Dog and Cat 1 Flashcards
what type of breeders are dogs, when puberty and interoestrus interval
- Non-seasonal breeders
- Spontaneous ovulation
- Puberty at time of first oestrous cycle
○ 3.5 to 24 months (breed dependent) - average 10-12 months
○ Generally small breeds experience their first oestrus earlier and large breeds later - Interoestrus interval (IEI)
○ Average: 7 months
○ Normal range: 5 to 12 months
○ Dormitory effect
Prooestrus of dogs average duration, what occurs in terms of hormones
- Average duration of 9 days
- This is when bleeding occurs -> not shedding internal lining but due to hyperaemia
- Maximum oestrogen levels - different from others
- Progesterone is starting to rise
Placental take over of production of progesterone what species never has this take over
Pigs, cats, dog
- Never placental take over for the production of progesterone
○ Some progestagens produced by the placenta but not complete take over
What are the 3 important series of events with dog breeding and what occurs/how you know when occur
Day 0 (d0) = day of the LH surge (most important)
- First day serum progesterone doubles/rises > 2ng/ml
Days 1-7 = -6 days of oestrus
- In relation to LH surge
D1 = first day of dioestrus
- Based on cytology (decrease of keratinised cells to <50%)
○ Also get neutrophils -> normal in dioestrus, anoestrus BUT NOT OESTRUS
§ Not in oestrus because of the keratinised epithelium of uterus
§ Once get dioestrus sloughing of keratinised epithelium and neutrophils leave
What are 4 important features of a pre-breeding exam
- Signalment, history
- General exam, esp. hereditary diseases
- Special reproduction exam
○ Digital palpation of vulva and vagina - in large breed dogs as can have strictures
○ Vaginoscopy
○ Cytology
○ Microbiology??? - waste of time and money - B. canis test - important in north america
oocyte maturation what days are important
- d0
- d2 -D3 ovulation
- d4 - D6 oocytes
- d6 - cervix closes
D1 = d8 = first day of dioestrus
Maximum fertility of occyte and insemination times for fresh, chilled and frozen semen
Maximum fertility
- From days 4-8 possible fertility
- All oocytes are fertile day 5-6 or day 5
Insemination times
- Fresh semen: 6 days -> inseminate on day 3 and 5 OR day 4 and 6
- Chilled semen: 2 days -> inseminate on day 3 and 5 OR day 4 and 6
- Frozen semen: 24h -> inseminate on day 4 or 5 OR 5 and 6, if only one dose: day 5
What are 4 important tests to determine when breeding is to occur
1) Breeding reflexes - starts in prooestrus and progresses through oestrus
2) Vaginal exam- speculum
3) Exfoliative cytology - prooestrus see non and cornified cells, 100% cornified is oestrous but not necessary LH surge
○ If have 100% cornification but also neutrophils -> INFECTION (endometritis) - not as common as horses
4) Serum progesterone levels - should do with cytology
In terms of breeding reflexes what are important things to look for
- “flagging”: lateral deviation of the tail
- “winking”: upward tipping of the vulva
- “lordosis”: standing firmly and arching her back
- Note vaginal discharge
○ Proestrus - bloody
○ Oestrus - less bloody
○ Dioestrus - puss
Vaginoscopy for breeding management what use and what do you see in different stages of oestrus
- Use (plexi) glass speculum and light source
- Note vaginal wall and folds
○ Pro-oestrus: pink, swollen, rounded folds, moist
○ Oestrus: pale-pink, shrunken/angular (crenulated), dry
○ Dioestrus: hyperaemic areas, rounded folds
Vaginal cytology what does it reflect, excellent to determine, good and not useful
- Reflects endogenous oestrogen levels
- Excellent to determine dioestrus (D1)
- Good to determine
○ Early prooestrus vs late prooestrus/oestus
○ Prooestus/oestrus vs dioestrus/anoestrus - Not useful to determine ovulation or ideal time of breeding
What are the 2 main types of cells in the reproductive tract and cells within
- Non-cornified cells
○ Parabasal cells: small, round - oval, “fried egg” appearance
○ Intermediate cells: larger than parabasal cells, higher cytoplasm: nuclear ratio - Cornified cells
○ Superficial cells: pyknotic nuclei, angular shape to the cytoplasm
○ Anuclear squamous cells: anuclear largest of vaginal epithelial cells, resemble cornflakes
In terms of vaginal cytology what is present in anoestrus
○ Non-cornified epithelial cells
§ Mainly small, round parabasal cells and intermediate cells
○ Neutrophils can be present
○ Bacteria can be present
In terms of vaginal cytology what is present in prooestrus
○ Shift from parabasal and intermediate cells to superficial cells
○ Numerous red blood cells
○ Neutrophils commonly observed
○ Bacteria commonly observed
In terms of vaginal cytology what is present in oestrus
