614 - Small Animal Practice T2 Flashcards
What are some precautions that need to be taken when giving infectious vaccines?
Dont give them to pregnant queens or bitches
They may revert to virulence once injected (though it is uncommon)
Need to be careful about aerosolisation of vaccine especially cat flu vaccine
What is a non-infectious vaccine?
An inactivated but antigenically intact virus or organism combined with an adjuvant.
They provide less robust immunity than live, and generally have a shorter DOI than infectious vaccines.
It won’t rever to virulence and usually required multiple doses to induce protection.
Give some examples of adverse vaccine reactions.
Pain on injection
Swelling at the injection site
Persistent lump at injection site
Granuloma development + possible progression to feline injection site sarcoma (FISS) in cats
Generalised malaise, fever, inappetence
May have localised or generalised anaphylaxis.
IMHA (in dogs), ITP (in cats)
Which vaccines are most commonly implicated in the formation of FISS?
Rabies, FeLV, FIV
What are the fundamental concepts of the WSAVA guidelines?
Aim to vaccinate every animal with core vaccines to provide herd immunity
Non-core vaccines should be given no more frequently than is deemed necessary
Name the core vaccines for dogs.
Canine distemper virus (CDV)
Canine adenovirus (CAV)
Canine parvovirus type 2 (CPV-2)
+ Rabies if in an endemic area
Name the core vaccines for cats.
Feline enteritis/feline parvovirus (FPV)/feline panleukopenia
Feline calicivirus (FCV)
Feline herpesvirus-1 (FHV-1)
+ Rabies if in an endemic area
Name the NON-CORE vaccines for dogs.
Bordetella bronchiseptica + canine parainfluenza virus
Leptospirosis
Borrelia/Lyme disease
Name the NON-CORE vaccines for cats.
Feline leukaemia
Chlamydopila felis
FIV
Why is the FIP vaccine not recommended?
It will only protect cats which are coronavirus antibody negative - which is unlikely after 16 weeks of age because of how common and widespread coronavirus is.
What is the standard puppy vaccination regime for a C3 and why do we vaccinate at these intervals?
6-8 weeks old - doesn’t actually do that much for immunity unless the puppy has low MDA
10-12 weeks old - MDA are starting to wane + have less intereference on core vaccine efficacy
14-16 weeks old - MDA will be at almost negligible levels by this stage
Core vaccines should be boosted at 6 months (instead of 12-15) to capture non-responders.
How, why and in what circumstances is titre testing useful?
Titre testing tests for seroconversion so will tell us if there is vaccine failure (in which case we can try a different brand) or if there is a need for a booster vaccine when trying to minimise how many vaccinations we are giving (i.e. trienniels, extended duration of immunity of CORE vaccines). There are only titre tests available for CPV, CDV + canine adenovirus via UK.
We can also titre test animals with adverse vaccine reaction history to decide if we need to vaccinate them again or if they are sufficiently covered and we don’t have to risk more adverse reactions - however, most adverse reactions are from kennel cough vaccine and there isn’t a titre test for that currently.
We don’t titre test in cats.
What are the causes of vaccine failure?
Presence of MDA
Improper vaccine handling and administration
Vaccine is poorly immunogenic
Host factors lead to poor response
Insufficient time to develop immunity prior to exposure
Discuss the routes of administration of canine kennel cough vaccine and what they cover.
Infectious vaccine - intranasal or intraoral
Non-infectious vaccine - parenteral/SC
Intranasal - Bordetella and canine parainfluenza virus
Intraoral - Bordetella, if giving in this route you need to also give parenteral parainfluenza coverage.
Discuss a regime for extended DOI in cats.
Year 1: Tricat - to cover herpesvirus, calicivirus (both annual) + panleukopaenia (triennial)
Year 2: Ducat - covers herpes + calicivirus
Year 3: Ducat
Year 4: back to Tricat
NEED TO GET INFORMED CONSENT because this is off-label use.
Which populations of cats might we want to give the FIV vaccine? How about the vaccine for Chlamydophila felis?
FIV - cats that are out and able to fight with other cats, especially ferals
Chlamydophila felis - catteries prior to introduction of a new cat
How do we deal with live vaccine spillage on a cat?
