Cardiorespiratory Diseases
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Transcript Cardiorespiratory Diseases
Cardiorespiratory Diseases
• 4 Chambers
Heart Chambers
– R atrium
• Receives deoxygenated blood from body
– Vena cava
– R ventricle
• Pumps deoxygenated blood to lungs
– Pulmonary artery
– L atrium
• Receives oxygenated blood from lungs
– Pulmonary vein
– L ventricle
• Pumps oxygenated blood to body
– Aorta
Cardiorespiratory Physiology
• R side of heart
– Blood
• Low O2
• High CO2
– Pressure
• Low—short distance to lungs
• L side of heart
– Blood
• High O2
• Low CO2
– Pressure
• High—far distance to body
Alveoli-Capillary Gas Exchange
• Alveoli surrounded by capillaries
– Incoming RBCs low in O2
– Exiting RBCs rich in O2
– Thin capillary membrane (epithelium?)
• SA node
Electrical Conduction of Heart
• Pacemaker (fastest rate of contraction)
• In R atrium
• AV node
• Impulse travels along internodal tract
• Slight delay
– Filling of ventricles
• Bundle of HIS
– Interventricular septum
• Purkinje fibers
– To myocardial cells
– Apex contracts first
Electrocardiogram (ECG)
• P wave
– Contraction of atria
Measures electrical activity
of heart at skin surface
• QRS complex
– Contraction of ventricles
– Repolarization of atria (hidden by vent activity)
• T wave
– Repolarization of ventricles
Cardiovascular Diseases
• Heart Failure—returning blood is not pumped fast enough to meet
body’s needs
• Heart failure is not a heart attack
– 2 causes
• Myocardial (heart muscle) dysfunction
– Cardiomyopathy
– Myocarditis
– Taurine (an amino acid) deficiency in cats
• Circulatory failure
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Hypovolemia (shock, hemorrhage, dehydration)
Anemia
Valvular dysfunction
Congenital shunts or defects
• Congestive heart failure—when failing heart leads to fluid congestion
a) in lungs (pulmonary edema), b) in body (edema)
– Heart failure almost always progresses to congestive heart failure
Cardiomyopathy: 2 Types
• Dilated Cardiomyopathy
(DCM)
• Hypertrophic
Cardiomyopathy (HCM)
Canine Dilated Cardiomyopathy
• One of the most commonly acquired heart diseases in dogs
– Boxers, Dobermans
• Seen in older large/giant breeds
• Heart chambers dilate because heart wall becomes thin,
weak, flabby
• ↓ CO (cardiac output), ↑ blood left in heart after systole
Canine Dilated Cardiomyopathy
• Signs
– Giant/large breed dogs; older
(4-10 y)
– Exercise intolerance
– R sided failure
• Ascites/abdominal distension
• Hepatomegaly
• Wt loss
– L sided failure
• Coughing
• Pulmonary edema
• Syncope
Canine DCM
• PE
– Weakness, depression
– Hypokinetic femoral pulse from low CO
– Pulse deficits
– Jugular pulses
– HR – fast 150-200+
Canine Dilated Cardiomyopathy
• Dx
– X-rays may show dilated heart
– Ultrasonography will show dilated heart chambers
– ECG
• widened/large QRS and P waves
• rhythm disturbances
• Rx—no cure
– Diuretics to ↓ fluid buildup
• Furosemide
– Digoxin
• ↑strength of contraction (↑CO)
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Nitroglycerin x 24-48 hrs
OXYGEN!!!
