Exam 5 Flashcards
Lecture 1
Nasal Disease
- Common clinical sigs
- Radiographs and CT interpretation basic abnormal findings
- History and C/S
- Ddx
- Compare and contrast the common biopsy techniques utilized for evaluating nasal disease, nasal swabs, flush, pinch biopsy, and turbinectomy
Clinical signs of nasal disorders
- Nasal discharge
-Sneezing
-Stertor (snoring/snorting-reverse)
-Facial deformity
-Systemic signs of illness
-Central nervous system signs if disease breaches the cribriform plate of calvarium
Nasal Discharge
- Serous: clear, watery, may be normal.
-Associated with viral disease
-May precede mucopurulent discharge - Mucopurulent - what usually causes to be brought to the clinic
-Thick, ropey
-White, yellow, green
-Associated with inflammation
-Viral, bacterial, fungal infections
-Foreign bodies
-Neoplasia
Oral disease - tooth root abscess or oral fistula
Lower airway disease - bronchopneumonia - Hemorrhagic (epistaxis)
-Blood from one of both nostrils
-Can be associated with fungal disease or neoplasia
-Trauma, locally aggressive disease, hypertension, coagulopathies
Diagnostic Approach
- Thorough History
-History of onset
-Duration of disease
-Exposure to travel - Complete PE
-Determine airflow on both sides of nasal cavities with chilled glass slide (or cotton ball test)
-Examine head, oral cavity, eyes, and surrounding soft tissues for symmetry
Fundic exam
FIV
-retinal detachment
-negative menace
-myadrosis
Chronic Nasal discharge - Diagnostic approach
Phase I (noninvasive testing)
-Hx, PE, fundic exam, fecal float, thoracic rads, cytology, tick titers, nasal swab, viral testing (FIV/FELV), MDB, coagulation times, BP, etc.
Phase II (general anesthesia)
-Nasal rads, rhinos copy, dental rads, nasal biopsy with histopath, deep nasal culture, CT
Phase III (referral)
-CT or MRI, frontal sinus exploration
Phase IV (consider referral)
-Repeat phase II in several months using CT or MRI, exploratory rhinotomy with turbinectomy
Diagnostic Tests - Nasal Swab
-Least invasive
-Patient can be awake
-Produces only cytologic sample
-Findings tend to be non-specific
Exeption: cryptococcus in the feline patient
Diagnostic Tests - Nasal Flush
-Minimally invasive
-Patient must be under anesthesia: important to protect airway
-Saline is flushed from internal nares rostrally towards external nares
-Produces only cytologic sample
-findings tend to be non-specific
-Nasal mites occasionally identified
-May flush out foreign body/mites
Diagnostic Tests - Pinch Biopsy
Invasive - coagulation panel and BMBT prior to procedure
-Under general anesthesia
-Small forceps as alligator biopsy cur forces utilized to collect tissue samples
-Produces cytology (touch prep) and histopathology samples
-Minimum 6 samples should be collected
Diagnostic Tests - Turbinectomy
-More invasive
-Under GA
-Performed through a rhinotomy incision (referral)
-Produces cytologic samples (touch prep) and histopathologic samples
Lecture 2
Nasal mycoses in Feline and Canine
Feline Herpes Virus (aka Feline rhinotracheitis)
-Corneal ulceration, dermatitis, abortion, neonatal death
Tx
-Lysine, feline recombinant omega interferon, human alpha 2b interferon
Feline URI (upper respiratory infection)
-Upper respiratory disease complex: highly contagious
-Cats are stressed, immunocompromised or young in age are more susceptible
