemostatic forceps be used on?
ones that are going to be sacrificed rather than repaired
what are the methods of clamping using haemostatic forceps?
tip clamping
jaw clamping
what is tip clamping? and what is it used for?
apply tip of smaller haemostat to tissue to occlude small vessels
describe the features of monopolar cautery
current flows from single hand electrode to a ground plate under the patient
what are the types of electrosurgery?
radiofrequency instruments
vessel sealing devices
what are the two radio frequency devices used for haemostasis?
monpolar cautery
bipolar cautery
what are the advantages of bipolar cautery?
more precise
requires less current
works better in a wet field
what are the two types of vessel sealing devices?
elecrtrothermal bipolar vessel sealers
harmonic scalpels
how do harmonic scalpels work?
ultrasonic vibrations of the instruments tip cause heating and coagulation of tissue
what are the two types of ligatures used for haemostasis?
simple/circumferential
transfixing
describe a circumferential ligature
simple loop placed a few mm from the end of the cut vessel
how should large vessels (arteries) be ligated?
circumferential and a distal transfixing ligature
what is a transfixing ligature?
penetrates the vessel and then encircles it in a figure of eight pattern
what are the advantages of vascular clips?
rapid and convenient (but more expensive than ligatures)
what are examples of topical haemostatic agents?
granules, powder or sheets of collagen or fibrin
how do topical haemostatic agents work?
act as a scaffold for fibrin clot formation
what are used for?
persistent capillary haemorrhage
what are risk factors for increased wound infection?
type/number of bacteria clipping surgical site anaesthesia/surgical time propofol use endocrinopathies number of people in operating room sex of patient local wound environment
how does the clipping of a surgical site effect the risk of wound infection?
causes microtrauma to the skin the can increase bacterial growth
when should skin be clipped relative to surgery?
immediately before to avoid bacterial growth due to microtrauma
why does increased anaesthetic time and surgical time increase the risk of wound infection?
immunosuppression
increased tissue handling
longer exposure of bacteria
why can propofol use increase the risk of wound infection?
it is suspended in lipid that can support bacterial growth (if contaminated and injected it can cause infection)
why do endocrinopathies increase the risk of wound infection?
many of them can cause immunosuppression
what sex are more at risk of wound infection?
males
why are male patients more at risk of wound infection?
due to the immunomodulatory effects of androgens
what can impair tissue response to an infection?
trauma foreign material ischaemia poor nutrition chemotherapy systemic disease
what ways can surgical infections be prevented?
patient selection/prep surgical team prep sterilisation of equipment operating theatre prep wound lavage post-op care antibacterial
what patients should elective surgery be postponed in?
those with pre-existing disease/infections
what should be used on a regular basis in autoclave machines to ensure the sterilisation is efficient?
biological indicators
should prophylactic antibacterials be used for clean surgeries?
only if they last longer than 90 minutes or if the animal is at risk due to other factors
should prophylactic antibacterials be used for clean contaminated surgeries?
yes
should prophylactic antibacterials be used for dirty surgeries?
no the wound is already infected, use therapeutic antibacterials
define antisepsis
use of germicidal substances on living tissue
define disinfection
use of germicidal substances on inanimate objects
define nosocomial infections
hospita; enquired infections often caused by highly antibacterial resistant strains of bacteria
define sterilisation
process of destroying all micro-organisms
define a surgical infection
infection developing at the site of a surgery within 30 days of the surgery (1 year if its an implant)
what are the main clinical signs of nasal disease?
sneezing increased respiratory noise nasal discharge epistaxis facial pain
what are the common causes of acute nasal disease?
nasal foreign body
viral URT infection
allergic/irritant rhinitis
tooth root abscess
what are the two usual clinical signs of acute nasal disease?
snoring
serous nasal discharge
what are the common causes of chronic nasal disease?
progression of acute disease
feline rhinotracheitis
fungal rhinitis (aspergillosis)
lymphocytic/plasmacytic rhinitis
what would be examined on a clinical exam of a patient with suspected nasal disease?
symmetry of the head
nasal discharge, crusting, ulceration, depigmentation
pain and swellings
retropulse both globes
assess airflow (place hair by nares)
oral cavity - dental disease, fistulae, palate defects
palpate submandibular lymph node
what are some possible diagnostic tests that can be carried out to diagnose nasal disease?