○ >90% cornified cells marks beginning of “cytological oestrus”; superficial and anuclear squamous cells (Dead)
§ Oestrogen leads to hyperplasia or the wall
○ Bacteria can be present
○ BUT no neutrophils present (as above)
In terms of vaginal cytology what is present on dioestrus
○ 1st day with <50% keratinized epithelial cells marks D1
○ Increase in parabasal and intermediate cells
○ Many neutrophils observed - progesterone leading to sloughing of epithelial cells
○ Metoestral cells: neutrophils found in cytoplasm
○ Copious amount of vaginal discharge sometimes observed -> “dioestral dumping” of neutrophils
In terms of breeding management what are important practices
- Sampling every 2 to 3 days (M,W,F)
- Start in prooestrus
- Breeding reflexes, vaginoscopy and cytology should be done until D1
- Serum progesterone levels should be assessed q 2d until LH surge; blood should also be taken at time of breeding and on D1 (serum can be frozen in case of negative preg check)
Serum progesterone concentrations what concetrations occur at LH surge, time of ovulation, fertile period and after this range. what aiming for with breeding
- 2 ng/ml at time of LH surge (or doubling of previous level)
- 5 ng/ml at time of ovulation
- 10-25 ng/ml at time of fertile period (variable) - day 5-6
- VERY variable thereafter
- Aim for one breeding between 15-20 ng/ml
Vaginal semen deposition natural vs artifical insemination in terms of what day to breed and pros and cons
- Natural mating - day 5: allow natural mating
○ Pros: largest litter size (same as surgical and endoscope)
○ Cons: no semen assessment - Artifical insemination (AI) with catheter (eg. Flexible horse catheter) - day 3 collect semen, assess and then inseminate
○ Pros: easy to do
Cons: smaller litter size, not suitable for frozen semen
Intrauterine semen deposition what are the 2 types how to do and pros and cons
- Transcervical
○ Endoscope - most common but specialised
§ Pros: certain, good success rate
§ Cons: expensive equipment
○ Norwegian catheter
§ Pros: cheap
§ Cons: difficult to learn, risk of perforation - Surgical
○ Greyhounds with frozen semen have to have this
○ Pros: certain
○ Cons: surgical complications, ethical issues (highly invasive)
Where do you deposit the semen in bitch reproductive tract and how do you achieve for fresh and frozen semen
- Fresh semen: Location Vagina Technique catheter (can use endoscope as better outcome but more expensive)
- Frozen semen: Location Uterus Technique Transcervical endoscope
what is the best way to determine the first day of dioestrus and what results from oestrogenisation
What is the best way to determine the first day of dioestrus
- Vaginal cytology smear -> presence of neutrophils, clumping cornified and presence of increasing non-cornified
Oestrogenisation
- High levels of oestrogen results in cornification cells within the vagina
- Results in either tumor or ovarian remnant syndrome
What are 2 main reasons a desexed dog has discharge and how to differentiate
- Pyometra or vaginitis -> non-cornified cells found on vaginal smear
- Ovarian remnant syndrome - cornified cells found on vaginal smear
What are 4 main pregnancy diagnosis techniques, at what days post LH surge and how common AND what shouldn’t you use
1) Ultrasonography: > 20 days post LH surge
○ If don’t see anything may need to come back in a week as too early
2) Abdominal palpation: > 25 days post LH surge
○ Not necessarily pregnancy, may be pyometra
3) Relaxin test: > 28 days post LH surge
○ Not often, generally just use ultrasound
4) Radiography: > 44 days post LH surge
Beware: serum progesterone levels are NEVER to be used as an indicator of pregnancy in the bitch
What are the 2 main treatments for termination of pregnancy
1) #1 treatment: ovariohysterectomy! ○ Do you want to breed her in the future?? 2) In breeding bitch: confirm pregnancy at appropriate time - If pregnant: ○ PGF2alpha ○ Dopamine agonists ○ Aglepristone ○ Corticosteroids - Dexamethasone Or a combination of the above
What is important to remember when using Aglepristone (Alizin) and what main uses
1) Abortion
registered in Australia for induction of abortion in the bitch from 0 – 45 days after mating
○ Before about 45 days, foetus is resorbed
§ Should wait till off heat as if given then mate again 2-3 days later
○ After 45 days, they deliver the foetus -> not nice, want it to be done before this
○ 2 injections 24 hours apart
○ MUST be given by a vet
2) induction of parturition
- Off-label use of Alizin
- Evidence it’s safe from day 58-59
- Takes >24h
What are the 3 main ways to estimate whelping date
1) 57 +/- 1 day post D1 of dioestrus
2) 65 +/- day post LH surge
3) BUT: 65 +/- 8 days post breeding