-Spread through direct contact and fomites
-Mixture of viral and bacterial agents
-Acute and Chronic infections
C/S
-Sneezing, nasal discharge, conjunctivitis, ocular discharge, salivation, anorexia, dehydration
Tx
-Supportive care
-Quickly dehydrate
-Hydration
-Nutrition
No Steroids
-Clear mucus and crusted discharge: vaporizer in bathroom, nasal saline, pediatric nasal decongestants (0.25% phenylephrine or 0.25% oxymetazoline)
-Antibiotics for secondary infection:
First: Doxycycline
Second amoxicillin
Dx
-Based on largely on signalment
-Clinical presentation
-Conjunctival swabs can demonstrate intracytoplasmic inclusion bodies consistent with Chlamydophila felis
-Commercial PCR respiratory panels are useful in some individual cats, and in management of cattery populations
Feline Calici Virus
-Oral ulceration, interstitial pneumonia, polyarthritis
Feline URI - Chlamydophila felis
-Conjunctivitis
Feline URI - Bordetella bronchi septa
-Coughing, pneumonia in young kittens
Feline URI - Mycoplasma spp
-Ubiquitous organism
-Variable relation to disease
Bacterial Rhinitis
-Majority is secondary infection due to inflamed, compromised nasal mucosa
-Very common sequela to nasal disease
-Mycoplasma spp. and Streptococcus equi, subspecies. zooepidemicus may be primary pathogens
-Direct appropriate antibiotic therapy based on cytology, cultures and underlying disease process (e.g., oronasal fistula)
-duration of therapy depends on underlying disease
-typically 7-10 days Tx
-Chronic infections may require 4-6 weeks (should see improvement in 1 week)
Feline Cryptococcus
Cryptococcus neoformans
-Saprophytiuc yeast-like; found in avian excrement
-3-7 micrometer with large polysaccharide capsule
-Occasional systemic signs
-Immunosuppression does NOT predispose
C/S
-Facial swelling/deformity
-Sneezing
-Mucopurulent discharge (=/- hemorrhagic)
-Unilateral or bilateral nasal discharge
-Ulcerative lesion on nasal planum
-Granulomatous lesion from nares
-Submandibular lymphadenopathy
-Ophthalmic lesions (guarded)
-CNS signs (grave)
Dx
-Cytology: FNA of facial lesion, nasal discharge
-Serology: cryptococcal latex agglutination capsular titer. CSF or Serum. Positive titer is diagnostic. Titer may be used to monitor response to therapy
Tx
-Itraconazole: preferred
-Fluconazole
-Ketoconazole
Guidelines
-Tx minimum of two months
-One month beyond resolution or until titer is negative
-Prolonged Tx is some cases (1 year)
Prognosis
-Overall good
-FeLV/FIV positive cats do not respond well
-Magnitude of titer is not prognostic, but can help to monitor response to Tx
-Ocular or CNS lesions = poor prognosis
Feline Cryptococcus
Canine Aspergillosis (common)
Fungal nasal disease in dogs - Aspergillosis
-Aspergillus fumigatus
-Ubiquitous, saprophytic
-Contaminants present in normal animals
-Destruction of nasal turbinates
-Systemic disease rare
C/S
-Mesocephalic to dolichocephalic breeds
-Immunosuppression NOT predisposing factor
-Unilateral mucopurulent discharge with intermittent epistaxis
-May progress to bilateral
-Ulceration/depigmentation
-Nasofacial discomfort common
-Rads: loss of nasal turbinates, unilateral or bilateral, multiple well defined lytic zones within the nasal cavity.
-Increase in soft tissue or fluid density, affects caudal nasal cavity and frontal sinuses. Typically no lysis or deviation of vomer or frontal bones.