Vasodilators (enalopril,etc)
Pimobendan - + inotrope, increases survival
• Client info
Canine DCM
– Fatal disease (6mo to 2 y) – SUDDEN DEATH
– More prevalent in large breeds
– Diet – decrease Na intake
– Minimal exercise – let patient be guide
http://www.vetspecialistsofrochester.com/Cardiology/Canine_Conditions.aspx
Canine Hypertrophic Cardiomyopathy
Uncommon in dogs
L ventricular muscle enlarges, decreasing chamber size of L ventricle
Heritable
• Signs
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Fatigue
Cough
Tachypnea
Syncope
± cardiac murmurs
Sudden death
Some animals will be asymptomatic
Normal
Hypertrophy
• PE
– Systolic heart murmur
– Cardiac gallop rhythm
– LH failure: cough, dyspnea, cyanosis, exercise intolerance
Canine HCM
• Dx
– X-rays may be normal, have La or LV enlargement and/or pulmonary
edema
– Ultrasound shows thickened L vent wall
– EKG: Normal or ST segment and T wave abn
• Rx—none routinely used unless signs of HF
• Client info
– Sudden death and CHF may occur
– Certain breeds more susceptible (G Shep, Rott, Dalm, C Span, Bostons,
Shih Tzu)
Feline Dilated Cardiomyopathy
Prior to late 1980’s, this was frequently seen in cats
Associated with taurine deficiency; addition to cat feed has
greatly reduced incidence
Similar pathology to DCM in dogs
• Signs
– Older, mixed breed (Siamese, Burmese,
Abyssinian)
– Dyspnea, tachypnea
– Inactivity
– Anorexia
– Acute lameness/paralysis (rear legs)
– Pain/lack of circulation in affected
limbs (no pulse due to thromboemboli)
Feline DCM
• PE:
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HR variable (fast, normal or slow)
Systolic heart murmur
Gallop rhythm
+/- arrhythmia
Hypothermia
Increased CRT
Tachypnea
Quiet lung sound (if pleural effusion)
Crackles if pulmonary edema
Hypokinetic femoral pulses
+/- posterior paresis/paralysis
Feline DCM
• Dx
– Clin signs; ECG; ultrasound
– Taurine levels
– X-rays
Feline Dilated Cardiomyopathy
• Rx
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Oral taurine supplement (250-500 mg/d)
Furosemide
Oxygen
Digoxin
Aspirin or heparin – prevent thromboemboli
Vasodilator; ↓vascular resistance
• Hydralazine
• Cutaneous nitroglycerin paste
• Client info
– Most dangerous time is first 2 wks of treatment
– If cat responds to taurine treatment, good Px
– Unresponsive to taurine treatment, poor long-term Px
Feline Hypertrophic Cardiomyopathy
Similar to HCM in dogs
L vent hypertrophy is predominant pathology
More common in neutered males
• Signs
– Soft, systolic murmur (grade 2-3/6)
– Gallop rhythm and other arrhythmias
– Acute onset of heart failure or thromboembolism
• Dx
– X-rays—may be normal
– ECG
• ↑P wave duration
• ↑QRS width
• Sinus tachycardia
– Ultrasound
• ↑L vent wall; dilated L atrium
Feline Hypertrophic Cardiomyopathy
• Rx
– Diuretics to decrease fluid load on heart
• Furosemide
– Beta blocker to decrease sinus heart rate
• Propanolol
– Calcium channel blocker to reduce blood pressure
• Diltiazem
• Client info
– Affected cats may experience heart failure, arterial embolism,
sudden death
– Cats with HR <200 bpm have better Px than >200 bpm
– Median survival time ~2 y
Thromboembolism
Common in myocardial disease in cats (10-20% of HCM)
Forms in L side of heart
Lodge at femoral trifurcation
Thromboembolism
• Signs
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Acute onset of rear leg pain/paresis
Cold, bluish foot pads
Lack of femoral pulse
Hx of myocardial disease
• Dx
– Clinical signs
– Angiography (if available)
• Rx
– Dissolve clot
• TPA (Activase [Genentech])
• Heparin
– Aspirin for prophylaxis
• Aspirin is slowly metabolized in cats; must be monitored
• Client info
– Painful, cold, or paralyzed rear legs in cats is an emergency
– Px is guarded to poor
– Surgical removal of thrombus is difficult/expensive
Fetal Heart
Right
atrium
Vena cava
Congenital Heart Disorders
• Patent Ductus Arteriosus (PDA)—failure of ductus arteriosus
to close after birth
– Blood shunts from systemic circulation to pulmonary artery
– Normally, prostagladins are released at birth to cause
ductus arteriosus to close
Ductus arteriosus
To lungs
To lungs
To lungs
PDA
• Clinical signs
– Usually female
– Predisposed breeds: chi, collie, maltese, poodle, poms, E Spring, kees,
bichons frises, Shetlands
– Presence of a loud heart murmur over L thorax
– Some puppies are asymptomatic
• Dx
– ECG
• L vent dilation
– X-ray
• L atrial and L vent enlargement
• Rx—surgical correction
• Client info
– Px is excellent following surgery
– 64% of PDA will die within 1 y without surgery
– Dog should not be used for breeding
Congenital Disorder:
Atrial Septal Defects
An abnormal opening in the atrial wall
Foramen ovale—a hole in fetal atrial septum to allow oxygenated blood from the
placenta to by-pass lungs (like ductus arteriosus)
-should seal at birth
• Signs
– Soft, systolic murmur
– CHF before 8 wk old
C
After birth, blood is shunted
from L to R atria (high press
to low)
Atrial Septal Defect
Congenital Disorder:
Ventricular Septal Defects
An abnormal opening in the ventricular wall
• Signs
– Harsh, holosystolic murmur, R sternal border
– CHF before 8 wk old
• Rx (ASD, VSD)
– open heart surgery
unusual in animals
– Management of CHF
• Client info (ASD, VSD)
– Most will develop CHF
C
Congenital Disorder:
Tetralogy of Fallot
Polygenic malformation of heart (4 abnormalities)
1.