§ If have breeding date -> Could be breed in prooestrus or last day of heat oestrus
□ If want to know when whelp more accurate -> ultrasound (on day 20) - gestational age
What are the 3 stages in whelping, how long does it take and what occurs
Stage I (6 to 12 hours; up to 24h)
- Nesting behaviour, off food, restlessness, vomiting, anorexia shivering —-> cervical dilation, vaginal relaxation, uterine contractions
Stage II (3 to 12 hours)
- Water breaks, Expulsion of first pup can last up to 4 hours, usually 30 min to 2 hours in between pups; may take break
○ Large issue if there are contractions without a puppy
Stage III (variable)
- Expulsion of allantochorionic foetal membranes
○ Occurs at the same time as stage II -> Randomally dispersed between pups
What are 6 signs of dystocia in bitches
- Whelping not observed after temperature drop
○ Progesterone taken away (thermogenic) will result in temperature drop
○ Should take temperature regularly for a few days prior to know when the drop is - Active labour > 4 hours and non pup produced
- Green-coloured or malodorous vaginal discharge in first stage labour
○ Detachment of the placenta -> normal in stage III - Interval between pups > 30 min (with myometrial contractions)
- Interval between pups >2 hours (without myometrial contractions)
- Signs of pain or diffuse vaginal bleeding
what occurs if it is an obstructive dystocia and what are the 2 things you should do
- EMERGENCY
- But take time to examine the bitch and reach a diagnosis
- Should still do two procedures
1. Vaginal exam - feel for puppy, and should contract if not - hypocalcaemia
2. Ultrasonography - foetal viability and heart rate
Elective caesarean section what do you need to know, signs and what should you do beforehand
- Important to know dO and D1
- Progesterone drops 24 to 48 hours praepartum
- Rectal temperature drops 8 to 24 hours
- Check foetal heart rates in last couple of days (especially in singleton pregnancy)
Uterine inertia how assess, treatment and what is important
- Assess hypocalcaemia clinically
- Blood Ca levels (even ionised) can be normal in clinically hypocalcaemia bitch
- Give 10%- Ca solution INTRAVENOUSLY
- ALWAYS listen to heart while administering calcium
○ Heart rate will slow, then increase so do again - Give calcium TO EFFECT
- Oxytocin may be helpful but often not necessary (no one has diagnosed hypooxytocinaemia)
List the 3 main postpartum diseases
1) Eclampsia
2) metritis
3) subinvolution of placental sites
Eclampsia when most common, clinical signs, treatment and prevention
○ Observed mainly in toy breeds with large litters (3 + puppies) < 28 days post partum
○ Clinical signs: tremors, nervousness, salivation; late stage: opisthotonus
○ Treatment: calcium IV to effect, oral calcium supplementation, wean puppies if >4 weeks
○ Prevention: adequate Ca:P ratio per partum
§ Recommend off the shelf pregnancy feed
Metritis when does it generally occur in dogs, clinical signs, diagnosis and treatment
○ Acute puerperal metritis occurs 0 to 7 days pp due to retained foetal membranes/fetuses, dystocia etc. and secondary infection
○ Clinical signs: fever, anorexia, vaginal discharge, doughy enlarged uterus
○ Diagnosis: cytology: neutrophils, bacteria (phagocytosed), membrane parts, WBC: leukogram can be normal initially
○ Treatment: treat shock, antibiotics (broad-spectrum), evacuate uterus
Subinvolution of placental sites what occurs, what age common, clinical signs and treatment
- Delayed involution of placental sites
○ More often in bitches <3 years of age
○ Clinical signs: sanguineous vaginal discharge > 6 weeks post-partum
○ Treatment: often self-limiting, OHE if necessary
False pregnancy what are the clinical signs, pathogenesis and treatment
- Clinical signs ○ Mammary development and galactorrhea ○ Nesting and "mothering" behaviour ○ Abdominal distention/uterine enlargement - Pathogenesis ○ Low Progesterone -> so spaying doesn't help ○ High Prolactin - Treatment Prolactin antagonist (Cabergoline)
Hypoluteinism what occurs and treatment
- Often diagnosed but never proven
- Progesterone supplementation in the dogs needs clear indication - not recommended
- Side effects are substantial -> risk of pyometra and uterine enlargement
Pyometra how common, and how occurs
- Affects 24% of intact bitches before 10 years of age
- Due to not being able to get rid of bacteria before the cervix closes
- 75-93% of affected bitches show clinical signs within 12 weeks of their last heat
1) E. coli is isolated from the uterus in up to 96% of clinical cases
2) Progesterone -> stays high even when not pregnant within dioestrus - Stimulates proliferation and secretion of endometrial glands (uterine milk)