Dx
-CT: better at assessing integrity of nasal turbinates and cribriform plate
-Rhinoscopy: turbinate destruction, white or gray mats, plaques or granulomas, Debulk plaques prior to Tx
-Cytology and Histopathology: Branching hyphae
-Fungal culture: usually not necessary. May be normal inhabitant of nasal cavity. Positive culture only supportive
-Serology: Serum antibody titers supportive. False positives occur, can not use to assess response to treatment
Tx
-Topical medications
Clotrimazole 1%
Enilconazole
Procedure:
-Anesthesia, multiple tube placement, infusion for 1 hr,
-C/S resolve within 2 weeks
-Repeat if necessary
-May require sinus trephination
Alternative Tx
-Trephination and placement of tubes into sinuses and nasal cavities . Daily infusion of enilconazole or clotrimazole BID x 7-10d
-Systemic therapy: Indicated if cribriform plate is disrupted or other systemic involvement. Itrazonazole minimum 2-3 mts
CT
Rhinoscopy
Aspergillosis city and history
aspergillosis treatment
Aspergillosis trephination
Aspergillosis Prognosis
-80-90% cure rate with topical Clotrimazole
-60-70% cure rate with systemic therapy
-Debulking plaques improves
Complications
-Meningioencephalitis (often fatal)
-Chronic bacterial rhinitis
Nasal Mites
-Pneumonyssoides caninum
-Sneezing - paroxysmal, violent
-Visualized during rhinos copy and or nasal flushing with saline
Tx
-Milbemycin or Selemectin
Feline Nasopharyngeal polyps
C/S
-Stertor, obstructive breathing pattern, mucopurulent nasal discharge.
-If present in ear canal, can cause head tilt, nystagmus, Horner’s syndrome
-Benign growths that occur in young cats and kittens
-Often attached to base of eustachian tube
- Primary treatment: surgical excision
- short course of antibiotics and prednisone
Nasal Neoplasia
-Older animals >8 years
-Dolicocephalic breeds
-Most tumors malignant (80-90%)
-Locally invasive
-Metastases rare (later stages to LN and lung)
Types
Epithelial (carcinomas)
**Adenocarcinoma (most common in dogs) **
-Squamous cell carcinoma
-Undifferentiated carcinoma
Mesenchymal (sarcomas)
-Chondrosarcoma
-Fibrosarcoma
-Undifferentiated sarcoma
Discrete round cell
-Lymphoma (most common in cats)
-Squamous most common in nasal planum white cats.
-Transmissible general tumor (rare)
-Mast cell tumor (rare)
C/S
-Nasal discharge (unilateral to bilateral)
-Sneezing
-Nasofacial deformities
-Exophthalmia (or exophthalmia)
-Stertor
-Open-mouthed breathing
-Oral deformity
-Dysphagia
-CNS signs
Dx
-Rads: nasal turbinate destruction, soft tissue opacity, bone lysis (frontal vomer), deviation of vomer bone.
-Rhinoscopy with Biopsy
-Blind nasal biopsy
-Rhinotomy, turbinectomy
-Definitive dx requires histopathology
Nasal neoplasia staging and Tx
-Evaluate local lymph nodes
-Thoracic radiographs
Tx
-Radiation therapy = 12-16 months
-Palliative vs. curative = 3-6 mts
Survival factors
-Adenocarcinomas, sarcomas longer
-Undifferentiated and SCC, shorter
-Clinical stage: metastasis to lungs, shorter
-Extensive local invasion, shorter
-Cats tolerate and respond better than dogs
Allergic Rhinitis
-Not well validated in dogs and cats
-hypersensitivity response to airborne allergens
C/S
-Sneezing, serous nasal discharge may progress to mucopurulent
-May worsen with exposure to perfume, smoke, etc
Dx
-History and clinical presentation
-Rads may show increased soft tissue density
Tx
-control allergens
-antihistamines
-corticosteroids
Idiopathic Rhinitis
Feline chronic rhino sinusitis
-Diagnosis of exclusion
-Chronic mucoid or mucopurulent discharge for mts or years
-Sneezing and nasal discharge most consistent signs
-Typically bilateral +/- hemorrhage
-Chronic inflammation leads to turbinate destruction
-Chronic management necessary
-supportive therapy similar to URI
-Nasal/sinus flush may help temporarily
-Antibiotics secondary infections
Canine Lymphoplasmacytic Rhinitis
-Diagnosis of exclusion
-unknown etiology
-No association with CAV-2, parainfluenza, Chlamydophila or Bartonella.