Pulmonic stenosis
2.
2° R ventricular hypertrophy
3.
Ventricular septal defect
4.
Overriding aorta
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Breeds (Keeshond, E bulldog, cat)
Signs
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Failure to grow
Cyanosis
Exercise intolerance
Weakness
Seizures
Syncope, sudden death
Dx
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X-ray—normal size heart
ECG
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R vent hypertrophy
R outflow obstruction
Tetralogy of Fallot
• Rx
– Surgical procedures can improve condition (cardiology
specialty practice)
– Medical treatment includes phlebotomy to keep PCV
between 62-68%
• Client info
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Genetic disease; don’t breed
Sudden death is common; may live for years
CHF is rare
Limit stress/exercise
Tranquilizers/sedatives may have adverse effects
Regular phlebotomies will be required
Acquired Valvular Diseases
• Mitral Valve Insufficiency (most common acquired heart disease in dogs
(progressive); rare in cats)
– Caused by proliferation of fibroblastic tissue within valve leaflets causing
thickening of valvular free edges, causing valves to roll up
– Thickened leaflets fail to close sufficiently during systole → regurgitation into L
atrium → CHF
– A main cause is periodontal disease → endocarditis from bacteria in dental
tartar
Upper leaflet normal
Mitral valves
What are white bands?
Lower leaflet thickened
Mitral Valve Insufficiency
• Signs (L CHF)
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Small breed dog >10 y
Cough: deep, productive; worse at night or with exercise
Dyspnea, tachypnea
Decreased appetite
Systolic murmur, L apex
► Dx
X-ray
► Pulmonary edema may be
present; cotton-like alveolar
disease
► L atrial, vent enlargment
(Elevation of trachea, loss of
cardiac waist)
Mitral Valve Insufficiency
• Rx—there is no cure; goal is to improve quality of life
– Diuretics—furosemide to reduce fluid volume of heart
– Digoxin—to increase efficiency of heart and ↓HR
• Client info
– MVI is a progressive disease; periodic
evaluation/readjustment of Rx
– No cure
– Low salt diet helps prevent fluid accumulation
– Eventually medication will not control the condition
Mitral
valve
(L A-V)
Tricuspid Insufficiency
• Same disease as Mitral Valve Insufficiency except R
sided heart failure results instead of L sided failure
• Signs (R CHF)
– Pleural effusion (fluid in pleural cavity not lung tissue)
– Abdominal distension
– Hepatomegaly
• Rx—same as MVI
Tricuspid
valve
(R A-V)
– Abdominocentesis may be required periodically
Cardiac Arrhythmias
Abnormal heart rate or rhythm or rhythm arising from abnormal
location
Abnormal rhythm result from either:
1. abnormal impulse formation (ectopic beats)
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Ischemia (↓ blood supply)
Hypocalcemia
Cardiomyopathy
Hypercalcemia
Excess catecholamines (↑ adrenalin)
2. abnormal impulse conduction
Sinus arrhythmia
• Normal in dogs; not in cats
– P wave for each QRS
– Irregular ventricular rhythm
P waves
Atrial Fibrillation
No organized atrial contraction
Easier to occur in larger heart, so more of a problem in lg breed dogs
• Signs
– Weakness, syncope
– Collapse
– Rapid, irregular HR
• Dx
– Auscultation
• rapid, irregular HR
– ECG
• No P waves
• Rapid, irregular HR
Many ectopic foci
activating small
areas of atrium
Only ectopic foci close
to AV node are able to
cause impulse to travel
to ventricle
Ventricles are activated
at a very fast rate and at
irregular intervals
Atrial Fibrillation
• Rx (aim is to slow HR; it will not correct fibrillation)
– Digitalis (digoxin) to slow HR
– Ca++ channel blockers (diltiazem HCl) to slow AV node
conduction
• Client info
– Rx will not cure atrial fibrillation
– Concurrent heart disease will progress even with treatment
– CHF will occur eventually
Ventricular Tachycardia
Rapid HR reduces vent filling time, and, therefore decreases CO
If untreated, may lead to vent fibrillation (cardiac arrest), a life-threatening situation
• Causes:
– Cardiomyopathy, CHF, endocarditis, neoplasia
– Electrolyte or acid/base imbalance
• Signs
– Weakness, collapse, syncope with rapid HR
– Sudden death not uncommon
– CHF
Ventricular Tachycardia
Normal beats?