blood tests virology radiography/imaging rhinos copy nasal biopsy forced flush FNA swabs
what blood tests can be carried out for suspected nasal disease?
haematology/biochemistry
clotting profile
serology
why may clotting profiles be carried out for suspected nasal disease?
if epistaxis is the only clinical sign
what species is virology used for in suspected nasal disease?
cats
what are the most useful radiographs for detecting nasal disease?
lateral of the skull
dorsoventral intramural of nasal cavity
rostrocaudal of frontal sinuses
if nasal neoplasia is suspected, what diagnostic test should be carried out?
thoracic radiography to look for metastasis
what should be done if haemorrhage after a nasal biopsy doesn’t stop after a few minutes?
flush nasal cavity with ice cold saline and place ice pack on the maxilla to cause vasoconstriction
where in the nasal cavity should not be biopsied blind?
caudal to medial canthus of the eye
why should you not blind biopsy caudal to medial canthus of the eye?
because you may damage he cribriform plate
how is a forced nasal flush carried out?
cuffed endotracheal tube is placed and abdominal swabs packed into the common pharynx
the nasal cavities are then flushed under pressure to dislodge any foreign bodies or tissue fragments which will then be collected in the pharyngeal swabs
what can you do an FNA of to help diagnose nasal disease?
mandibular or retropharyngeal lymph nodes (if enlarged or firm)
what is fungal rhinosinusitis usually due to in dogs?
Aspergillus fumigatus
what is fungal rhinosinusitis usually due to in cats?
Cryptococcus neoformans (rare)
what dogs most commonly get fungal rhinosinusitis?
young/middle aged medium/large breed dogs
what can fungal rhinitis cause extensive damage to?
turbinates
what are the clinical signs of fungal rhinitis?
nasal discharge epistaxis facial pain ulceration/depigemented nares dullness/depression
what type of nasal discharge is associated with final rhinitis?
mucopurulent
how can be used to diagnose fungal rhinitis?
history/clinical signs serology radiography rhinoscopy histopathology
what is seen on radiographs of animals with fungal rhinitis?
turbinate bone destruction
increased fluid density in the cavity
what will rhinoscopy of dogs with fungal rhinitis reveal?
fungal plaques
turbinate destruction
what is the gold standard of diagnosing fungal rhinitis?
histopathology
what can be used to treat fungal rhinitis?
topical antifungals
how are topical fungals used to treat fungal rhinitis?
trephination of frontal sinus and flush with sterile saline followed by packing of the sinus and nasal cavity with clotrimazole cream
soaking of nasal cavity with cltrimazole solutions using foley catheters
are tumours of the nasal cavity usually benign or malignant?
malignant
what neoplasias can effect the nasal cavity?
adenocarcinoma osteosarcoma chondrosarcoma squamous cell carcinoma fibrosarcoma lymphoma
what are the clinical signs of nasal neoplasia?
reduced airflow nasal discharge (with epistaxis) facial swelling/distortion palate swelling/distortion exophthalmos neurological signs
when may neurological signs be a clinical sign of nasal neoplasia?
if it extends through the cribriform plate
when may exophthalmos be a clinical sign of nasal neoplasia?
if there is invasion of the retrobulbar space
what can be used to diagnose nasal neoplasia?
history/clinical signs
diagnostic imaging
rhinoscopy (biopsy)
when taking a biopsy of a nasal mass, what must you be careful of?
not taking too smaller sample - will only contain normal nasal mucosa overlying neoplasia
what can be done to treat nasal lymphomas?
chemotherapy
what is the most effective treatment of nasal neoplasms?
radiation therapy (not usually curative)
what palliative treatments can be used for nasal neoplasias?
antibacterials
analgesics
anti-inflammatories
what is non-infectious inflammatory rhinitis also known as?
lymphocytic/plasmacytic rhinitis
what are the clinical signs of non-infectious inflammatory rhinitis?
bilateral serous/mucopurulent nasal discharge
sneezing
snorting
what can be used to diagnose non-infectious inflammatory rhinitis?
history/clinical signs
diagnostic imaging
rhinoscopy and biopsy
what will be the findings on diagnostic imaging of animals with non-infectious inflammatory rhinitis?