-C/S and cytology similar to feline chronic rhinitis
-Tx: prednisone, antibiotics for secondary infections, higher immunosuppressive doses
-unresponsive in both dogs and cats
Lecture 3
Laryngeal and Pharyngeal disease
Clinical sigs of Laryngeal Disease
-Hallmark signs regardless of etiology are respiratory distress and stridor (high pitch wheezing sound on inspiration due to upper airway obstruction)
Gagging and coughing may be present
-Voice change is indicative of laryngeal disease (dysphonia) but not consistent finding
-Airway obstruction with laryngeal disease causes profound respiratory distress (often acutely)
-Initially patients limit their own physical activity
-Crisis if animal overheats, respiratory effort increases
-Paradoxical motion: soft tissues are pulled into airway during inspiration due to increased negative pressure, which causes the tissue to become more inflamed and edematous
-Respiratory rate is normal to slightly elevated (30-40 bpm) which is abnormal for level of distress
-Inspiration is prolonged and labored
-Expiration is more passive but tissue edema can cause dynamic obstruction during expiration
May be associated with aspiration pneumonia
-Cough
-Lathergy
-Anorexia
-Fever
-Tachypnea
-Abnormal lung sounds
Ddx
-Laryngeal paralysis (large dogs not cats)
-Obstructive neoplasia
-Obstructive laryngitis
-Laryngeal collapse
-Web formation
-Trauma
-Foreign body
-Extraluminal mass
-Acute laryngitis
Pharyngial disease - Clinical signs
Stertor, gagging, coughing, reverse sneezing and dysphagia are more common clinical signs
Ddx
-Brachycephalic airway syndrome
-Elongated soft palate
-Nasopharyngeal polyp
-Foreign body
-Neoplasia
-Abscess
-Granuloma
-Extraluminal mass
-Nasopharyngeal stenosis
Diagnostics
-Rads for identifying radio dense foreign, bony changes, some masses
-Not as useful for dynamic disease: laryngeal paralysis, collapsing airways
-Fluoroscopy: most useful for dynamic disease in which observation of abnormal motion is necessary for diagnosis . Increased exposure to radiation
-Bronchoscope: non-invasive option
-CT/ MRI
-Laryngoscopy/pharungoscopy : useful for direct visual examination of tissues and movement
-Be prepared for more definitive immediate treatment of airway obstruction when scoping
Laryngeal Paralysis Exam
-Ideally performed with flexible laryngoscope, resulting in the least distortion of the laryngeal structures
-Can be performed by direct visualization through oral cavity using a blade laryngoscope
-Short acting injectable agent (e.g., propofol) to produce light plane anesthesia
-Maintain spontaneous deep respirations
-Arytenoid movement is enhanced by administering IV do pram by increasing respiratory rate and effort
-With laryngeal paralysis, one or both sides do not abduct sufficiently with inspiration
-Flow-by-oxygen should be administered during the exam
-Have endotracheal tube available in case your patient has paradoxical motion, laryngeal collapse or recovering
-Don’t do this exam if you are not ready to deal with potential respiratory problems upon recovery
What is a common cause of stertor in the dog and cat?