- Keeps cervix functionally closed
- Inhibits myometrial contractions
Reduced immune response to pathogens
3) These effects are exacerbated if the uterus is previously primed with oestrogen - Therefore multiple oestrus cycles without pregnancy will have a “cumulative effect”
○ CEH (cystic endometrial hyperplasia) -> all with pyometra will have this, can be secondary
4) RESULT: the perfect environment for bacteria
In terms of pyometra what is the classic and atypical patient
The "classic" patient - Middle aged to old - Intact, in dioestrus - Has not been pregnancy - THERE ARE EXCEPTIONS The "atypical" patient - Breed predisposition: ○ Increased risk: goldern retriever, cavalier king Charles, miniature schnauzer ○ Lower risk: Pekingese, boxer, poodle, fox terrier, dachshund, German shepherd - Anecdotal familial clustering
What are the 2 types of pyometra and clinical signs
- Open pyometra - more obvious as discharge but generally not as systemically sick
- Closed pyometra - generally more systemically sick
Clinical signs
- Not definitive
- Pyometra should be suspected in any intact bitch presenting
○ 4 to 12 weeks after having been in heat
With vaginal discharge, depression, PU/PD, vomiting, and/or pyrexia
What are the 3 main ways to diagnose pyometra and 3 different differential diagnosis
- History
- Whole blood count (neutrophilia with left shift)
- Ultrasonography - always recommended
- Differential diagnosis
○ Mucometra
○ Hydrometra
Haemometra
What are the 4 main treatment options for pyometra
1) #1 treatment - OVARIOHYSTERECTOMY
2) If in breeding animal -> evacuate the uterus
○ Low dose prostaglandinF2alpha - low dosage in the beginning
○ Can be used in combination with Aglepristone (helps with luteolysis without giving contractions - don’t want contractions when closed - given 24 hours prior to PGF2alpha)
3) Treat bacterial infection
○ Broad spectrum antibiotic based on E. Coli
4) Treat systemic signs if indicated
pyometra prognosis for future fertility
- Dependent on age, parity, degree of CEH change, and response to treatment
- Reported pregnancy rates: 50-75%
- Reported recurrence rate: 10-80%
- If no response to treatment within 5 days
○ Poor prognosis in regard to future fertility
○ Increased risk of recurrence of disease - Prolonging anoestrus with androgen (mibolerone) recommended
What is the chance of pregnancy in a mating, therefore chance of bitch not falling pregnant and percentage for bitch missing twice in two consecutive cycle
- If a fertile male and a fertile female mate at appropriate time of cycle have a 75% chance of producing a litter
○ Therefore the bitch has 25% chance NOT to fall pregnancy per cycle
○ BUT only 6% of bitches miss twice in two consecutive cycles
When is fertility exam justified,, when done and the 3 main components
- Fertility exam justified after two empty consecutive cycles
○ Ideally first exam done in anoestrus (few months before next expected heat)
1) History
2) Generally physical exam and blood work
3) special reproductive exam
What history is important for a fertility exam in the dog
§ Signalment, esp breed and age § Environment - other dogs § Vaccination history, brucella canis tst § Complete medical history § Reproductive history □ Determine if she has: ® Normal oestrus cycle ® Irregular oestrus cycle ◊ Prolonged prooestrus/oestrus ◊ Shortened prooestrus/oestrus ◊ Shortened IEI (<4 months) ® Fails to cycle
What is important to consider with general physical exam and blood work in fertility exam of the dog
§ Acquired disease
§ Inherited diseases –> discourage from breeding if present
§ Baseline laboratory data
□ CBC/blood chemistry to exclude CUSHING’s
□ Urinalysis if sign of urinary tract infection
□ B.canis test
□ Supplementary
® TSH stimulation test if indication of hypothyroidism (no research that correlates this with infertility)
® Adrenal stimulation test if indicated
® Karyotyping if suspicious (ambiguous genitalia, primary anoestrus) - if had puppies then no
® Gonadotropin concentration if suspicious of hypogonadism
§ Follow-up exam might be necessary
What are important factors of special reproductive exams in assessing bitch fertiity
§ Abdominal palpation of uterus § Digital palpation of vulva and vagina when possible § Rectal palpation of vagina and bony pelvis § If applicable □ Ultrasonography □ Vaginoscopy □ Endoscopy □ Laparoscopy (with good indication)
Endometritis how diagnose,, best time to diagnose and treatment
- Controversial - does it exists
- History (>2 open cycles) together with positive intrauterine culture AND cytology are diagnostic
- Best time to diagnose: in dioestrus BUT luteolysis has to be initiated - give
- Appropriate antibiotics based on sensitivity