• Dx
– Auscultation: rapid, irregular HR
– ECG: widened, bizarre QRS complexes of vent origin (PVC’s)
• V fib: no QRS complexes
• Rx
– Procainamide and Tocainide decrease myocardial excitability
– Lidocaine decreases automaticity of heart muscle
– For v fib, cardiac defibrillation
• Px—Guarded unless underlying cause can be corrected
Sinus bradycardia
Def: normal P, QRS complexes; HR <70 bpm
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May be symptom of disease:
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↑ Intracranial pressure
Hypothyroidism
Hypothermia
Hyperkalemia
Hypoglycemia
Also seen in athletic, well-conditioned dogs
Sinus bradycardia
• Signs
– Episodic weakness, syncope, collapse
• Dx
– Auscultation: slow HR
– ECG: slow HR; normal P, QRS complexes
• Rx
– Treat underlying disease
– Atropine increases HR
– Placement of artificial pacemaker
• Client info
– May be normal in athletic dog
– Correction of underlying problem may correct bradycardia
– Most dogs can live normal life with this condition
Heartworms (Dirofilaria immitis)
• World-wide distribution
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With 150 mi of Gulf and Atlantic coasts and Mississippi River
Males dogs infected more than females (4:1)
Outside dogs more likely to be infected than indoor dogs
Rare in cats
Heartworm Cases
Heartworms - canine
• Life cycle (Adult → L1 (microfilaria), L2,
L3, L4, L5 [small adult]
– Mosquito bites infected dog, picks up
microfilaria (L1)
• Microfilaria may live up to 2 y in dog
• May be passed transplacentally (will
not develop into adult)
– Microfilaria mature in mosquito to L3
stage (2-3 wk)
• L3 is capable of infecting new dog
– L3 migrates thru soft tissue to heart
• 5-7 mo then becomes L5 (small adult)
– Adults breed and produce L1
– Adults can live in heart for 5-7 years
Canine
Heartworms
Canine Heartworms
• Disease severity
– # adult worms
– Inflammation of endothelium
– R-sided heart failure
• Dx
– Knott’s test—filter technique to
see microfilaria in blood
– Antigen tests detect antigen of
female heartworms
– Antibody tests detect antibodies
dog has produced against larvae;
positive test confirms dog has
been exposed to larvae
Canine
Heartworms
HW Life Cycle
Heartworms
• Signs
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Usually asymptomatic; diagnoses on routine screening
Exercise intolerance
Coughing, dyspnea
R-sided heart failure
• Rx—pretreatment lab workup (CBC, Chem Panel)
– Melarsomine (Immiticide; Merial)—kills adult worms
– Ivermectin—kills microfilaria and migrating worms (L3, L4)
– +/- Doxycycline
– Prevention—many products
– Diethylcarbamazine (daily)
– Ivermectin (monthly)
– Milbemycin (monthly)
Feline Heartworms
• Prevalence – 1997 necropsy survey in SE Texas
– 10% of shelter cats had adult HW
– Greater infection rate than FeLV or FIV
Feline Heartworms
• Epidemiology
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Female mosquito feeds on infected dog; picks up mf
Become L1 to L3 in mosquito
Deposited on skin of cat or dog in saliva
L3 enter thru bite, molt to L4, migrate through tissues for 2 months
Final molt to immature adult (previously L5); enter peripheral vein
Immature worms carried to heart – 75-90 days PI
By day 100 – worms 2 inches long
Matures to adult over 2-3 months
Most juvenile worms die shortly after arriving in pulmonary arteries
Initiates an inflammatory reaction
A few worms live 2-4 years in small percentage of cats
Feline Heartworms- Heartworm Asocciated
Respiratory Disease (HARD)
• 3 stages
– 1st
• Acute inflammatory reaction to presence and death of
worms
• Coughing, dyspnea
• Intermittent vomiting
• 28% asymptomatic
• X-rays – inflammatory infiltrates around R caudal lobar
artery
• Similar to allergic bronchitis or asthma
• Responds to steroids
Feline HARD
• 2nd stage
– Adult HW (if survives) suppresses immune system =>
decreased signs
– Worm dies – no more immune suppression
– Intense inflammatory reaction occurs
– Thromboembolism => acute lung injury and sudden death
