Dog and Cat 2 Flashcards
Skin infections causes what are the most common and more occasional agents
- Staphylococcus pseudintermedius (common) - all over the dogs skin most concentrated around mouth and nose
- Malassezia pachydermatitis (common) - over the skin
○ OPPORTUNISTIC - MRSP (increasing big problem)
- Other Staphylococcal spp or yeast (occasional)
- Pseudomonas (occasional)
List 4 reasons dogs have a higher prevalence of skin infections
- Higher skin pH
- Less epidermal lipids -> atopic dogs have even less
- No follicular lipid plug -> prevents topical chemicals getting into hair follicle
- Atopic dermatitis is common in dogs -> 10% of population
List 6 reasons dogs get skin infections
- Anatomical reasons - skin folds (increased environment for infection) - brachycephalic dogs
- Microclimate changes - swimming especially with thick coat dogs - not drying thoroughly
- Decreased exfoliation/follicular obstruction - long term corticosteroid therapy (stop turnover of skin cells (exfoliation))
- Decreased Immunity
- Self-trauma (scratching) - break the skin and liberate proteins that the agents can use
- Atopic dermatitis
What are the 3 main types of skin infections and
- Surface
○ Malassezia are almost always SURFACE infection
○ Skin fold pyoderma, hot spots, otitis - classic - Superficial - MRSP common
- Deep - usually painful not itchy
Surface infections what is the main clinical presentation and common areas
Common presentation - No papules, pustules or cellulitis - Hyperpigmentation - Can be greasy or scaly/dry depending on the dog - Hot spots -> rapid development, aggressive, intensely pruritic Common areas - Skin folds - Most areas - humidity - Thickened skin
What breed is important in terms of surface skin infections and what occurs
Westies - Breed variation ○ Something in the skin that reacts with the bacteria ○ Non-specific inflammation ○ Hyperproliferative skin - Clinical importance ○ Difficult to control colonisation ○ Cytostatic therapy?
For surface infections what diagnostic techniques used, treatment and maintenance/prevention
Cytology 1. Tape preps 2. Roll preps 3. Direct impression Treatment Surface infections do better with surface treatment (topical treatment) - topical anti-bacterial/fungal Maintenance/prevention - Surgery (anatomical problems) - Control environmental wetting - Treat underlying disease (eg atopy) - Shampoos ○ Pyohex conditioner ○ Malaseb (miconazole, chlorhexidine) ○ Mediderm (piroctone olamine)
superficial infections what are the 2 main causes and how to diagnose the different presentations
Causes - Folliculitis ○ Demodicosis ○ Dermaophytosis - Pustules ○ Pemphigus foliaceous ○ Contact allergy - lesions look like pustules BUT NOT PUSS Diagnosis - Pustules ○ direct smear - Papules ○ direct smears ○ blunt scrape - Crusts ○ direct smear - Annular scale (dry lesions) ○ tape cytology
In terms of treating bacterial superficial infections what is an important drug and how long administer and why
- Cephalexin 22mg/kg bid (Rilexine) - PRIMARY CHOICE AS WORKS FOR MRSP
Treat for at least 7 days AFTER clinical resolution MINIMUM of 3 weeks - Watch out for MRSP
MRSP - Methicillin Resistant Staphylococcus pseudintermedius how transmitted, why an issue and risk factors
- Cultured from veterinary clinics -> carrier dogs will shed in this environment, susceptible animals then pick this up, not an issue until selected for via antimicrobials
○ Issue when gets into clinic and - Generally staph sensitive to beta-lactam antibiotics
○ Resistant -> low affinity penicillin binding protein - beta-lactams don’t work
○ Resistant genes can be transferred and have areas in DNA where other resistant genes can insert
§ Generally multi-drug resistant - Risk factors - going into veterinary clinics (waiting room), giving beta-lactam antibiotics with corticosteroids/apequal, going to dog groomers, antibiotic ear drops (absorb some into bloodstream)
Deep skin infections how generally present, how occur, causes and treatment
- Usually painful not itchy
- Is an extension from superficial infection after follicular rupture
- Often mechanical reasons
○ Over bony points
○ Weight bearing interdigital areas
Treatment
○ 6-8 weeks antibiotics
○ Anaerobic PLUS staph activity
○ Deep culture
○ Choosing antibiotic
§ Must be able to reach infection
§ Clindamycin good empirical choice
□ Get into cells (neutrophils/macrophage with bacteria within)
□ Good for Anaerobic bacteria
□ Can miss MRSP
§ NO STEROIDS!!