mild loss of turbinate detail
increased soft tissue density (due to discharge)
how can biopsy help to diagnose non-infectious inflammatory rhinitis?
histopathology to view lymphocytic/plasmocytic infiltration of the mucosa with possible secondary bacterial infection and neutrophilic inflammation
how effective is treatment of non-infectious inflammatory rhinitis?
rarely curative and will often require longterm treatment
what are the options for treating non-infectious inflammatory rhinitis?
environmental modification saline in nares to liquefy/clear discharge nasal flushes NSAIDs antibacterials mucolytics test/eliminate allergens
what effect does doxycycline have on the nares?
anti-inflammatory on nasal mucosa
antibacterial
how can the environment be modified to treat non-infectious inflammatory rhinitis?
minimise exposure to irritants/allergens through ventilation, cleaning and humidification
what are the clinical signs of nasal foreign bodies?
sudden onset
sneezing
distress/face pawing
purulent nasal discharge (unilateral)
what can be used to diagnose nasal foreign bodies?
history/clinical signs
rhinoscopy
diagnostic imaging
exploratory rhinotomy (last resort)
how are nasal foreign bodies treated?
nasal flushing
endoscopic removal
rostral retraction of the soft palate and retrieval
rhinotomy (last resort)
what are some less common causes of nasal discharge?
dental disease bacterial rhinitis cleft palate ciliary dyskinesis parasites (rare) dysphagia causing nasopharyngeal reflux
what is a major risk of rhinotomy?
haemorrhage - apply tourniquet around common carotid artery (whole blood should be available for transfusion)
what has caused brachycephalic obstructive syndrome (BOS)?
selective breeding leading to shortening of the skull but without the same reduction of volume of connective tissue
what are the primary components of BOS?
overlong soft palate
stenotic nares
tracheal /laryngeal hypoplasia
what secondary change can occur as BOS progresses?
tonsillar enlargement and protrusion
laryngeal collapse
tracheal collapse
describe the laryngeal collapse associated with BOS
eversion of the laryngeal saccules and progressive medial deviation of the corniculate and cuneiform processes of the arytenoid cartilage
what are the clinical signs of brachycephalic obstructive syndrome?
marked inspiratory noise dyspnoea snoring sleep apnoea exercise intolerance cyanosis fainting/collapse gagging dysphagia regurgitation coughing
is starter or stridor associated with brachycephalic obstructive syndrome?
stertor
what can exacerbate the clinical signs of BOS?
heat, excitement, exercise
what can be used to diagnose BOS?
breed, history, clinical signs
examination of upper airway
radiography
what is assessed in BOS cases by examination of the airway under light anaesthesia?
tonsillar size/protrusion from the crypts
soft palate - should just overlap the epiglottis
larynx - look for collapse
why does care need to be taken when assessing the soft palate length of BOS patients?
don’t pull the tongue forward as this will displace the larynx/epiglottis and cause an overestimation of palate length
what is assessed on radiographs of suspected BOS patients?
pharyngeal airway
tracheal diameter
signs of aspiration pneumonia
other causes of upper airway obstruction (masses…)
what are the options for treatment of brachycephalic obstructive syndrome?
rhinoplasty
palatoplasty
laryngeal sacculectomy
tonsillectomy
when should you intervene surgically with BOS cases?
if indicated by severity of clinical signs and impact on quality of life
as soon as possible before there is extensive secondary changes
wait until animal is skeletally mature so the tissue is less delicate and there is more room
what should be done to stabilise severe BOS cases?
cool, quiet environment supplementary oxygen sedation IV corticosteroids intubate to bypass obstruction
describe the rhinoplasty performed on BOS cases
lateral, vertical or horizontal wedge resection of the dorso-lateral nasal cartilages
how is haemorrhage controlled when performing rhinoplasty in BOS cases?
2 absorbable sutures placed in the defects
what is given to patients undergoing palatoplasty? and why?