Clean it off with isopropyl alcohol - it inactivates live virus and won’t damage the cats mouth when they inevitably groom themselves later
Describe the pathogenesis of cat bite abscesses.
Injection of oral bacteria under the skin by biting or scratching –> neutrophil + phagocyte infiltration –> pus formation –> body walls off the infection = abscess
May burst spontaneously if pressure necrosis of the dermis occurs
What is the clinical presentation of a cat bite abscess?
Grumpy cat, possibly lame and painful
Pyrexic (esp. in first 12 hours)
May not have an overt mass, may have cellulitis
Regional lymphadenopathy
Discharging area with necrotic skin
Discuss treatment and management of a cat bite abscess.
If new bite wound or cellulitis - 1 wk course of Ab (generally amoxyclav or doxycycline) + pain relief (meloxicam)
If cellulitis but no abscess - as above.
If abscess - surgical drainage, GA + debride necrotic skin, flush dead space with saline or dilute betadine, close wound but not SC layer +/- drain; then 1 wk Ab + meloxicam, remove sutures 7-10d post-op
Which 2 bacteria are most likely to be transmitted to humans from a cat bite?
Pasteurella, Porphyromonas
Name the common sites for grass seeds to implant themselves.
Ear canal, nasal cavity, eye under conjunctiva, interdigital, skin of ventral abdomen or thorax, ventral mandible, prepuce, vulva
How do we treat grass seed foreign bodies?
Remove them! - find the tract and gently probe
Debride necrotic tissue and flush with saline if possible
Closure for abscess but may not be necessary
Antibiotics if soil microbes involved - Amoxil, amoxyclav
What is atresia ani?
Rare congenital abnormality, born without an anus, poor prognosis –> euthanasia.
What are the clinical signs of common anal sac conditions?
Impaction - full anal sacs, pain, discomfort, scooting
Sacculitis/inflammation - sac enlargement, perianal redness, swelling, pain, +/- pyrexia + tenesmus
Abscess - pyrexia, swelling, pain, discharge, blood and/or purulent material, +/- discharging sinus + tenesmus
What are the 3 main DDx for scooting?
Perineal pruritis, tapeworm infection, full anal glands
How do we treat anal sacculitis?
GA, insert a 23g catheter into the duct + gently flush with saline til contents are clear
Instil AB/steroid cream into the sac till its full
How do we treat anal sac abscessation?
GA, insert 23g catheter into the duct + gently flush with saline until contents are clear, treat the abscess surgically
AB (cephalexin, clindamycin, amoxyclav) for 10-14d
Define heart failure.
Any condition whereby cardiac output is insufficient to deliver adequate blood to meet metabolic demand at normal cardiac filling pressures.
List the presenting complaints associated with cardiac dysfunction.
Dyspnoea, tachypnoea, pulmonary oedema, pleural effusion
Syncope
Exercise intolerance
Cough
“Paralysis”
Ascites
Cyanosis
Poor perfusion/prolonged CRT
Poor growth or weight loss
Blindness
Heart murmur
What are the signs of heart DISEASE?
Any sign that indicates an abnormality within the heart - it does not imply that failure is present.
Murmur
Arrhythmia
Diagnostic imaging change
What are signs of heart FAILURE?
Poor cardiac output - tachycardia, inc. force of contraction, loss of sinus arrhythmia with dec. vagal tone, vasoconstriction (poor peripheral perfusion, cold exremities, pale MM), blood volume expansion + prolonged CRT
Left sided congestion - pulmonary oedema (crackles), pleural effusion in cats (dull ventral lung sounds +/- paradoxical breathing), cyanosis, tachypnoea, restrictive breathing pattern (rapid + shallow), cough
Right sided congestion - jugular pulses, ascites, hepatomegaly, pleural effusion in dogs (dull ventral lung sounds, tachypnoea, cyanosis, restrictive breathing pattern +/- paradoxical breathing), hepatojugular reflux, cachexia
Discuss what should be included in the description of heart auscultation findings.