§ Re-assess each 2 weeks
§ Beware foreign bodies
What are some causes of repeat and recurrent infection
repeat - environmental riggers, anatomical reasons, foreign bodies, underlying disease recurrent infection - Atopy - Demodicosis - Other hypersensitivity diseases - Endocrinopathies - Keratinisation defects
Dermatophytosis - ringworm what are the 3 main types, animal within, does it fluroesces and zoonoses
Microsporum canis (cat) - Kittens, long haired cats (Persians) - Hair fluoresces - ZOONOTIC Trichophyton metagrophytes (rodents, GPs) - Dogs that hunt, rural exposure - Doesn't fluoresces - Not zoonotic Microsporum gypseum (soil) - Dogs that dig (face and forelegs)
3 ways to diagnose dermatophytosis and treatment
Diagnosis
- Wood’s lamp -> fluorescents so good for Microsporum
- Culture - good for Microsporum canis and trichophyton NOT MICROSPORUM GYPSEUM
- Biopsy - good for Microsporum gypseum
Treatment
- anti-fungal
- treat for 14 days past negative culture - ZOONOSIS
Give 5 indications for ovariohysterectomy
- Elective -Desexing/Population control
- Reduction of mammary neoplasia risk
- Treatment of behavioral conditions
- Treatment of other medical conditions
- Council registration
What is standard practice for desexing females, what occurs in shelters and claims for this
- Standard practice to desex females at age of about 6 months - before first or second oestrus
- More recently shelters 8-12 weeks -> debatable
○ Claimed decreased stress and operative time.
○ Assurance that the animal is desexed when it is re-homed.
○ Anaesthetic risk?
○ Decreased maturation of external genitalia
○ Increased incidence of oestrogen responsive urinary incontinence.
○ Increased risk of bony neoplasia in giant breeds?
What is an important difference with desexing female in season and what important if have a litter
○ Uterus more friable and increased blood supply - need to be confident with ligatures and haemostasis
○ Oestrogen can have a detrimental effect on haemostatic mechanisms.
○ If possible delay for 4 weeks after the onset of pro-oestrus.
§ Desexing an early pregnant bitch is easier than in season.○ After a litter, wait until 3 weeks after weaning to allow mammary tissue to involute.
How does the risk of mammary neoplasia change based on when spay
- Reduction in risk is a major benefit of canine OHE/OVE: (Lifetime risk of Mammary Neoplasia)
○ 0.5% if spayed cf intact before first oestrous -
○ 8% if spayed cf intact after the first oestrous
○ 26% if spayed cf intact after the second oestrous
○ No decrease in risk if spayed after 4 oestrous cycles
Entire cats have 7x the incidence of mammary tumours cf spayed queens
What are the 3 main ligaments of the female reproductive system and what connect
1) The broad ligaments consist of the mesovarium, mesosalpinx and the mesometrium.
2) The suspensory ligament is the cranial continuation of the broad ligament from the ovary –coalesces into a distinct band which inserts on the middle and ventral thirds of the last two ribs.
3) The proper ligament attaches the ovary to the uterine body - between ovary and uterine horn
Blood supply of the female reproductive tract what are the 2 main arteries and connections
1) Ovarian artery is a direct branch off the aorta.
§ The ovarian artery supplies the ovary and cranial aspect of the uterus
○ The right ovarian vein drains into the caudal vena cava.