IV corticosteroid to reduce post-op airway swelling
describe the procedure of a palatoplasty for BOS patients
resect the excess soft palate to it just overlaps the epiglottis
what is the limit for resection of the soft palate?
caudal border of tonsillar crypts
why should you not resect further than the caudal border of the tonsillar crypts?
will allow nasopharyngeal reflux of food/fluid leading to a chronic rhinitis
describe the process of laryngeal sacculectomy for BOS patients
grasp the everted laryngeal saccule mucosa and amputate level with the laryngeal mucosa
what usually causes laryngeal collapse?
secondary to chronic upper airway obstruction leading to increase resistance and hence increase negative pressure and turbulence
what are the stages of laryngeal collapse?
1 - eversion of laryngeal saccules
2 - eversion of laryngeal saccules and medial deviation of the cuneiform process of the arytenoids
3 - eversion of laryngeal saccules and medial deviation of the cuneiform and corniculate processes of the arytenoid cartilages
how is stage 1 laryngeal collapse treated?
laryngeal sacculectomy
how are stage 2/3 laryngeal collapse treated?
laryngeal sacculectomy with/without arytenoid caudolateralisation
what is an alternative treatment for laryngeal collapse if laryngeal sacculectomy fails?
permanent tracheostomy
describe the procedure of arytenoid caudolateralisation for patients with laryngeal collapse
arytenoid cartilage is pulled further caudal than normal so it is medially supported by the cricoid cartilage preventing the medial deviation
what can cause laryngeal paralysis?
congenital dysfunction of the recurrent laryngeal nerve
idiopathic degeneration of the recurrent laryngeal nerve
neuropathy due to metabolic disease
myopathies
trauma/neoplasia effecting the recurrent laryngeal nerve
what can paralysis of the dorsal cricoarytenoid result in?
reduced size of the glottis and increased airway resistance during inspiration
what breeds are predisposed to acquired laryngeal paralysis?
golden retrievers
labradors
irish setters
what breeds are predisposed to congenital laryngeal paralysis?
Bouvier des Flandres
white German shepherds
what are the clinical signs of laryngeal paralysis?
inspiratory stridor exercise intolerance fainting/collapse altered phonation coughing/gagging during swallowing dysphagia
what can be used to diagnose laryngeal paralysis?
history/clinical signs laryngoscopy thoracic/cervical radiographs haematology/biochemistry electromyography
what is being observed during a laryngoscopy off patients with suspected laryngeal collapse?
arytenoid cartilages should abduct during inspiration and adduct during expiration - take care with paradoxical movements caused by turbulence
what is cervical/thoracic radiography used for when examining for suspected laryngeal disease?
mass lesions and concurrent aspiration pneumonia
what is haematology/biochemistry used for in cases of suspected laryngeal paralysis?
to rule out metabolic disease
what is the most common treatment of laryngeal paralysis?
arytenoid lateralisation (laryngeal tieback)
describe the procedure of arytenoid lateralisation (tie back)
sutures permanently placed to permanently abduct the arytenoid cartilage and open the glottis
usually unilaterally on the left
why is arytenoid lateralisation done unilaterally on the left side?
surgery on the left is easier for right handed surgeon
unilateral provided adequate airway for most cases but also minimises postoperative aspiration pneumonia
what are some possible complications associated with arytenoid lateralisation (tie back)?
aspiration pneumonia
suture/cartilage breakage
serum development
what techniques can be used to investigate tracheal disease?
clinical exam diagnostic imagery tracheobronchoscopy biopsy tracheal wash
how can tracheal disease be investigated on a clinical examination?
auscultation of larynx, cervical trachea and thorax to localise respiratory noise
palpation of cervical trachea - changes in shape (collapse, neoplasia..)
why are many tracheal abnormalities visible on radiographs?
high contrast between air filled lumen and surrounding soft tissues
what diagnostic imagining can be used to visualise dynamic tracheal abnormalities?
fluoroscopy
what are tracheal washes and bronchioaveolar lavage useful for?
bacterial culture
cytology
what can cause tracheal tears?
sharp penetrating objects
blunt trauma
overinflation of cuffed ET tube in cats
what can large tears of the trachea cause?
subcutaneous emphysema
pneumothorax
what can be done to treat tracheal tears?
cage rest if not dyspneic
tracheoscopy - expose, decried and suture
where does tracheal avulsion usually occur?
in the intrathoracic trachea caudal to the bifurcation
how can tracheal avulsion be diagnosed?
