Respiratory Material Flashcards
What lesions are associated with infective endocarditis that contain platelets, fibrin, microorganisms, inflammatory cells and bacteria?
Vegetative lesions
What is the cause of acute regurgitation in infective endocarditis patients?
Structural valvular changes
What are the most common valves affected with infective endocarditis?
Mitral and aortic
Describe an aortic and mitral murmur.
Aortic: left basilar diastolic + bounding pulses
Mitral: left apical systolic
What is required for the development of IE?
Bacteremia
What are three clinical syndromes resulting from IE?
Immune-mediated disease, CHF/arrhythmias and THromboembolic disease
What are your most common breeds IE is seen in?
GSD, goldens, Labs
What is the most common presenting complaint in a dog with IE?
Owner complains about lameness- this can be due to the immune-mediated complexes that are deposited in the joints (polyarthritis)
What important protein is lost in the urine and can lead to thromboembolism?
Antithrombin III is lost in urine. This protein is needed for clot breakdown- without this protein there will be thrombi formed all over the body without “regulation”
T/F: You always collect blood cultures before antibiotic therapy.
TRUE
What is a common finding on thoracic rads with IE?
L-sided CHF
What are the five common causative agents of IE?
Staph intermedius, staph aureus, strep canis, e coli, bartonella
What is the mainstay of IE therapy?
Long-term bactericidal antibiotics
T/F: dogs with IE have grave prognosis and permanent damage to the valves despite infection resolution.
TRUE
A patient with this disease should be receiving periprocedural antibiotics to prevent formation of IE.
Congenital heart disease patients- especially subaortic stenosis
Myocardial inflammation in the absence of ischemia –> myocyte damage and cardiac dysfunction is also known as?
myocarditis
What CS are commonly seen with myocarditis patients?
Fever, lethargy, hyporexia, resp signs, syncope, muscle pain and diarrhea
What arrhythmias are commonly seen in patients with myocarditis?
VPC
What is often leaked from damaged/necrotic cardiomyocytes into circulation that can be used to diagnose a patient with myocarditis?
Cardiac troponin I
What is the most common cause of myocarditis in Texas?
Chagas disease
T/F: Systemic hypertension in dogs/cats is a primary disease
FALSE- occurs secondary to other conditions
What is the basic pathophysiology of systemic hypertension?
Arterial/arteriolar walls diseased and vessel lumen is narrowed –> reduced blood flow to tissues/hemorrhage from vessel fragility
T/F: Cardiac disease can cause hypertension in SA patients
FALSE- SH can often lead to cardiac disease
What are the four target organs of damage?
Renal, Ophthalmic, neurologic and cardiovascular
What type of renal damage is seen with SH?
Glomerular/tubulointerstitial (ischemia, necrosis and atrophy)
What is the drug of choice used to treat hypertension in cats?
Amlodipine: inhibits Ca influx across vascular smooth muscle cells
What are some common side effects of ophthalmic damage from SH?
Vision loss, retinal detachment, retinal hemorrhage
What are common cardiac damages seen alongside SH in pets?
LV concentric hypertrophy, diastolic dysfunction, mitral regurgitation
What is the leading cause of SH in dogs and cats?
Renal disease
What is a common drug used in dogs that can cause SH as an adverse affect?
PPA
What happens if the BP cuff you’re using is too small/big?
Too big= false low; Too small=false high
If there is TOD and BP > 180 what do you do?
Start tx of hypertension in addition to TOD tx
What do you do if you patient has >180 mmHg BP?
Start hypertension tx
What if you suspect your patient to have SH and upon evaluation they have no TOD and <180 mmHg BP, how do you respond?
Reassess within one week
What is the drug of choice in dogs for SH?
Angiotensin-converting enzyme inhibitor: indirect vasodilator blocking formation of angiotensin II
How many consecutive readings for BP should you get in hypertensive patients?
3 consecutive readings (toss out the first reading)
Where do adult heartworms typically live?
Pulmonary a.