Oestrus induction what are 4 main indications and protocols
- Indications ○ Silent heat ○ Missed cycle ○ Limited male availability ○ Prolonged anoestrus - Various protocols available ○ Deslorelin (GnRH agonist) works well if given as implant or long acting injection
Follicular cysts how diagnose, confirmation and treatment
- Diagnosis based on history and u/s
- Need to confirm that the cycle is prolonged —> cytology
- Ultrasonography: follicles fail to luteinise; > 8mm diameter
- Treatment: GnRH or hcG
Always think of ovarian NEOPLASIA as a differential diagnosis
Vaginitis what are the 2 types, clinical signs and treatment
- Puppy vaginitis: Prior to first oestrus -> once goes away can spay
- Adult vaginitis: AFTER first oestrus and in spayed females
- Clinical signs: discharge, may attract male dogs
- Treatment: puppy vaginitis often resolves spontaneously after first oestrous cycle
- check for brucellosis
- Phenylpropanolamine recommended for adult vaginitis
Split heat what age common, what occurs and treatment
- Common phenomenon in young bitches during first heat
- Physiological and behavioural signs of prooestrus occur without progression to oestrus
○ Discharge -> so pyometra is a differential however that generally older this younger animals - After 4 weeks “normal oestrous cycle” with ovulation occurs
- Generally only occurs once and after that get normal oestrus
shortened IEI interval what leads to, cause and treatment
- IEI < 4 moths, subsequent infertility
- Can be breed related; especially German Shepherds affected
Treatment: delay oestrus with androgens (mibolerone)
Exogenous steroid hormones how common, what is banned and others used
- Have been used extensively in small animal reproduction
- Especially oestradiol and progestagens (delaying oestrus)
- BUT side effects make most uses OBSOLETE - BANNED
Androgens - Mibolerone
○ Not registered for breeding bitches but it is the recommended drug to delay onset of oestrus; start at least 1 month before onset of next oestrus - Testosterone propionate
○ Commonly used in racing greyhounds
Androgens are contraindicated in praepuberal bitches and dog with renal or hepatic disease
Ovarian remnant syndrome what occurs, clinical signs, diagnosis
important
- Piece of ovarian tissue left behind at the time of spaying
- Bitches present with signs of prooestrus (+/- bleeding)
- Can do hcG/GnRH stimulation test
- Laparoscopy during oestrus or luteal phase
List 3 ways can determine whether dog is spayed
1) Tattoo in ear
2) Incision midline - could be other things
3) FSH/LH test -> will be high -> no negative feedback from ovaries
Snap-test
what is the prostate and function
- Major accessory sex gland in the dog
○ Prostatic fluid is transport and support medium for sperm during ejaculation
○ Prostatic fluid reflux -> fluid produced leaks into bladder or out of penis
what are the 3 phases in prostatic development
I - embryonic and juvenile development
II - hyperplasia and hypertrophy in dogs 2.5 to 12 years
- Increases in weight
- Dependent on continuous androgen secretion
○ 5-alpha-dihydrotestosterone (DHT) is active androgen at intracellular level
III - senile involution in dogs >12 years
What is are the 3 main prostatic diseases and 3 that come secondary commonly
1) Neoplasia - more common in castrated dogs, malignant adenocarcinoma most common - grave prognosis
2) prostatomegaly
3) Benign prostatic hypertrophy/plasia (BPH)
- 90% of intact male dogs will have
- Increase in intraprostatic oestrogen: androgen ratio
- Easy to fix - CASTRATION
SECONDARY
- Often secondary to BPH therefore CASTRATION CURATIVE
1. Prostatitis - acute or chronic ->
2. Prostatic abscesses - often secondary to prostatitis
3. Prostatic cysts
prostatomegaly main clinical signs
- Dripping blood from penis
- Haematuria
- Haemospermia
- Tenesmus
- Dysuria
- Poor semen quality/infertility
- In acute prostatis: fever, anorexia, lethargy
Prostatomegaly diagnosis and treatment
Diagnosis
- Rectal palpation: size, symmetry, surface, pain
- Radiography
- Cytology and culture of prostatic fluid - Retrograde cysturethrography
- Urinalysis
- Ultrasonographically guided fine needle aspirate and/or biopsy)
Treatment
- CASTRATION
- If breeding animal
○ Finasteride (5 alpha reductase inhibitor) or progesterone until breeding “career” is over
○ Consider freezing semen
cats what is needed for mating and what is special about oriental breeds
Need to mate MULTIPLE times in order to ovulate
- Postcoital yowl - is characteristic of cat breeding
- Tomcat’s penis - has a band of 120 to 150 androgen-dependent spikes
○ If no spikes than castrated, if cryptorchid then can still have spikes