○ The left ovarian vein drains into the left renal vein
2) Uterine artery
○ Branch of the internal pudendal artery
○ Positioned on the lateral aspect of the uterine body bilaterally
○ Enters the mesometrium at the level of the cervix
Anastomoses between the ovarian and uterine arteries are believed to exist
what are the lymphatics and innervation of the female reproductive tract
Lymphatics - Drain to the hypogastric and lumbar lymph nodes Innervation - Hypogastric plexus - sympathetic Pelvic nerves - parasympathetic
what is an important difference with canine and feline ovaries in terms of neutering
- Canine ovaries are difficult to expose (if on heat easier) and the cervix is easily mobilised
- Feline ovaries are easily exposed and the cervix is less mobile
ventral midline vs flank for neutering which better and why
- Ventral midline is MY preference over flank:
○ Better access to peritoneal cavity if problems occur
○ Can check haemostasis
○ Access to right ovary can be difficult through flank approach
○ Anecdotally increased incidence of seroma with flank procedures ( 3 x muscle layers)
○ BUT Flank approaches commonly performed in UK and at some welfare centresand private practices - Flank -> can be done depending on the clinic, generally done if have mastitis
what are the 7 main steps in ovariohesterectomy up to clamping ovary
1) express bladder
2) Canine - at or 1-2cm caudal to the umbilicus extending 5cm -> more cranial if younger due to suspensory ligament
- Feline - 3-4cm incision centred over the midpoint between the cranial rim of the pelvis and the umbilicus
3. Finding uterine horns
○ lies ventral to the rectum and dorsal to the bladder
4. Spay hook - introduce hook parallel to the body wall and rotate 90 degrees and move toward the midline
5. Exteriorise ovary –right is more difficult.
○ Stretch, break or cut suspensory ligament
6. Ligate the ovarian pedicle –create a window in the mesovariumcaudal to the ovarian vessels and triple clamp with Carmault-Rochester forceps.
7. 3 clamps proximal to ovary if possible otherwise one clamp between the ovary and uterus
Steps 8 - 13 in ovariohesterectomy starting after 3 clamp method
- Tie into the crush
- Selection of suture size depends on the amount of fat in the pedicle and your confidence in your ligature.
○ Dog 0 –2/0, cat 2/0 –3/0
○ Consider slipknot or Miller’s knot - Transect the ovarian pedicle and hold the pedicle in forceps without tension before releasing into the peritoneal cavity.
- The broad ligament may be cut or broken down with fingers.
- Avoid the uterine vessels.
- In multiparous, pregnant or mature dogs there may be large branching vessels that require ligation. - Check abdominal cavity for haemorrhage - normal to have some bleeding
- Linea alba closure –interrupted or continuous monofilament absorbable (1 –3/0) egpolydioxanone. Ensure closure incorporating rectus sheath.
○ Best NOT to use chromic catgut in a continuous manner
What are 5 important complications of ovariohysterectomy
1) haemorrhage - most common (70%)
2) wound healing complications - sutuer reaction, seroma
3) ovarian remnant syndrome - NEED TO REMOVE ENTIRE OVARY
4) urinary incontinence - 11-20%
5) weight gain - 26-38%
Ovariectomy V Ovariohysterectomy
- Historical preference in Australia, the UK and the US for ovariohysterectomy in the bitch and the queen
- Due to concerns regarding uterine disease post-operatively when exogenous hormonal therapy has been administered for:
- no significant differences between techniques were discovered for incidence of:
○ endometritis/pyometra
○ urinary incontinence
○ obesity.
What is the most importnat pre-op consideration with casearian and desex or not
- Time from anaesthetic induction to delivery of pups should be as short as possible - therefore as much prep needs to be done before induction
- Anaesthesia–maximise dam safety / minimise foetal depression.
Desex or not? Controversy.
○ May prolong anaesthesia/SxVS save a subsequent procedure. Loss of circulating volume?
○ Take longer to recover -> need to stay in longer at the clinic BUT want the mum and pups to go home and start nursing as soon as possible
○ If won’t return to desex then should do it
What are the 10 main steps in a casearaian
- Ventral midline approach, 2 –3cm cranial to and 5 –6 cm caudal to the umbilicus.
○ Take care not to damage the abdominal contents particularly the gravid uterus. - Pack off the uterus from the abdominal cavity with laparotomy sponges
- Incise the uterus in an avascular area within the body that will allow removal of foetuses from both horns.
○ Sometimes multiple incisions will be required. - Gently milk each foetus to the uterine incision
- Break through foetal membranes and clamp the umbilicus 2-3cm from its base
- Rub foetuses vigorously to stimulate breathing
○ Give supplemental warmth and O2 - CHECK ALL FOETUSES ARE REMOVED
○ Especially check the uterine body and vagina - A Cushing or Lembertpattern is recommended with synthetic absorbable monofilament suture.