T/F: molting of dirofilaria immitis is dependent on ambient temperature & wolbachia
TRUE
Where can S5 HW migrate to besides the pulmonary artery?
Main pulmonary artery, right side of heart and vena cavae (heavy infections)
What do the worms cause in the artery?
Induce inflammation, endothelial damage, myointimal proliferation, disruption of vascular integrity, fibrosis, and pulmonary hypertension
What do dead worms induce?
Thrombosis and more inflammation
What is it called when you have mechanical obstruction (by worms) of blood flow in the R. side of the heart and vena cavae?
Caval syndrome
What are some CS seen with HWD dogs?
Exercise intolerance, wt loss, lethargy, cough, abdominal distension, syncope, hematuria
Which side of the heart is commonly affected in HWD?
R-sided CHF- tricuspid regurgitation (right apical systolic murmur)
What tests are commonly run to assess microfilaria after you have a positive antigen test for HWD?
Modified knott or filter test
What will you see on thoracic rads in a dog with HWD?
Dilation of any or all pulmonary a. and R-sided enlargement. Infiltrates are commonly seen.
What is the test of choice if there is an arrhythmia in a HWD patient?
Electrocardiography
What are the four tx options for HWD dog?
- Macrocyclic lactone preventative (ivermecitn, milbemycin oxime)
- Doxycycline (reduces/eliminates Wolbachia)
- Exercise restriction (IMPORTANT)
- Adulticide therapy with melarsomine dihydrochloride
Why should milbemycin be avoided in microfilaricide positive dogs?
This can cause quick death of baby worms resulting in severe anaphylaxis shock
T/F: Cats are an unnatural host for Dirofilaria immitis which is why they are quite resistant to the infection
TRUE
What is the common reason we use HW preventatives in our feline patients since the pevalance of infection is so low?
We are trying to prevent our feline friends from getting HARD
Inflammatory & proliferative disease of the pulmonary arteries, bronchioles and pulmonary parenchyma in cats WITHOUT mature infections is known as what?
Heartworm-associated respiratory disease (HARD)
What cell type contributes to the profound inflammatory reaction to S5 in cats?
Pulmonary intravascular macrophages (PIMs)
What do the symptoms of HARD in feline patients look similar to?
Asthma
What are acute respiratory signs in felines a result from in HW infection?
Dead worm embolization
Current dx tests detect Ag produced where in the parasite?
Reproductive tract of adult female (insensitive for detecting HWI in felines because they typically only have 1 worm and this test usually picks it up with >3 worms present)
When does Ab-positive status occur in HWD patients?
Larvae have developed to stage L4
Why is microfilarial testing not typically performed in cats?
often amicrofilaremic or low microfilaria numbers
What defines pulmonary hypertension? (systolic, mean and diastolic)
Systolic: > 30 mmHg
Mean: > 20 mmHg
Diastolic: >15 mmHg
What are the three mechanisms of PH?
Increased CO, increased pulmonary vascular resistance and increased pulmonary venous pressure
What are the five classifications of PH?
- PH due to pulmonary vascular dz
- PH due to L-sided heart dz
- PH due to chronic pulmonary dz/hypoxia
- PH due to thrombotic/embolic dz
- Miscellaneous
What are some PE findings with PE patients?
Dyspnea/tachypnea, abnormal lung sounds, cyanosis, murmur from tricuspid regurgitation (might have systemic hypotension)
What is the gold standard test for PH patients?
Echocardiography
What are some common findings with PH patientson thoracic radiographs?
Pulmonary infiltrates with severe pulmonary hypertension
- dorsal deviation of trachea, sternal contact increased, dilated main pulmonary artery
T/F: If you have concentric hypertrophy of RV and the pulmonic valve is normal- you can infer that there is pulmonary hypertension.
TRUE
What is seen on Echo due to the increased RV pressure preventing LV to fill up normally
Diastolic flattening of ventricular septum
What is the drug of choice for tx pulmonary arterial hypertension?