Dog-brachycephalic syndrome due to elongated soft palate
-Cat-nasopharyngeal polyp
Lecture 4
Laryngeal and pharyngeal disorders
Laryngeal paralysis (LP)
-Failure of the arytenoid cartilages to abduct during inspiration
-Creates an upper airway obstruction
-Abductor muscles are innervated by the right and left Recurrent laryngeal nerves
-Dogs most commonly affected
Causes
-Idiopathic
-Ventral cervical lesions
-Trauma to nerves: direct, inflammation, fibrosis
-Neoplasia
-Anterior thoracic lesion: neoplasia, trauma, port-operative
-Polyneuropathy and Polymyopathy: idiopathic, immune mediated
-Endocrinopathy: hypothyroidism
-Other systemic disorder: toxicity
-Congenital disease
-Myasthenia Gravis
Etiology
-Idiopathic LP is part of generalized neuromuscular or polyneuropathy complex
-Polyneuropathies have been associated with immune-mediated disease, endocrinopathies, other systemic disorders
Congenital LP: Bouvier des Flandres, Siberian Huskies, Bull Terriers
-LP-polyneuropathy complex reported in Dalmations, Rottweilers and Great Pyrenees
Labrador Retrievers
-Damage to the laryngeal nerves of larynx can lead to LP
Laryngeal Paralysis
C/S
-Any age, any breed
-Most common in older, larger-breed dogs
-Hallmark signs of respiratory distress and stridor
-Vocal change may be noted by owner
-Stridorous breathing dog may turn blue
Often acute respiratory crisis requires emergency intervention
-Often present with a history of gagging or coughing, especially when drinking or eating
Diagnosis
-Further workup should be continued to rule out underlying disease
-Evaluate for concurrent pulmonary disease, such as aspiration pneumonia
-Rule out pharyngeal and esophageal dysmotility and megaesophagus
Treatment
-Emergency management of airway obstruction
-Sedation acepromazine, butorphanol or morphine (nothing by mouth because it can get trapped in the trachea)
-Provide cool, oxygen rich environment
-Evaluate for surgical management once stable
**Arytenoid lateralization (“tie-back”) unilateral or bilateral, not if megaesophagus **
-Increase diameter of airflow but not so large to encourage aspiration
Medical management
-When surgery is not an option, it can be attempted
-+/- corticosteroids to reduce inflammation
-Weight management
-Exercise/heat restriction
-Walkin in harness vs. collar
Prognosis
-Fair to good
-Aspiration pneumonia is most common complication
-Guarded prognosis for generalized neuromuscular disease or/and megaesophagus
Brachycephalic Airway Syndrome
C/S
-Vomiting and regurgitation
-Concurrent with GI disease
-Increased intrathoracic pressure created with increased inspiratory effort
Anatomic abnormalities
- Stenotic nares (cats have them too)
- Elongated soft palate
- Hypoplastic trachea (Bulldogs)
- Everted laryngeal saccules: close to the vocal cords, get edematous and affect the airway space
Brachycephalic Airway syndrome
C/S
-Caused by impaired airflow through the upper airways
-Increased intrathoracic pressure
-Loud upper airway noise associated with obstruction: inspiratory phase STERTOR, SNORING
-Cyanosis, syncope
-GI signs of vomiting and regurgitation
Dx
-Based on breed, clinical presentation
-Cervical and thoracic radiographs to evaluate structure, secondary disease
-Visual exam of oropharynx/larynx via scoping
Tx
-Enhance passage or air through limited airways
-Minimize stress factors: limit exercise, cool ambient temperature, weight control
-Surgical correction of abnormalities: excise excessive soft palate and everted laryngeal saccules, correct stenotic nares