- The uterus is thoroughly lavaged before being returned to the abdomen.
- Change gloves and instruments and close the abdomen
What are the 3 main complications of casaearians
- Haemorrhage–intrauterine (oxytocinor ovariohysterectomy) or peritoneal (ligature failure)
- Infection –especially if long procedure or gross contamination of peritoneal cavity.
- Foetal or maternal death.
Vaginal oedema/hyperplasia when occur, what occurs, how present, what breed more suscepible and treatment
- During oestrogenic phase (oestrus and proestrous)
- Vaginal mucosa becomes swollen allowing a transverse fold to prolapsethrough the vulva
- Presents as a large mass protruding through the vulva
- Exposed tissue predisposed to dessication, ulceration and trauma
- Esp. Brachycephalic breeds
- Regresses spontaneously during the luteal phase but interferes with breeding and may recur during parturition resulting in dystocia.
Treatment - OVH provides permanent relief.
- Other treatments include:
1. excision of the prolapse (haemorrhage) - not common
2. conservative (lubrication, sugar water to help reduce oedemaand manually try to reduce followed by purse string suture)
3. pharmacologic induction of ovulation (GnRH or hCG)
Vaginal prolapse how common, breed predisposed, how differeniate with hyperplasia, what occurs and treat
- Rare
- Brachycephalic breeds predisposed
- Differentiated from hyperplasia by circumferential prolapseof the vagina. Must also be differentiated from tumour–careful examination +/-biopsy
- Occurs after forced separation during mating or in the advanced stages of parturition due to excessive straining.
- If recognised early an attempt can be made to reduce the prolapsehowever amputation is often necessary.
Neoplasia of vulva/vagina benign or malignant most commonly, what type generally and treatment
- 70 –80% benign
- Most common leiomyoma, fibromaor lipoma.
- Malignant: leiomyosarcoma
- Surgical excision is treatment of choice.
what are the 3 main issue with entire males
○ Population control ○ Unwanted behaviour: § Aggression § Marking § Mounting ○ Disease: § Testicular Neoplasia § Prostatic disease (Prostatitis, BPH, Prostatic cysts) § Perineal hernia § Perianal adenoma
List 6 main reasons for castration
- Population control:
- Prevention of behavioural issues
- Prevention / Treatment of testicular tumours
- Prevention / Treatment of prostatic disease:
○ Benign Prostatic Hypertrophy/Prostatitis/Cysts
○ Exception of prostatic neoplasia (androgen independent in most dogs) - Primary/adjunctive therapy of perianal adenoma
- Treatment of Testicular torsion
Timing for castration what is optimal age and why
- Traditionally believed 6-9 months as optimal age:
○ Avoids perceived problems of anaesthesia in young animals
○ Performed prior to development of sexual maturity:
○ Population control
○ Undesirable male behaviour
○ Evidence?
What are the 2 main surgical castration techniques and which is preferred
- Open Castration
- Preferred method:
○ All structures can be visualised
○ Ligatures applied directly to vessels without interposed tunics. - closed castration
what is the difference between open and cloased castration
- Initial technique similar to open BUT
○ Tunica albuginea NOT incised
○ Testicle and cord separated from surrounding soft tissue attachment
○ DOUBLE (slippery tunic) ligature technique:
§ Proximal ligature into crush
§ Distal transfixation ligature - Closure and incision identical identical:
○ Avoid suturing the urethra!!
○ Prescrotal incision
○ 2 layer closure –incorporate raphe
feline castration how occurs and what is scrotal ablation and what used in
FELINE - 2 scrotal incisions and testicular exposure (gentle pressure), scrotal incision heal via second intention healing - just leave to drain Scrotal Ablation - Cutting around the scrotum - Indicated in: ○ Mature dogs with pendulous scrotum ○ Cosmetic ○ Dogs with scrotal/testicular neoplasia ○ Dogs with scrotal/testicular infectious dz
List 5 complications associated with castration and 2 ways to prevent
○ Scrotal bruising / haematoma - proper ligation of vessels ○ Haemorrhage ○ Dermatitis ○ Infection / Abscess ○ Persistent Priapism in cats Prevention: ○ Good surgical technique ○ Prevention of self-trauma -> loose sutures