Slidenafil: phosphodiesterase V inhibitor
T/F: Supplemental O2 can be used to dilate pulmonary arteries
TRUE
If PH patient hasn’t improved on slidenafil on its own, what drug can you use?
Pimobendan
___ is the obstruction of a pulmonary artery by a thrombus that originated in systemic venous circulation.
PTE
What are the three componenets to a thrombus formation? (Vrichow’s triad)
- Hypercoaguability
- Endothelial injury
- Blood stasis
What are two mechanisms of gas-exchange impairment seen with PTE patients?
Ventiation-perfusion mismatch and diffusion impairment
T/F: Onset of signs with PTE patients is acute.
TRUE
What product of clot breakdown can be used as a dx test for PTE?
D-dimers
T/F: Thoracic radiographs with a PTE patient may appear completely normal.
TRUE
What radiographic finding would be fairly specific for a PTE patient?
Hypovascular area/lobe
What arterial blood gas finding may be abnormal with a PTE patient?
Hypoxic, hypocapnic and increased alveolar-arterial gradient
T/F: normal D-dimers in a patient with acute respiratory signs rules PTE in?
FALSE- rules out
What is an initial/acute tx for PTE patients?
Anticoagulant therapy with unfractionated heparin (less chance of bleeding complication) or low molecular weight heparin (more targeted in coag cascade, $$)
What are two categories of drugs used for PTE patients?
Anticoagulant and antiplatelet
What is the most common pleural space disease that you will see?
Pleural effusion- abnormal accumulation of fluid in pleural space
What kind of breathing pattern is seen in patients with pleural effusion?
Restrictive breathing pattern (shallow and rapid)- increased inspiratory effort and rate
What are the three effusion categories?
Transudate, modified transudate and exudate
Which type of effusion would a patient with protein-losing enteropathy have?
Transudate- low protein and low cells
This patient will have a colloid oncotic pressure problem
What is the most common exudate found in patients with pleural effusion and what is an example of a disease in this category?
Modified transudate
CHF
What category of pleural effusion would pyothorax fall under?
Exudate- high protein and high cells (SEPTIC patients)
What would you hear when auscultating the lungs of a patient with pleural effusion?
Muffled or absent lung sounds- this is because there is a layer of water between the lungs and your stethoscope, so you will not be able to hear the sound waves as readily as a normal patient where it is just a tissue/muscle interface between
What dx method is commonly used to quickly confirm the dx of pleural effusion?
Thoracic FAST- this is important because it causes minimal stress to the patient
When would you consider placing a pleural port in a patient with pleural effusion.
When they have an underlying disease that cannot be resolved
What is one of the few curable respiratory diseases that was discussed?
Pyothorax- must be caught early
Why is it so important to stop the chronic fluid build up in a patient with pleural effusion?
Chronic fluid –> Chronic inflammation –> Fibrosis
What are the three types of pneumothorax and which is most commonly seen?
Traumatic, spontaneous, iatrogenic
Traumatic is most commonly seen
T/F: The skin wound in a patient with pneumothorax can be centimeters away from the site of penetration into the lungs.
TRUE
T/F: Spontaneous pneumothorax patients are often times congenital
TRUE
T/F: You as the doctor can cause pneumothorax while performing thoracocentesis.
TRUE (also seen during IPPV mishaps)
Pneumomediastinum is most commonly caused by what?
Damage from the trachea
What are some CS of a pneumomediastinum patient?
Tachypnea, dyspnea, SubQ emphysema (crunchy skin) and vomiting (CATS)
What is a common routine procedure that can cause pneumomediastinum?
Dental cleanings- flipping the patient constantly and the ETT can damage the trachea and potentially rupture it
What three components are considered to make up the pulmonary parenchyma?
Alveoli, microvasculature and interstitium
What is the primary function of the parenchyma?
Gas exchange
T/F: The rate of transfer of gas through tissue is proportional to the tissue area and the difference in partial pressure of gas and inversely proportional to tissue thickness.