-Perform procedures early (particularly stenotic nares) at 3-4 months age before clinical signs develop
Laryngeal Neoplasia
-Uncommon in dogs and cats
-Carcinomas: SCC, undifferentiated, adenocarcinoma
-Lymphoma most common in cats
-Melanoma
-Mast cell tumor
-Benign neoplasia
C/S
-Consistent with upper airway disease: noisy respiration, stridor, increased inspiratory efforts, change in voice
-Mass lesions can cause dysphagia, aspiration pneumonia, palpable mass
Dx
-Diagnostic imaging: rads, CT/MRI, laryngoscopy
-FNA and biopsy for histopath
-Staging disease once diagnosed with malignant neoplasia: local LNs evaluation, thoracic radiographs
Tx
-Depends on tumor type
-Surgical excision, laryngectomy with permanent tracheostomy
-Radiation therapy
-Chemotherapy: e.g., lymphoma
-NSAIDS: Cox-2 inhibition can slow progression
Lecture 5
Lower respiratory tract
Trachea
Bronchi
Bronchioles
Alveoli
Interstitium
Vasculature of lungs
Diagnostic approach
Initial evaluation
-PE: complete systemic physical. Thoracic evaluation
-Radiographs
-Blood work: CBC
Auscultation
-Bronchial: most prominent in central area of lungs; tubular sounds over large airways
-Vesicular: most prominent in peripheral lung fields; “breeze blowing through leaves”
Abnormal lung (breath) sounds
-Decreased lungs sounds (pleural effusion, pneumothorax, mass lesions)
-Increased or harsh lung sounds, crackles, wheezes
Radiographs
-Most helpful tool for intrathoracic disease Dx
-Right and left lateral increase sensitivity
-Minimum 2 views: RL and VD
-Dorsoventral views are taken to highlight dorsal pulmonary arteries, and to lessen stress in the dyspneic patient
-Horizontal views to evaluate pleural effusion or cavitary lesions
Peak Inspiration
-Short exposure time
-Cervical radiographs to evaluate trachea and upper airway structures, if clinical signs suggest
-Vascular pattern: characterized by an increased or decreased in size of the artery or vein
-Bronchial pattern: characterized by “donuts and tram lines”
-Alveolar pattern: characterized by air bronchograms and lobar signs
-Interstitial pattern: characterized Structured (nodular) unstructured (diffuse) or a combination in an increase in lung opacity
-Pleural effusion:
Other Findings
-Lung lobe consolidation - entire lobe is soft tissue opacity
-Atelectasis
-Cavitary lesions: abnormal air accumulation in the lung (e.g., bullae)
-Lung torsion
Specialized Diagnostics
-Angiography: used to confirm pulmonary thromboembolism
-Ultrasonography: used to evaluate pulmonary mass lesions and guide collection of FNA samples
-CT/MRI: masses, metastatic disease, PTE, pneumonias, etc
-Nuclear imaging: used to diagnosis ciliary dyskinesia, pulmonary perfusion and ventilation
-Parasitology: direct observation, Blood tests, Cytology analysis of fluid or respiratory samples, Fecal flotation.
-Serology: fungal pulmonary disease: histoplasmosis, blastomycoses, coccidioidomycosis. Toxoplamosis, cryptococcus, heart worm disease.
Tracheal wash
-Transtracheal wash technique, transoral (endotracheal) technique
Broncoalveolar lavage
-Bronchoscopic
-Nonbronchoscopic
Transthoracic lung aspiration
-Ultrasound guided FNA of pulmonary parenchyma
-Potential complications include pneumothorax, hemothorax, and pulmonary hemorrhage
-Can be utilized for masses near body wall and diffuse interstitial lung disease
Bronchoscopy
-Evaluation of major airways
-Bronchio-alveolar lavage (BAL) put sterile fluid in
-Technique of choice for always foreign body removal
What are the three signs of LRD?