- RATE
- RHYTHM
- AREA
- AUDIBILITY
- ADVENTITIOUS SOUNDS
How are murmurs classified?
- LOUDNESS - grades 1 to 6
- TIMING - systolic, diastolic, continuous
- LOCATION - left or right, base or apex
What is your main differential for a left apical systolic murmur?
Mitral regurgitation
What is your main differential for a left basal diastolic murmur?
Pulmonic or aortic regurgitation
What is your main differential for a right apical diastolic murmur?
Tricuspid stenosis (TS)
What is your main differental for a left basal continuous murmur?
Patent ductus arteriosus (PDA)
What is your main differential for a left basal systolic murmur?
Pulmonic stenosis (PS), subaortic stenosis (SAS), atrial septal defect (ASD)
What is your main differential for a right basal systolic murmur?
Subaortic stenosis (SAS)
What is your main differential for a right apical systolic murmur?
Tricuspid regurgitation, ventricular septal defect (VSD)
What is your main differential for a left apical diastolic murmur?
Mitral stenosis
Which cardiac biomarkers are available for animals and what are they increased with?
Cardiac Troponin I - inc. with myocyte injury and myocarditis
NT-proBNP/Brain Natriuretic Peptide - inc. with myocyte stretch + heart failure
What is the best ancilliary test for heart disease and failure?
Echocardiography (ECHO)
What ancilliary testing can we do for heart disease and failure?
Echocardiography
ECG + Holter recording
Thoracic US
Thoracic radiography
Blood pressure measurement
General CBC and biochem for pre-existing renal or electrolyte abnormalities
Cardiac biomarkers - cardiac troponin I and NT-proBNP
Angiography
In terms of murmur location - where might you hear dysfunction of each major heart valve?
Left base - aortic and pulmonic valves
Left apex - mitral valve
Right apex - tricuspid valve
What is the most common cause of heart failure in dogs?
Chronic valvular heart disease/myxomatous mitral valve disease/mitral valve disease/mitral valve degeneration/endocardiosis
What are the clinical signs of disease with chronic valvular heart disease?
Left sided apical systolic heart murmur
Cough due to LA enlargement and tracheobronchomalacia
Arrhythmia
List the potential sequelae of chronic valvular heart disease.
Chordae tendineae rupture (acute deterioration)
Arrhythmia - usually atrial fibrillation
Cardiac cachexia
Pulmonary hypertension (may see exercise intolerance)
Haemopericardium in severe cases when the LA ruptures
Progression to non-responsive heart failure
If you were suspicious of heart failure and wanting to do thoracic radiography, what view do you NOT want to do?
VD
What changes do you expect to see on acilliary testing and imagery in a dog with chronic valvular heart disease?
Thoracic rads - LA enlargement with LA wedge (may have other chamber enlargement too), pulmonary oedema, signs of mainstem bronchus compression, pulmonary venous distension
Thoracic US - in LSCHF –> perihilar B lines + more diffuse B lines; in RSCHF –> pleural effusion
Echo - +/- valve flail, LA enlargement, valvular regurgitation + pulmonary hypertension on Dopplet
ECG - sinus tachycardia in failure, wide P waves from LA enlargement, tall wide QRS from LV enlargement, intermittent supraventricular tachyarrhythmias, atrial fibrillation
Briefly describe the different stages of CVHD.
Stage A - predisposed but no identifiable structural abnormalities
Stage B1 - structural heart disease present but clinical signs of heart failure have never developed and there is no imaging evidence of remodelling
Stage B2 - structural disease present but clinical signs of heart failure never developed, imaging evidence of remodelling
Stage C - past or current evidece of heart failure present
Stage D - clinical signs of heart failure refractory to standard therapy
At what stage of CVHD do we start the dog on treatment and what is it?
Stage B2 - pimobendan and mild sodium restriction, maintain optimal BW/condition
What are the treatments for Stage C CVHD?