TRUE
What is the MOST COMMON pulmonary parenchymal disease?
Pneumonia (bacterial)
What is the second most common pulmonary parenchymal disease?
Idiopathic pulmonary fibrosis
T/F: Primary pathogens more commonly result in bacterial pneumonia as opposed to opportunistic pneumonia?
FALSE- opposite
What are your common opportunistic pathogens in dogs and cats?
Dogs: E. coli, pasteurella, klebsiella, staph, strep, bordetella (mycoplasma can-uncommon though)
Cats: mycoplasma, pasteurella, bordetella and e. coli
What are the two classifications of bacterial pneumonia?
Community-acquired and hospital acquired pneumonia
What is important to know about hospital-acquired pneumonia agents?
These bugs typically are drug resistant
T/F: Patients with bacterial pneumonia typically have a non-productive cough as the main presenting complaint
FALSE: productive cough
What is the classic rad pattern in a pneumonia patient?
Ventral alveolar pattern
What is the def dx. of bacterial pneumonia?
identification of sepsis from lower airway samples
What is the typical tx for pneumonia patients?
Ab for at least 2 weeks and continue for 1 week post CS resolution
Tx of choice for a dog with HAP pneumonia would be what?
1st generation cephalosporin (B-lactam) + 2nd/3rd generation cephalosporin
T/F: Often times patients with pneumonia are in a lot of discomfort from the productive cough- it is important that you supplement the dog with a cough suppressant.
FALSE- never give a patient with pneumonia a cough suppressant- this is their body’s way of trying to clear the foreign substance
Along with lower respiratory signs, what else is noticed upon evaluation of a patient with mycotic pneumonia?
Lymphadenopathy and weight loss are of concern
What is the most common cause of protozoal pneumonia?
Toxoplasma gondii
What are the two breeds most commonly predisposed to idiopathic pulmonary fibrosis?
West highland terrier and stafforshire bull terrier
What lung sound is often associated with patients who have idiopathic pulmonary fibrosis?
Crackles
What radiographic abnormalities are seen in patients with idiopathic pulmonary fibrosis?
Bronchointerstitial pattern is most common in dogs
T/F: Non-cardiogenic pulmonary edema is typically protein-rich
TRUE
Cardiogenic pulmonary edema is low in protein
What is the most common bronchial disease?
Chronic bronchitis
What is the pathophysiology of chronic bronchitis?
BREAK THE CYCLE- airway collapse occurs secondary to chronic inflammation and coughing –> collapse causes more inflammation and mucous production –> more coughing. Intervene the cycle to MAKE IT STOP
T/F: Patients with chronic bronchitis have a productive cough with a terminal retch
FALSE- non-productive (white foam seen occasionally)
What sounds do you hear on pulmonary auscultation in patients with chronic bronchitis?
Crackles, wheezes and snapping
T/F: Expiratory dyspnea is specific to lower airway problems
TRUE
What lesions will you see on thoracic radiographs in a patient with chronic bronchitis?
Bronchial pattern (donut lesions)
What is the curative tx of chronic bronchitis?
TRICK. NO CURATIVE TX.
This disease is commonly seen in young adult siberian huskies and will have coughing, retching, dyspnea and nasal discharge with an eosinophilia.
Eosinophilic bronchopneumopathy
What is the difference of chronic bronchitis and feline asthma?
Chronic bronchitis: inflammation, mucus and wall thickening
Asthma: inflammation, mucus, wall thickening AND bronchospasm
What are the primary effector cells in allergic asthma in felines?
Eosinophils- release hyper-reactive proteins
What are the most common breeds of cats that have chronic bronchitis?
Siamese cats
T/F: Cats with bronchitis have intermittent coughing and owner may not see the patient coughing everyday
FALSE- daily coughing
Asthma patients have intermittent/episodic signs
What is an important ddx for cats with chronic bronchitis?
HARD (HW associated resp dz)
What defines tracheal collapse?