history of trauma and progressive dyspnoea
tracheoscopy
toracic radiography
what will tracheoscopy reveal in patients with tracheal avulsion?
circumferential tracheal ring disruption or tracheal stenosis
what will thoracic radiography reveal in patients with tracheal avulsion?
intrathoracic pseudo trachea (area of gas density in line with the trachea)
how is tracheal avulsion treated?
decried and anastomose avulsed ends
what causes tracheal collapse?
laxity of the tracheal muscle
chondromalacia of the tracheal rings
how is the severity of tracheal collapse catagorised?
grade I-IV
describe a grade I tracheal collapse
laxity of the dorsal tracheal membrane resulting in 25% collapse of the lumen
describe a grade II tracheal collapse
loss of cartilage rigidity and further laxity of the membrane resulting in 50% collapse of the lumen
describe a grade III tracheal collapse
flattening of the tracheal cartilage resulting in 75% collapse of the lumen
describe a grade IV tracheal collapse
collapse of the rings resulting in 100% loss of luminal integrity
tracheal collapse is a dynamic process, describe this
cervical trachea collapses on inspiration and the intrathoracic trachea collapses on expiration
what animals is tracheal collapse usually seen in?
small/toy dog breeds
what are the clinical signs of tracheal collapse?
cough (goose honk) - elicited by tracheal pressure
waxing/waning dyspnoea
exercise intolerance
cyanosis
flattening of cervical trachea on palpation
what can be used to diagnose tracheal collapse?
signalment, clinical signs, history
endoscopy
fluoroscopy
radiography
what can fluoroscopy be used for when diagnosing tracheal collapse?
can reveal changes in the lumen diameter during inspiration/expiration
how is tracheoscopy used when diagnosing tracheal collapse?
determine the location and grade of the collapse
what can be done in most cases to treat tracheal collapse?
medical management - most dogs respond for more than 12 months
what medical management techniques can be used in the treatment of tracheal collapse?
weight loss (if required) avoid stress, heat, excitement... use harness instead of collar address any other airway disease corticosteroids antitussives bronchodilators antibacterials for concurrent infections
what are possible surgical treatments of tracheal collapse?
intraluminal stent
extraluminal stent
what are some complications of intraluminal stenting to treat tracheal collapse?
stent migration
stent fracture
failure to integrate into mucosa
what will failure of an intraluminal stent to integrate into the tracheal mucosa result in?
reduced mucociliary clearance
granulation tissue formation
tracheal stenosis
collapse of unstented trachea/bronchi
what is used for extraluminal stenting of the trachea?
prosthetic rings
what are some complications of extraluminal stenting for treating tracheal collapse?
iatrogenic damage to laryngeal nerves
tracheal necrosis (disrupted blood flow)
persistent cough
further collapse
what is done to reduce the complication of laryngeal collapse due to damaged nerves caused by extraluminal stenting?
concurrent arytenoid lateralisation
what animals is tracheal hypoplasia most commonly seen in?
tracheal hypoplasia
how is tracheal hypoplasia diagnosed?
lateral cervical/thoracic radiographs
how is tracheal hypoplasia treated?
management of other airway abnormalities (stenotic nares, long soft palate…)
symptomatic treatment to improve mucociliary clearance
what is tracheal necrosis?
abnormal narrowing due to trauma and excessive granulation tissue formation
what are the clinical signs of tracheal stenosis?
progressive cough
exercise intolerance
dyspnoea
what can be used to diagnose tracheal stenosis?
history/clinical signs
diagnostic imaging
tracheoscopy and biopsy
what can be done to treat tracheal stenosis?
tracheal resection and anastomosis
what can be done to treat tracheal neoplasia?
excision and anastomosis for small minimally invasive neoplasms
chemotherapy
radiotherapy for lymphoma
how is the cervical trachea accessed for surgery?
ventral midline incision, separating the sternohyoideus muscles along the midline to reveal the trachea
how is the thoracic trachea accessed for surgery?