Furosemide +/- monitor renal values and electrolytes after a few days
Could also use spironolactone
Oxygen
Cage rest
Pimobendan +/- ACE inhibitors
Drain effusions if compromising respiration
Judicious sedation + anxiolysis
Vasodilators
Dobutamine
Treat arrhythmias
Dietary modification - modest sodium restriction, optimise caloric intake to prevent cardiac cachexia
+/- Cough suppresants (if the cough is impacting their quality of life)
Monitor BW, appetite, RR + HR
Discuss the clinical signs of pulmonary hypertension, how to diagnose it, and what drug we can use to treat it (other than treating the underlying cause).
Cx - syncope, dyspnoea, RSCHF signs, +/- RS tricuspid murmur, split S2 sound
Dx - ECHO
Tx - sildenafil
What additional therapies can we consider to try and give a dog in Stage D CVDH some relief?
Higher doses of furosemide or change to torsemide (which is stronger)
Pimobendan x3/day
Additional diuresis
Vasodilators
Cough suppressants
Anti-arrhythmics
Sildenafil (for pulmonary hypertension)
Short term mechanical ventilation
What 2 valves are commonly affected in infective endocarditis?
Aortic and mitral valves
Describe the clinical signs of infective endocarditis.
New/sudden onset murmur - usually diastolic (aortic regurgitation)
Pyrexia
Other areas of infection present
Bounding pulse
What are the 6 criteria of diagnosis for infective endocarditis. Differentiate which 3 are major vs minor criteria.
MAJOR:
1. Positive ECHO findings - vegetative lesions, destructive lesions, thickened aortic valve leaflets
2. Positive blood cultures or sepsis - 3 positive blood cultures of common skin contaminants, 2 positive cultures of other organisms
3. Recent onset of a diastolic heart murmur
MINOR:
4. Pyrexia
5. Large dog, over 15kg
6. New or worsening systolic heart murmur
Discuss the treatment and prognosis for dogs with infective endocarditis.
Tx - initial parenteral ABs, oral ABs for 4-6 weeks (choice based upon C&S results), empirical ABs (amoxyclav AND fluoroquinolones OR gentamicin), treat CHF as necessary (furosemide + pimobendan)
Prognosis - poor, death is usually from CHF, embolisation or sepsis
Which breeds are predisposed to idiopathic dilated cardiomyopathy (IDCM) in dogs?
Boxers, Great Danes, Newfoundlands, Saint Bernard, Irish Wolfhound, Dobermann, American Cocker Spanial
Contrast the clinical signs associated with occult disease and clinical failure in dogs with IDCM.
Occult disease - arrhythmia (commonly tachyarrhytmias, ventricular tachycardia in Dobermann and Boxers, A Fib in giant breeds and late stage dx), murmur (left apical systolic), ECHO screening
Clinical failure - structural or electrical changes, left or right sided CHF signs, decreased cardiac output signs (syncope is super common)
What echocardiographic findings are associated with idiopathic dilated cardiomyopathy (IDCM) in dogs?
Increased LV diameter
Rounging of LV lumen
Increased LA size
Increased E point to septal separation (EPSS)
Decreased fractional shortening
Wall thinning apparent in advanced disease
What thoracic radiographic findings are associated with IDCM in dogs?
Generalised enlargement of cardiac silhouette - Dobermann and Boxers may have minimal cardiomegaly
Pulmonary oedema, pulmonary vein distension if LSCHF
Pleural effusion if RSCHF
Discuss the treatment of dogs with IDCM.
ACUTE CHF:
Furosemide
Oxygen
Cage rest
Pimobendan +/- ACE inhibitors
Drain effusions if compromising respiration - thoracocentesis
Judicious sedation (butorphanol will dec. oxygen demands)/anxiolysis
Vasodilators
Dobutamine (to stabilise in acute stage)
+ treat arrhythmia if necessary
CHRONIC CHF:
Pimobendan +/- ACE inhibitors
Furosemide +/- spironolactone +/- thiazide
Salt restricted, high energy diet
Exercise restriction until their condition is under control
Carnitine and taurine in selected breeds
VENTRICULAR ARRHYTHMIAS:
Acute - lidocaine
Chronic - mexilitine, sotalol
ATRIAL FIBRILLATION:
Digoxin +/- Ca channel blocker
What drug class can be used as an antiarrhythmic but should NOT be used in heart failure.
Beta blockers
What breeds commonly get pericardial effusion?