• 3rd stage
– If cat lives => permanent injury and chronic resp disease
Feline Heartworms
• Diagnosis
– Filtration for mf useless – usually single sex infections (1-2
worms only)
– X-rays as above – 55% have radiographic signs
– US – 70-100% accurate
– Serology
• Ag tests – do not detect early or male only infections
– Negative result does not r/o HW dz
• Ab test – confirms recent infection with L4 or older but not disease
• Ag test in process of being added to FeLV/FIV test.
Feline Heartworm Testing
Feline Heartworm X-rays
Feline Heartworms
• Rx—
– Acute respiratory distress
• Steroids (Dex SP 1-2 mg/kg IM/IV, PredSS 50-100 mg/kg/cat IV
• Bronchodilator
• Supportive – IV fluids, etc
– If not demonstrating clinical signs, supportive care until
heartworm dies
• Prednisolone to reduce pulmonary effects
– +/- doxycycline
Feline Heartworms
• Prevention
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Safe for all cats because mf infection rare or minimal
Heartgard® for Cats (Ivermectin, orally) from Merial
Interceptor® (Milbemycin oxime, orally) from Novartis
Revolution® (Selemectin, topically) from Pfizer
Advantage Multi™ for Cats (Moxidectin / imidacloprid,
topically) from Bayer
Respiratory Diseases
Upper Respiratory Diseases
Upper Respiratory Tract is any resp structure above the trachea
• Rhinitis—inflammation/infection of nasal passages
Usually occurs with other resp diseases
– Signs
• Nasal discharge; crusty nares
• Pawing at nose
• Staphylococcus spp
– Rx
• Clean nares
• Antibiotics if necessary
Upper Respiratory Diseases
• Sinusitis
– Usually due to abscess of 4th premolar (Carnassial tooth)
• Largest tooth; roots extend into frontal/maxillary sinus
– Signs
• Swelling under eye on infected side
• Unilateral nasal discharge
– Rx
• Remove infected tooth
• Antibiotics
• Flush fistula with iodine solution
Upper Respiratory Diseases
• Tonsillitis (Tonsils provide lymphoid protection to lower resp tract)
– Signs
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Anorexia
Increased salivation
Pain on opening mouth
It is more common in small dog breeds
– Dx
• Visualized inflamed, swollen tonsils
• Tonsils may be coated with mucus/pus
– Sx
• Antibiotics
• Surgical removal of chronic cases
Tonsillitis
Upper Respiratory Diseases
• Laryngitis
Most common cause is excessive barking
**Rabies can also change vocal quality
• Signs
– Loss of voice or alteration of voice
– Increased mucus production in back of throat
• Rx
– Restrict barking
– Anti-inflammatory medication (glucocorticoids)
• Client info
– Most Upper Respiratory Infections are self-limiting
Lower Respiratory Diseases
Lower Respiratory Tract includes trachea, bronchi, lungs, pleural cavity
• Infectious Canine Tracheobronchitis (Kennel Cough)
– Causes (a collection of several causative agents including viruses,
bacteria, mycoplasmas, fungi, parasites
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Canine parainfluenza virus
Canine adenovirus
Canine herpesvirus
Reovirus
Bordetella bronchiseptica
mycoplasma
– Signs
• Hx of exposure to animals at a kennel, hospital, groomer, show
• Dry hacking cough in an otherwise healthy animal
– Rx—antibiotics, glucocorticoids, antitussives
– Client info
• Self-limiting (2-3 wks); Rx is to make animal/owner more comfortable
• Vaccinate 2-3 wk before chance of exposure
Lower Respiratory Diseases
• Collapsing trachea
Failure of proper development of tracheal rings
– Signs
• Cough, esp during excitement or exercise
– Dx
• Goose-like honk on tracheal palpation
• r/o other causes of coughing
– Rx
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Acepromazine to calm excitement
Antitussives (Hycodan, Butorphanol)
Glucocorticoids
Bronchial dilators
Prosthetics have been surgically implanted, but complications have occurred
– Client info
• Wt reduction
• Use shoulder harness rather than neck collar
Lower Respiratory Diseases
• Feline Bordetella Infection
Bordetella bronchiseptica grow in ciliated respiratory mucosa; release toxins