3rd to 5th intercostal space thoracotomy on the level of the lesion
what type of blood supply does the trachea have?
segmental
why does care need to be taken with tracheal surgery?
close to many important structures - recurrent laryngeal, carotid arteries, thyroid gland
what should be used to close tracheal injuries?
monofilament absorbable suture material with knots placed extraluminally
what is temporary tracheostomy used for?
release potentially life threatening URT obstruction
assist ventilation
removal of secretion or aspirated materials
inhalation anaesthetic agents
describe the technique for placing a temporary tracheostomy tube
incise skin and separate right/left sternothyroid and sternohyoid
make a transverse incision between the 4th/5th tracheal rings
place a suture loop cranial and caudal to the incision
place a non-cuffed tracheostomy tube into the lumen
suture skin around the tube leaving an open wound for replacing the tube
place a light bandage
how does a tracheostomy tube have to be maintained?
change at least twice a week
clean/disinfect
suction airway when required
moisten airway every 1-4 hours
what are some common complications associated with tracheostomy tubes?
tube obstruction/removal gagging/coughing SC emphysema pneumothorax infection tracheal stenosis
what should be done before removing a tracheostomy tube?
occlude the tube for 15-20 minutes to ensure no respiratory distress
how is the stoma of tracheostomy tube placement allowed to heal?
secondary intention
how are permanent tracheostomy tubes managed?
cleaning opening keep hair short maintain good BCS cover when outside restrict patient from swimming
what is tracheal resection indicated for?
congenital or acquired tracheal strictures
localised tracheal neoplasia
tracheal granuloma
what is the maximum number of tracheal rings you can remove?
5-6
what are some developmental abnormalities of the kidneys?
renal agenesis
renal dysplasia
renal ectopia
polycystic kidney disease
what species are predisposed to polycystic kidney disease?
Persians
Bull terriers
what is renal agenesis?
when the kidney and ureter aren’t present
what is renal dysplasia?
disorganisation of the parenchyma
what are the indications for a renal biopsy?
renal mass (most common) haematuria of UUT origin renal cortical disease renal failure of unknown cause evaluate severity of renal disease
what tests should be carried out before a renal biopsy?
haematology serum biochemistry urinalysis diagnostic imaging coagulation profile
what are the contraindications for a renal biopsy?
anaemia coagulopathy oliguria/anuria/severe azotaemia hypertension urinary obstruction hydronephrosis renal abscess solitary functioning kidney
what are some potential complications of renal biopsies?
haemarrhage haematuria hydronephrosis renal infarction damage to renal vasculature infection fibrosis
what are the methods of taking a renal biopsy?
FNA
tru-cut needle
surgical
what does tru-cut or FNA take a renal sample of??
the cortex (don't go in medulla - causes problems)
why are FNA and tru-cut renal biopsies taken under ultrasound guidance?
to make sure you don’t put the needle in the medulla
what are the ways of approaching the kidney for a biopsy?
ultrasound guided
keyhole (flank)
laparoscopic
ventral midline coeliotomy
how do you expose the right kidney when doing a midline coeliotomy?
retract descending duodenum to the midline
how do you expose the left kidney when doing a midline coeliotomy?
retract the colon to the midline
which kidney has multiple arteries?
left
what is a nephrotomy?
an incision into the kidney
what are the indications for a nephrotomy?
wedge biopsy
removal of nephroliths
how should haemostasis be carried out during a nephrotomy?
using assistants fingers or vascular clamps for no longer than 20 minutes
what is bisectional removal of calculi from the kidney?
incisioin made from pole to pole of the kidney
after removing the nephroliths from the kidney, what must you do?
check for patency of the ureter
what must be done at the end of a nephrotomy?
fix the kidney back onto the body wall
what are the two types of neophrotomy to remove calculi?
bisectional
intersegmental
what are the clinical signs of nephroliths?
lumbar/abdominal pain
haematuria
recurrent UTI
azotaemia
how can nephroliths be treated?
medical management - specific diets
surgery
what type of nephroliths don’t respond to medical management?
calcium oxalate
what is ureteronephrectomy?
removal of the kidney and associated ureter
what are the indications for ureteronephrectomy?
trauma
hydronephrosis
renal masses
harvest for transplant
what is a key aspect that must be taken into account before carrying out a ureteronephrectomy?
animals must have two functioning kidneys
what is the only indication for partial nephrectomy?
if patient has lost other kidney and need to do surgery on the other kidney
what is the most common renal neoplasm in cats?
lymphoma
what is the most common neoplasm in dogs?
renal cell carcinoma
are primary or metastatic renal neoplasms more common?
metastatic
what are the clinical signs of renal neoplasia?