Golden retriever
GSD
Describe the typical history, clinical signs and physical exam findings of pericardial effusion.
History and Cx - if chronic then lethargy, anorexia, weakness, collapse, tachypnoea, muscle wastage/weight loss, RSCHF signs, exercise intolerance; if acute onset then collapse, cardiogenic shock + death
Physical Exam - muffled heart sounds, ascites, pleural effusion, dull ventral lung sounds, jugular venous distension, tachycardia, weak pulses, pulsus paradoxus (weaker pulse during inspiration)
Describe which ancilliary tests are going to be useful in diagnosing pericardial effusion and the findings you would expect.
ECHO - diastolic collapse of RA and/or RV confirms cardiac tamponade, try to identify neoplasia
Thoracic radiography - mild to severe enlargement of cardiac silhouette, rounded or globoid cardiac silhouette, sharp edges, +/- pleural effusion
ECG - sinus tachycardia, low voltage QRS complexes
Describe appropriate treatment for a dog with pericardial effusion.
Pericardiocentesis
IV fluid therapy until performed if clinically necessary
NO diuretics
Name 2 neoplasias that cause pericardial effusion.
Haemangiosarcoma of the right atrium
Chemodectoma
Other less common ones - mesothelioma, ectopic thyroid carcinoma, metastatic neoplasia
What are the 6 phenotypes of feline cardiomyopathies?
- Hypertrophic
- Dilated
- Restrictive
- ARVC
- Non-specific
- Idiopathic (primary) or secondary
Describe the possible presentation of feline heart disease.
Severe dyspnoea - pleural effusion or pulmonary oedema
Sudden death
Acute hind limb paralysis
Murmur or gallop rhythm detected at routine vaccination
What are potential causes of progression of feline heart disease from stage B2 to C?
Stress
Intravenous fluid therapy (IVFT)
Glucocorticoids
General anaesthesia
Often none identified
Which breeds of cat are predisposed to HCM?
Maine Coon
American Shorthair
Discuess the pathophysiology of hypertrophic cardiomyopathy in cats.
Its typically a symmetric hypertrophy of the left ventricular free wall and interventricular septum, although asymmetric hypertrophy can occur.
Hypertrophy causes diastolic dysfunction including decreased cardiac output (tachycardia, poor pulses, cold extremities), and left sided congestion (LA enlargement, pulmonary oedema, pleural effusion).
Systolic anterior motion of the mitral valve is common.
Describe the expected physical examination findings of hypertrophic cardiomyopathy.
+/- murmur - parasternal usually, not consistently present
+/- gallop rhythm
LSCHF - tachypnoea, laboured breathing, pulmonary oedema (crackles), pleural effusion (dull lung sounds ventrally, paradoxical breathing pattern)
Dec. CO signs - tachycardia, cold extremities, weak pulses, hypothermia
Arrhythmias
Aortic thromboembolism
Discuss which ancilliary testing we should do for idiopathic HCM in cats and the expected findings.
ECHO - increased wall thickness either generalised and focal, LA enlargement, assess LV outflow tract
Exclude secondary HCM - hypertension (measure SBP) and hyperthyroidism (total T4 concentration)
Thoracic radiography - cardiomegaly, Valentine heart shape (enlarged LA and left auricle cause bulge, apex shift to midline), CHF signs (pleural effusion, pulmonary oedema)
ECG - supraventricular or ventricular ectopic complexes
NT-proBNP cardiac biomarker - will be present
Explain the treatment of hypertrophic cardiomyopathy (HCM) in cats with severe, acute CHF.
Do minimal examination and allow them to calm and settle in a quiet room with no dogs, provide oxygen if its not going to stress them out more, can give butorphanol to help calm them.
If in stage B1 - no treatment
If in stage B2 - clopidogrel to try and minimise the risk of ATE (could also use aspirin or low MW heparin), treat arrhythmias if necessary
If in stage C - rest in stress-free environment, oxygen supplementation, furosemide, free access to water + monitor electrolytes, thoracocentesis if due to pleural effusion, sedation with butorphanol, pimobendan +/- dobutamine
To go home - lowest possible dose of furosemide, clopidogrel, pimobendan, can prescribe beta blockers but not if heart failure is present
Discuss the clinical signs, diagnosis, and treatment of dilated cardiomyopathy in cats.