- Oriental breeds -> sometimes are spontaneous ovulators and therefore have a higher risk of pyometra
what occurs with cats if mated
- If mated then will get LH surge and increase in progesterone and ovulation
§ If mated and ovulate and do fall pregnant will stay on heat until parturition
§ If mated and ovulate and don’t fall pregnant can have pseudo-pregnancy so progesterone levels remain high but not as long as they do in dogs
what occurs with cats if not mated
- If not mated within the heat of the week will go into post-oestrus for a week (not on heat), oestrogen and progesterone levels are low
§ Then New follicular wave will occur increase oestrogen and then will go through week of heat, if not mated repeat cycle
What are the 2 main differentials for a mammary growth in a cat
- Fibroadenomatous hyperplasia ○ Involved the whole mammary gland and generally symmetrical unlike mammary neoplasia ○ If spay should go down - Mammary neoplasia ○ Most commonly malignant unlike dogs
what is the neonatal and pediatric period and what are the 2 important considerations with anaesthesia
○ Neonatal period extends for the first 6 weeks of life
○ Paediatric period for the first 12 weeks
1) Limited organ reserve
2) Exaggerated or prolonged effects of anaesthetics
List the 4 main major physiological differences affecting organ function with neonates
1) cardiovascular system
2) sympathetic nervous system not fully developed
3) respiratory system
4) thermoregulation
In terms of cardiovascular system what is different with neonates
○ Low myocardial contractile mass - thinner myocardium
○ Low ventricular compliance
○ Stroke volume and cardiac reserve are limited -> cannot increase contractility so drugs that do this are useless
§ Cardiac output is heart-rate dependent
○ Persistence of the foetal circulation in foal for up to 3 days (right-to-left shunt)
In terms of sympathetic nervous system and thermoregulation what is different with neonates
Sympathetic nervous system not fully developed
○ Minimal increase in heart rate and myocardial contractility → further impairing ability to increase cardiac output
§ May not be able to increase the CO to suitable level
§ Can still use atropine
○ Poor vasomotor control and inadequate response to blood loss -> more hypovolaemic than others
Thermoregulation
○ Immature thermoregulatory system
○ High body surface to mass ratio -> very important to keep warm during procedures
→ Prone to hypothermia
In terms of respiratory system what is different with neonates
○ Pulmonary reserve is minimal
○ More compliant chest → greater work of breathing (when create negative pressure air moves in as well as ribs (decreasing the pressure gradient) therefore not as efficient - will need to increase respiratory rate)
○ High minute volume as more dead space -> more breaths but gas exchange not as efficient so need the higher minute volume (how much volume inspire per minute)
List 6 main major physiological different affecting pharmacological properties of anaesthetic and what properties does this affect
- Hypoalbuminemia → more free drugs as most drugs are more than 90% protein bound (except morphine 50% bound)
- Increase permeability of the blood brain barrier → more drugs getting to the brain
- Low body fat percentage → less drug redistribution in adipose tissue - especially for drugs such as thiopentone
- Mature hepatic metabolism → increase duration of action -> ketamine is metabolised in liver
- Immature glomerular filtration rate (neonate) → increase duration of action
- Higher metabolic rate → increase oxygen consumption and carbon dioxide production
What are the 4 main things needed for adequate anesthetic protocols
- Sedative
- Muscle relaxant
- Analgesia
- Hypnotic
What are 6 important components of adequate anaesthetic protocol when neutering
1) fasting (limited in paediatric patients)
2) intra-muscular anaesthetic premedication
3) intravenous anaesthetic induction
4) anaesthetic maintenance
5) loco-regional analgesia
6) post-operative analgesia
in terms of intra-muscular anaesthetic premedication and intravenous anaesthetic induction for YOUNG ADULTS NEUTERING what are 3 different protocoals for each
Intra-muscular anaesthetic premedication
1. Medetomidine (NOT IN PAEDIATRIC PATIENT) & methadone (dogs and cats)
2. Or acepromazine (not good sedative in cats) methadone (dogs)
3. Or ketamine (when use HAVE to combine with muscle relaxation) & midazolam (good absorption via IM) & methadone (cats)
Intravenous anaesthetic induction
1. Propofol +/- diazepam
2. Or alfaxalone +/- diazepam (IV cannot be given IM)
3. Or diazepam & ketamine
What is involved with anaesthetic maintenance, loco-regional anaglesia and post-operative anaglesia for NEUTERING YOUNG ADULTS