– Signs (look like respiratory viral infections)
• Fever
• Sneezing, nasal discharge, coughing, rales
• Submandibular lymphadenopathy
– Rx (usually self-limiting)
• Antibiotics (oral tetracycline or doxycycline)
– Prevention
• Eliminate stress
• Good hygiene, good nutrition
• Vaccination
– Client info
• Looks like resp infections caused by feline herpes and calicivirus
• Usually self-limiting
• Vaccination effective
Lower Respiratory Diseases
• Feline asthma (bronchoconstriction, inflamed/hyperreactive airways)
– Signs
• Coughing, wheezing
• Labored breathing
– Dx
• Clinical signs
• X-rays show “doughnuts” typical of airway inflammation
– Rx
• Long-term corticosteroids (prednisone, DepoMedrol)
• Bronchodilators (terbutaline [Brethine], cyproheptadine)
– Client info
• Prognosis is variable
– If allergens can be determined and exposure limited, most cats do well
– A cure is not usually possible
Feline Asthma
• Same cat
– Top—normal
– Bottom—asthma
Airways more prominent because of
inflammation and mucus buildup
Doughnuts (end-on view) and
tramways (lateral view) of airways
Feline Viral Resp Infections
• 2 viruses responsible for most feline resp diseases
– Feline Viral Rhinotracheitis (FVR; Feline Herpesvirus)
– Feline Calicivirus (FCV) Caliciviridae family
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Highly contagious
High mobidity
Low mortality
Most severe in kittens
Feline Viral Rhinotracheitis
• Signs
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Acute onset of sneezing
Conjunctivitis, severe rhinitis
Fever, depression, anorexia
Ulcerated hard palate, excess salivation
Corneal ulcers
• Rx
– Supportive Rx
• IV fluids, broad spectrum antibiotics, decongestants
• Nursing care: clean nose, eyes; force feed food; decrease stress
• Antiviral therapy
• Prevention
– Vaccination
• Client info
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FVR highly contagious; can transmit via clothing, hands, etc; only cats
Warming food may improve palatability
Vaccinated cats may show mild symptoms
Disinfectants kill herpesvirus type I virus
Feline Calicivirus
• Signs
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Fever
Serous ocular/nasal discharge; mild conjunctivitis
Oral ulcers, salivation
Pneumonia
Diarrhea
• Rx
– Supportive care
– Antibiotics
– Force feed disinfect using bleach
• Prevention
– Vaccination
• Client info
– Highly contagious
– Signs last 5-7 d
– Force-feeding may be necessary (if cats can’t smell, they won’t eat)
What do you see? or What do you not see?
Pleural
Effusion
Dx—x-ray
Fluid in thorax
• Types of fluid
Causes
– Transudate
R-sided CHF, FIP
plasma-like fluid; straw colored
– Blood
– Chyle
trauma, neoplasia
neoplasia, pancreatitis, trauma
lymphatic fluid from intestine; high fat content
infection, parasites
--Empyema
Infection, foreign body, trauma
pus in thorax
All types of fluid cause same signs
– dyspnea
– may show cough, fever, pleural pain
Pleural Effusion
• Thoracentesis
– Clip hair, scrub skin, block with local anesthetic
• Most dependent space (7th-8th intercostal space)
– Aspirate using 3 way valve
– Remove as much fluid as possible
• Do not create pheumothorax
– Analyze aspirate
• Rx—depends on pathology causing effusion
• Client info
– Owner may need to continue pleural drainage
– Unless 1° is treated, effusion will return
– Rx can be long and expensive
Fungi
Fungal Diseases
Usually result from inhalation of fungal spores or wound contamination
Fungi release enzymes/toxins that damage host’s cells
Endemic along east coast, Great Lakes, river valleys of the Miss, Ohio, St
Lawrence
• Commonly seen fungal diseases of animals
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Blastomycosis
Coccidioidomycosis
Histoplasmosis
Aspergillosis
Blastomycosis (Blastomyces dermatitides)
• Signs (non specific)
– Anorexia, depression, wt loss
– Fever, cough, dyspnea
– Enlarged LN
• Dx
– X-rays—diffuse, nodular interstitial lung pattern (x-ray)
– Serology testing is available
– Most cases are diagnosed in the fall.