- Cough
- Exercise intolerance
- Respiratory distress
Transtracheal wash
Transoral/endotracheal wash
Canine ITB/CIRDC “Kennel cough”
Pathophysiology
-Viruses, bacteria, and mycoplasma (any or all)
-Most commonly parainfluenza virus, adenovirus with Bordetella bronchiseptica
-Highly contagious from aerosol or direct contact (rarely fomites)
Signalment/history
-Young, unvaccinated dog
-Boarding, parks, etc, exposure
C/S
-Loud, goose-honk cough
-Cough often productive, foamy, clear liquid
-Post-tussive gagging is common
+/- Mucopurulent ocular and nasal discharge, sneezing
Physical examination
-Uncomplicated cases - tracheal sensitivity, normal lung sounds, generally self-limiting
-Complicated cases - fever, crackles or wheezes, anorexia, can progress to bronchopneumonia
-10-14 days resolution usually
Diagnosis
-Uncomplicated cases - empirical (experienced based)
-Complicated cases: CBC, chest radiographs (remember contagious), +/- tracheal wash with cytology and culture
-Highly contagious - coughing dogs should wait in the owner’s vehicle until the exam, avoid exposing other patients
Treatment
-Uncomplicated: typically self limiting, 10-14 days resolution
-Anti-tussives (butorphanol, hydrocodone, tramadol)
+/- anti-inflammatory doses of corticosteroids
+/- antibiotics - empiric choices (doxycycline, amoxicillin: clavulanic acid, trimethoprim sulfa, enrofloxacin)
-Mycoplasma and Bordetella - Doxycycline
-Complicated: antibiotics, culture of tracheal wash fluid is best
-Nebulization of antibiotics (GENTAMICIN) most effective
-Supportive care including maintaining hydration, corticosteroids, courage and nebulization
Prevention
-Vaccine not 100% effective
-Bordetella whiten 5 days
-intranasal Parainfluenza and Bordetella within 5 days
-CAV-2 and Bordetella Parenteral within 14 days
Collapsing Trachea
Pathophy
-Dorsoventral collapse of airway upon inhalation
-Intrathoracic, extra thoracic, and/or mainstream bronchi involvement
-Self-perpetuating
Signalment
-Middle aged to older toy and small breed dogs
C/S
-Dry, non-productive cough
-Worsens with excitement/exercise
-Occasionally associated with post-jussive gagging/retching
-Increased inspiratory effort with extra thoracic
-Increased expiratory effort with intrathoracic
-May present in dyspneic crisis
-Tracheal sensitivity common
Dx
-Radiographs
-Fluoroscopy
-Tracheobronchoscopy - best
-Tracheal wash may be help in ruling out other diseases
Tx
-Combination often needed
-Stable patient: bronchodilators (theophylline, terbutaline, albuterol), anti-inflammatories corticosteroids, antitussives (butorphanol, hydrocodone)
-Weight loss
-Avoid environmental triggers (fragrances)
Dyspneic collapsing trachea patient
-Oxygen
-Anxiolytics (acepromazine, butorphanol, diazepam)
-Nebulization
-Corticosteroids
-Surgical placement of stents
Lecture 7
Pulmonary parenchyma disease
Viral Pneumonia
Bacterial pneumonia
Aspiration pneumonia
Fungal pneumonia
Pulmonary parasites
Eosinophilic lung disease
Idiopathic interstitial pneumonia
Pulmonary neoplasia
Pulmonary hypertension
Pulmonary thromboembolism
Pulmonary edema
Bacterial Pneumonia
-Aspiration pneumonia
-Hematogenous route spread
-Immunocompromised animals
-Underlying respiratory disorder (ciliary dyskinesia, chronic bronchitis)
-Not contagious
Bordetella - Puppies
Adults - E. coli, Pasteurella, Bordetella, Streptococcus, Staphylococcus, Klebsiella, Enterococcus, and Pseudomonas
-Anaerobes present in mixed infections where lung lobe consolidation is present
C/S
-Lethargic, pyrexia, anorexia
-Tachypnea to dyspnea
-Increased respiratory phase/effort (inspiration most notable)
-Soft, productive cough
-Nasal discharge
-Crackles or increased bronchovesicular sounds
-Pale or cyanotic mucous membranes
Dx
-Radiographs