Anaesthetic maintenance
○ Isoflurane in oxygen
○ Balanced Crystalloid solution (2.5 to 5 ml/kg/h)
Loco-regional analgesia
○ Line block with bupivacaine or ropivacaine - longer duration effect than lignocaine - CANNOT GIVE IV
○ Intra-testicular block with lignocaine (dogs)
Post-operative analgesia
○ NSAID (carprofen or meloxicam)
○ +/- Opioid
in terms of intra-muscular anaesthetic premedication and intravenous anaesthetic induction for NEUTERING PAEDIATRIC PATIENTS what are 3 and 2 different protocoals
Intra-muscular anaesthetic premedication
○ Acepromazine (low dose) & methadone (dogs and cats)
○ Or Acepromazine & Hydromorphone (dogs)
○ Or ketamine (low dose) & midazolam & methadone (cats)
Intravenous anaesthetic induction
○ Propofol +/- diazepam
○ Or alfaxalone +/- diazepam
What is involved with anaesthetic maintenance, loco-regional anaglesia and post-operative anaglesia for NEUTERING PAEDIATRICPATIENT
Anaesthetic maintenance
○ Isoflurane in oxygen
○ Balanced Crystalloid solution
○ +/- 5% dextrose solution at 2 to 5 mL/kg/hour
Loco-regional analgesia
○ caution to the total volume administered
○ Line block with bupivacaine or ropivacaine
○ Intra-testicular block with lignocaine (dogs)
Post-operative analgesia
○ NSAID (carprofen or meloxicam) - NOT IN NEONATES (don’t use until liver is matured)
○ +/- Opioid
What are the 3 main cardiovascular affects induced by pregnancy
1) Estrogens decrease vascular resistance, combined with increased Cardiac Output
○ Blood pressure unchanged
○ HR and SV ↑
○ Less reserve in cardiovascular function -> problem when stressed
2) Blood volume ↑ up to 40%
○ Plasma > RBC’s (RBCs number stays the same) = Decreased PCV
○ Decreased PCV = Decreased [Hb]
3) Cardiovascular Changes during Labor
○ ↑ HR, CO, BP, and CVP (central venous pressure)
○ Oxytocin levels rise
Vasodilatio
What are the 4 main respiratory affects induced by pregnancy
1) Progesterone increases CNS sensitivity to CO2
○ “Normal” PaCO2 decreased to ~30 mmHg
○ Increased minute ventilation due to increased respiratory rate
2) Increased tissue oxygen demands (VO2)
3) Decreased functional residual capacity (FRC)
○ Gravid uterus pushes up on diaphragm = less space for lungs
○ More sensitive to hypoxemia and hypercapnia
4) ↓ FRC + ↑ minute ventilation = Faster Induction with Inhalants
What are the main gastrointesintal, hepatic/renal and uterine affects induced by pregnancy
Gastrointestinal - Gravid uterus pushing on stomach ○ Decreases gastric motility ○ Decreases esophageal sphincter tone -> Risk of regurgitation increased and aspiration pneumonia Hepatic and Renal - Increased hepatic and renal blood flow ○ GFR increased by up to 60% ○ BUN and creatinine decreased Uterine - Uterine Blood Flow increases during pregnancy and labour - Uterine contraction and oxytocin decrease uterine blood flow => decreased foetal viability, effect worsen by anaesthesia
List 4 conditions that favour drugs crossing the placenta and what are these qualities good for
- Poor ionization (in the dam)
- Low molecular weight (<500 daltons)
- Low protein binding
- High lipid solubility
All qualities of a Good anaesthetic drug BUT all Bad for the foetus!!!
How does foetal pH affect drug distribution
Fetal pH is 0.1 units LESS than the dam!
- if drug is weak base (opioid and local anesthetics) then get higher concentration in fetus = ION TRAPPING!
○ Now cannot cross back to the maternal circulation -> accumulation of drugs within the foetus
What are important considerations with caesarean section
- drugs will accumulate within the foetus so want to stop this as much as possible
○ Be prepared and quick
○ Use smallest doses possible
○ Consider local anaesthetics
○ Avoid long acting drugs
○ Choose reversible drugs if possible - NOT ACE (vasodilation within cardiovascular immature animals and will last long) - Minimize inhalant concentration (reduced MAC in pregnancy) -> vaporiser setting lower
- Dam is at increased risk for vomiting and regurgitation
What equipment and drugs is needed for neonates during casearean
○ Equipment includes:
§ Warming devices, towels, OXYGEN, intubation kits, dry gauze to wipe secretions from mouth/nose
○ Emergency drugs: Reversal agents (for dam and puppies), Epinephrine, Atropine, Dextrose
Casearean what premedications use and don’t use and what is importnat to remember
- Opioids - controversial
○ Look for minimal respiratory effects versus analgesia
○ => low dose methadone or pethidine - Avoid acepromazine or alpha-2 agonists
○ If necessary, small dose of alpha-2 can be reversed after induction
○ Xylazine is an identified risk factor for neonatal mortality - This is one instance where I may “skip” the premed
- Remember to pre-oxygenate the patient!