(slow onset) haematuria weight loss depression/lethargy inappetance pyrexia lameness abdominal distension
how are renal neoplasms investigated?
abdominal palpation haematology/biochemistry radiography computed tomography ultrasound biopsy (check for metastasis)
is renal lymphoma in cats usually bilateral or unilateral?
bilateral
how can renal neoplasms be treated?
lymphoma - chemotherapy
ureteronephrectomy
why is surgery to remove renal neoplasms often challenging?
can be metastasis and extensive neovascularisation (high risk of haemorrhage)
what are some possible congenital abnormalities of the bladder?
patent urachus
vesicourachal diverticulum
what does the urachus connect?
bladder and allantoic sac
what s vesicourachal diverticulum?
when the external opening of the rachis closes but the blind ending diverticulum remains open
where on the bladder should be avoided during surgery?
trigone
what is cystotomy?
opening of the bladder
what are the indications for cystotomy?
removal of calculi repair bladder trauma biopsy/resection of bladder mass biopsy of bladder wall repair ectopic ureters
what is the surgical approach for cystotomy?
ventral midline coeliotomy from umbilicus to the pubis
isolate the bladder and place stay sutures
make incision and suction urine
why is gentle tissue manipulation of the bladder very important?
the urothelium quickly becomes congested and oedematous
what suture material is used to close the bladder?
monofilament - monocryl
what two patterns of suture can be used to close the bladder?
single layer of simple interrupted/continuous
double layer using inverting continuous pattern
how fast does the bladder heal?
rapidly - 100% strength in 2-3 weeks
what is the postoperative management after cystotomy?
hospitalisation to monitor urination
don’t palpate abdomen
what are possible complications associated with cystotomy?
haematuria
dysuria
uroabdomen (uncommon)
what are the main types of bladder calculi?
struvite
calcium oxalate
what are the clinical signs of bladder calculi?
haematuria
pollakuria
stranguria
dysuria
how are baldder calculi diagnosed?
radiography pneumocystography double contrast cystography ultrasound CT
what are the possible causes of bladder rupture?
trauma
neoplasia
urethral obstruction
iatrogenic
what are the clinical signs of bladder rupture?
haematuria, dysuria
abdominal bruising
abdominal distention
depression, vomiting, shock
how can bladder rupture be diagnosed?
history/clinical exam abscence of urine on catheterisation urethral obstruction azotaemia, dehydration, metabolic acidosis abdominocentesis ultrasound positive contrast study
what differences will be seen in the fluid from abdominocentesis of patients with bladder rupture?
increased creatinine and potassium (higher than serum)
how is bladder rupture treated?
fluid therapy and urine drainage
closure of rupture (same as cystotomy) after exploratory laparotomy to identify the defect
what does cystostomy tubes allow?
urinary diversion and avoid bladder distention
what are the indications for a cystostomy tube?
bladder or urethral surgery
obstructed bladder neck or urethral neoplasia
neurogenic bladder atony
what is the most common bladder neoplasia of dogs/cats?
transitional cell carcinoma
how can bladder neoplasias be treated?
chemotherapy NSAIDs cystostomy tubes urethral stenting partial cystectomy
what is the difference between male and female urethras?
female - shorter and wider
males - divided into pelvic, membranous and penile urethra
what are the possible clinical signs of patients with urinary tract disease?
haematuria polyuria/polydipsia dysuria pollakiuria stranguria oliguria anuria nocturia incontinence lethargy collapse pyrexia weight loss vomiting/diarrhoea abdominal/lumbar pain
what is dysuria?
pain on urination
what is polydipsia defined by?
water intake exceeding 100ml/kg/day
what is polyuria define by?
urine output higher than 50ml/kg/day
what is oliguria?
lower than normal urine output
what is pollackiuria?
frequent small amounts of urination
what vital parameters are assessed in patients with urinary tract disease?
HR, RR, hydration, MM colour, mentation, temperature
what is assessed on abdominal palpation in patients with urinary tract disease?
pain
changes in kidney size