Cx - congestive heart failure signs, retinal degeneration if because of taurine deficiency
Dx - ECHO, dietary history, plasma taurine
Tx - give taurine if deficient, pimobendan, heart failure treatment as normal
Explain the expected echocardiography findings for a cat with restrictive cardiomyopathy.
Diastolic dysfunction
Absence of hypertrophy of myocardium
Moderate to marked LA or bilateral dilation
Hyperechoic wall segments may indicate fibrosis
What are the risk factors for developing aortic thromboembolism (ATE)?
Any feline cardiomyopathies
Enlarged left atrium is a risk factor
May identify sluggish blood flow in the left atrium
May identify thrombus within the left atrium
What are the differentials for sudden onset hind limb paralysis in cats?
Aortic thromboembolism (ATE)
Snake envenomation
Trauma
IV disc disease
Spinal lymphoma
Fibrocartilagenous emboli
What is the most common site of thromboembolism in ATE?
Aortic trifurcation/iliac arteries (90%)
List the clinical signs of a cat with aortic thromboembolism (ATE).
Depends on the site of thromboembolism
Pain
Cardiac disease signs
Hypothermia
Cold extremities
Absent pulses
Cyanosis of pads and nail beds
Muscles may be painful, firm + swollen
Decreased cutaneous sensation and limb reflexes
Loss of motor function
How do we diagnose aortic thromboembolism in a cat?
Consistent clinical signs
Blood biochemistry - inc. AST and CK, stress hyperglycaemia, metabolic acidosis, azotaemia, hyperkalaemia
Peripheral vs central blood glucose - low glucose in affected limb
ECHO + colour flow Doppler of the aorta may be used to identify thrombus
Discuss the treatment of aortic thromboembolism in cats.
Supportive - analgesia, treat underlying heart condition, cage rest, IVFT, monitor electrolytes, monitor azotaemia
Thrombolytic therapy - streptokinase, tissue plasminogen activator
Prevent further clot formation - clopidogrel, low MW heparin, aspirin, oral factor Xa inhibitors (rivaroxaban)
Describe the typical innocent murmur.
Systolic, low grade (1-2/6)
Audibility varies with HR, body position, exercise, stress
Usually audible at the left sternal border, basal
Does not radiate
Confined to early or mid systole
Usually disappears by the age of 4-6 months old
What are the red flags in juvenile murmurs?
Late systolic, pansystolic, holosystolic, diastolic or continuous
Loud murmur (>3/6)
Apical or right sided murmur
Murmur radiates
Persistence of the murmur beyond 6 months of age
Additional signs of cardiovascular dysfunction - cyanosis, poor pulse quality, dyspnoea
Name the 3 most common congenital cardiac defects in dogs.
Patent ductus arteriosus
Pulmonic stenosis
Aortic stenosis
Name the 2 most common congenital cardiac defects in cats.
AV dysplasia
Ventricular septal defects
List the expected physical examination findings of a dog with PDA.
If LEFT to RIGHT shunt - continuous or machinery murmur left base, widened pulse pressure, precordial thrill common left heart base, LSCHF may occur
If RIGHT to LEFT shunt (rare) - cyanosis of caudal part of the body, erythrocytosis, loss of murmur
How do we diagnose congenital heart diseases?
Echocardiogram
Thoracic radiography
List the expected clinical signs of a ventricular septal defect (VSD).
Murmur on right parasternal edge, loud with small to moderate sized defects, soft with large defects
LSCHF common though right sided can occur
Cyanosis
What types of stenosis are there and what breeds are predisposed?
Pulmonic stenosis - valvular, subvalvular, supravalvular: English bulldog, Boxers, Beagles
Aortic/subaortic stenosis: Newfoundlands, Golen retrievers, Boxers
List the clinical signs of pulmonic stenosis.
Ejection murmur left heart base
Exertional fatigue
Weakness
Syncope
Pulse strength often fair
RSCHF signs - ascites