What are the pros and cons of using opioids in casearean premedications
Pros
- Less anaesthetic
- Less cardiovascular side effects on dam and neonates
Cons
- Respiratory depression -> when get to foetus result in increased depression of respiratory system
What is important for maintenance with caesearians
- Propofol / Isoflurane or Sevoflurane
- Likely to require IPPV (due to dorsal recumbency)
- Consider additional analgesics after removal of puppies or kittens
- Don’t forget local analgesia
- Ephedrine maintains uterine blood flow while treating hypotension
What is important with puppy or kitten and casearian resuscitation
- Oxygen is the single most important thing you can provide!
- Rub vigorously to stimulate breathing
- Do NOT “sling” puppies!
- Doxapram (stimulate breathing) controversial - under tongue if no spontaneous breathing after oxygen and rubbing
- Provide warmth and continued high oxygen environment
- Reversal of the drugs given to the dam that could have transferred to the puppies through the placenta
What are 4 important things to do with recovery after caesearian
1) Get puppies or kittens nursing on dam as soon as possible
○ Try to avoid “over-sedation” of dam as she could suffocate newborn
2) Assign someone to watch dam with newborns
○ Dams (especially with first litter) may try to EAT the newborns!
3) NSAIDs (not high doses as can transfer into milk) +/- Tramadol for dam for post-op pain
4) Get dam and litters out of your hospital ASAP!!!
What are the 5 important diagnosis techniques for skin disease and equipment needed
- Tape prep - acetate tape
- Skin scrapes (superficial and deep) - 22 scalpel + paraffin oil
- Impressions smears - glass slides
- Trichograms - mosquito haemostats
- FNAs - 22g needle + 5ml syringe
What are the 3 important aspects of diagnosis of skin disease and what is critical to diagnosis
- Right test for the right lesion
- How to collect the sample
- How to interpret
CYTOLOGY - must have oil immersion lens microscope - condenser down and iris closed
Alopexia what are the 2 main reasons this occurs, reasons within and what diagnostic processes need to do
Process/causes 1. XS loss 2. Failure to grow DDx • XS loss ○ Self-trauma ○ Folliculitis - inflammation of follicle § Parasites, bacteria, fungal • Failure to grow ○ Endocrinopathy - Cushing's disease Diagnostic approach • Signalment (age) • History (self trauma) - Diagnostics ○ Trichograms and skin Scrapes needed
What is involved with trichograms
Grab the edge of the lesions, 20 hairs at the base
Will hurt
Parafin oil on the slide
Line up the hair - all tips down on end and top down the other
Look at the tips of the hair
In terms of skin scraping what parasites except to diagnose in superficial and deep and technique
- Superficial
a. Sarcoptes
b. Cheyletiella
c. D. canis (short body)
d. Trombic ula
e. Lynxacrus radovsky
f. Dermanyssus gallinae - Deep
a. D. canis - Demodex canis
b. Long bodied
Technique - Clip skin - large area
- Apply paraffin on scalpel blade, on slide
- Scrape wide area
Tips for doing a skin scrap
- Squeeze skin
- Paraffin oil
- Scrape until capillary oozing present -> scrap firmly
○ Should blunten the scapel blade - Mix additional mineral oil
- Cover slip on
- Condenser down
Papules and crusts what are they, 3 main causes and how to diagnose
- Papules - pruritic and scratching
- Crust - pustule that has ruptured
All time variations of the SAME lesion
Causes - infection
- immune mediated
- Allergy
Diagnosis
1. Impression smear
○ Moist / greasy lesions of flat areas
○ After crust removed
○ After rupturing pustule or vesicle
2. Scalpel blade cytology
○ Dry papules
THEN - stained cytology
Dry scaley or greasy skin what diagnostic techniques needed and how to conduct
sticky tape preparation and skin scraps
- Generally have a lot of infection
Sticky tape preparation
- Stained on glass slide
- Look at straight away under low power and scan for neutrophils
Either neutrophils for damage of skin OR infection
Nodules what are important signalment, history and diagnostic techniques
- Signalment ○ Age (neoplasia risk) ○ Breed (neoplasia risk) - History ○ Speed of lesion growth ○ Hunting/ activities - Diagnostics ○ Fine needle aspirate § Nodules, tumor's, cysts § Not aspirating vs aspirating □ Not aspirating - mast cell tumour □ Aspirating - epithelial tumor - FNA give diagnosis and specific treatment OR logical next step (histopathology, biopsy and deep tissue culture/PCR)