Dorsoventral flattening of the tracheal rings
Collapse of ___ occurs during inspiration and collapse of ___ occurs during expiration.
Cervical trachea and thoracic trachea
What is a common sound that is heard in dogs with a tracheal collapse?
“Honking”
What is the pathophysiology of tracheal collapse?
Mechanical trauma to tracheal mucosa –> inflammation is a result –> coughing is stimulated –> increased intrathoracic pressure –> tracheal collapse is exacerbated –>inflammation increases –> more coughing SO ON SO FORTH
What area in the body is the area of severe tracheal collapse?
Thoracic inlet
What is the common signalment for a patient with tracheal collapse?
Small breed, chronic honking cough with terminal retch and owner may complain about these episodes when they are picking their dog up
T/F: A cough elicited with tracheal palpation is specific for tracheal collapse
FALSE- suggests tracheal sensitivity
T/F: Normal radiographs rule out tracheal collapse
FALSE- this is a dynamic condition, so you may not have caught it at the right time
What are the three functions of the larynx?
Regulate airflow
Protect trachea from aspiration during swallowing
Control phonation
Which nerve innervates all but 1 of the intrinsic laryngeal muscles?
Caudal laryngeal n.
What is the most common cause of acquired laryngeal paralysis?
Polyneuropathy
What breeds do you commonly see polyneuropathy in?
Rottweilers, dalmatians, and white-coated GSD
What is the most common cause of laryngeal paralysis in labs?
Geriatric-onset
What will exacerbate clinical signs of laryngeal paralysis?
heat, humidity and exercise
What is the name for loud inspiration seen during panting that localizes the problem to the larynx or extrathoracic trachea?
Stridor
What is a fast acting laryngeal swelling drug?
Dexamethasone
What is the most common cause of laryngeal paralysis in cats?
Neoplastic infiltration
What are two other common laryngeal diseases?
Laryngeal collapse and laryngeal masses
What are the two primary defects of brachycephalic airway obstruction?
Stenotic nares and elongated soft palate
What nasal parasite is seen in cats and causes mild chronic inflammation with minimal CS?
Mammomonogamus
What is the dx and tx of Mammomonogamus?
Dx: fecalfloat, rhinoscopic cytology
Tx: fenbendazole
What is the name of the nasal mite that causes sneezing, rhinitis, nasal discharge and facial pruritis in dogs?
Pneumonyssoides
What is the tx for Pneumonyssoides?
Selamectin or milbemycin oxime
What is a problem in the nasopharynx commonly seen in young cats due to chronic inflammation?
Nasal polyps
What CS in dogs is related to nasopharyngeal polyps?
Reverse sneezing
What is a common cause of nasopharyngeal stenosis?
Regurgitation associated with anesthesia
What is the most common cause of fungal rhinitis in cats?
Cryptococcus
What are the CS associated with Cryptococcus?
Sneezing and nasal discharge
What is the most common source of fungal rhinosinusitis in dogs?
Aspergillus fumigatus
What are the CS of a dog with aspergillosis?
Nasal discharge and sneezing
What can be used in tx aspergillosis?
Topical infusion of clotrimazole or enilconazole
What are the most common causes of canine infectious respiratory disease?
Canine parainfluenza virus with bordetella bronchiseptica
T/F: Canine infectious respiratory disease is highly contagious and is transmitted via oronasal exposure from direct contact with secretions or inhalation of aerosolized respiratory droplets
TRUE
What is the incubation period for CIRD?
3-10 days
How long does virus shedding associated with CIRD last?
10 days
T/F: Bordetella can be transmitted through human contact if the human has been exposed to another patient with CIRD
TRUE- fomite and ourselves can transfer this virus- GOOD HYGIENE is important
What are the two main viral causes of feline upper resp tract infec?
Feline herpesvirus and feline calicivirus
T/F: Shedding of herpesvirus in cats increases dramatically in stressful situations
TRUE
What is the definitive dx test for PTE?
CT or angiography