• Rx
– Amphotericin B
• Client info
– Blastomycosis usually not zoonotic disease, however, use caution with
animals with draining wounds
– Owners share same environment and are likely to be exposed
– Relapses are common
– Rx is expensive
Coccidioidomycosis (Coccidioides immitis)
• Signs
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Mild, non-productive cough
Low-grade fever, anorexia, wt loss
Weakness, depression
Lameness, pain is bone involvement
LN enlargement
• Dx
– Parenchymal changes on x-ray
– Serology
• Rx
radius-ulna
– Ketoconozole
– Itraconazole
• Client info
– Usually not zoonotic disease, however, use caution with animals with draining
wounds
– Response to Rx is good, but recurrence is common
– Rx is expensive
Histoplasmosis (Histoplasma capsulatum)
• Organism which grows in bird manure, bat dropings or organically
enriched soil.
• Signs
– Feline (pulmonary signs)
• Wt loss, anorexia
• Fever, pale mm, swollen LN
– Canine (GI signs)
• Wt loss, diarrhea, low-grade fever
• Dyspnea, cough, pale mm
• Dz
– CBC: anemia
– X-ray: diffuse pulmonary interstitial pattern
• Rx
– Ketoconazole
– Itraconazole
• Client info
– Px fair to good for pulmonary form; guarded to grave for systemic form
Cryptococcosis (Cryptococcus neoformans)
A yeast-like fungus found in soil contaminated with pigeon and other bird droppings.
Inhalation major route of infection. Immunocompromised animal more susceptible
than normal animal
• Signs
– Feline
• Lesions in nasal and sinus cavities; chronic nasal discharge
• enlarged LN, wt loss, anorexia, lwo-grade fever
– Canine
• Dx
• Usually CNS lesions (vestibular dysfunction)
– Cytology of aspirates, impression smears
– Antigen test available
• Rx
– Amphotericin B
– Ketoconozole
– Itraconazole
• Px
– Fair to good unless CNS involvement
– No known health hazard to humans
Aspergillosis (Aspergillus fumigatus)
Inhalation major route of infection; nasal cavity is main location of lesions
• Signs
– Feline (uncommon)
• May be immunocompromised (FeLV)
• Lethargy, fever, wt loss, anorexia
– Canine (localized)
• Young to middle age
• Chronic nasal discharge, sneezing, loud breathing (like snoring)
– Canine (generalized infection)
• Primarily seen in G Shep
• Wt loss, anorexia
• fever, lameness, paresis/paralysis
• Dx
– X-ray—loss of nasal turbinates
– endoscopy:--yellow-green to black fungal plaques on nasal mucosa
Rx—topical clotrimazole
•
• Client info
– Localized dis—poor Px; Generalized dis—grave Px; not zoonotic
Pulmonary Neoplasms
Tumors in lungs are usually metastatic, although primary lung tumors do
occur
• Signs
– Primary neoplasia
• Cough, exercise intolerance
• Wt loss, poor condition
• Dysphagia, vomiting, anorexia
– Metastatic neoplasia
• Evidence of primary tumor at other location
• Same signs as above for Primary neoplasia
Pulmonary Neoplasms
• Dx
– Chest X-rays—mass occupying lesions; can be mistaken for
abscess, parasitic dis, fungal infect, bact infect
– Biopsy—provides
definitive diagnosis
Pulmonary Neoplasms
Same dog as x-ray
• Rx—surgical removal is TOC
– Lobectomy for solitary tumor
• Chemotherapy (may reduce tumor size, may not increasse survival
time
• Client Info
– Px is guarded to grave
– By the time these tumors are diagnosed, they are usually
in advanced stages
– Chemotherapy may reduce clinical symptoms