-Patchy interstitial and alveolar patterns most common
-Consolidation of lung lobe
-Pleural fissure lines, lobar signs
Cranioventral distribution common with aspiration pneumonia
-Caudal or diffuse distribution common with marked interstitial involvement hematogenous bacterial pneumonia
-CBC - inflammatory leukogram, with left shift
-Blood gas/pulse oximetry <90%
-BAL or TTW culture
-Misc: fecal flotation, serum chem, UA, HWT
Tx
-Oxygen - SpO2 <90% = cage or nasal canula
-Loosen secretions, vaporization, nebulization and or courage
-Antimicrobial therapy
-Antimicrobial: culture of septum, BAL, or TTW. Non-responsice to empirical treatment, chronicity, minimize costs
-Bronchodilators
-Physiotherapy: turn animal every 2 hrs if recumbent
-Mild exercise to promote coughing
Fungal Pneumonia
Canine
-Blastomycosis and coccidioidomycosis most common: skin lesions, draining
-Histoplasmosis possible
Feline
-Histoplasmosis and cryptococcosis most common: chronic nasal discharge
-Blastomycosis and coccidioidomycosis possible
C/S
-More chronic
-Weight loss
-Cyclic fever
-Lymphadenopathy
-Blastomycosis: skin lesions, bone, ocular
-Coccidioidomycosis: bone, joint, CNS
-Histoplasmosis: diarrhea in dogs
Dx
-Radiographs: similar to neoplasia pattern
-Diffuse military or nodular pattern
-May occasionally see pleural effusion (chronic) and “mass” lesions
Fungal Pneumonia
Dx
-Serology
-Urine antigen test 94% sensitivity
-CBC, Chem, UA - nonspecific findings: normochromic, normocytic anemia, leukopenia, leukocytosis, hyperglobulinemia, proteinuria
-Cytology: really important
-Skin lesions - Blasto; nasal cavity swabs
-FNA of lungs and/or LNs
-FNA or spleen, liver, affected organs
-TTW or BAL
Tx
-Systemic antifungals
Itraconazole
-Fluconazole
-Ketocanazole
-Prednisone - control inflammation
-Supportive
-60-90 days often 6 mts or longer
-Treat 2 months past resolution of signs
-High change of recurrence
Cases
Parasitic Pneumonia
Capillary aerophila
-Dogs and cats
-Small nematode beneath epithelial surfaces of airways
-Usually asymptomatic
-May show allergic bronchitis
Dx
-Radiographs signs of bronchial or bronchointerstitial pattern
Tx
-Fenbendazole
Pulmonary Neoplasia
-Primary pulmonary tumors: carcinoma. Malignant - begin as single mass lesion
-Surgical lobectomy beneficial if caught early
-Metastatic pulmonary tumors: extensive capillary network allows blood-borne neoplastic cells to deposit within lungs
-May present as multi-nodular, single nodule, or mass
Pulmonary Edema
-Mechanisms of edema include decreased plasma oncotic pressure, vascular overload, lymphatic obstruction, and increased vascular permeability
-Edema initially accumulates in the interstitium, moving rapidly to the alveoli
-Respiratory function is compromised by atelectasis, compression of alveoli and decreased surfactant concentration
Dx
-Rads: early changes = interstitial pattern
-Progress to alveolar pattern
Tx
-Activity restriction, minimize stress
-Hypoxemia treated with oxygen supplementation
-Bronchodilators (methylxanthine)
-Furosemide: not if hypovolemic
-Correct underlying cause
-Cardiogenic edema, over hydration, low oncotic pressure - colloids, plasma. Vascular permeability - difficult to treat, look for underlying cause
Lecture 8
Pleural and Mediastinal Disease
General considerations - Pleural abnormalities
-Accumulation of fluid (pleural effusion)
-Accumulation of air (pneumothorax and pneumomediastinum)
-Respiratory dysfunction is associated with interference with normal lung expansion
-Exercise intolerance - overt respiratory distress
-Abdominal effort may be increased
-Increased inspiratory effort
-Paradoxical movement of abdomen inwards during inspiration
-In cats with mediastinal masses, decreased compliance of chest wall in cranial thorax
Radiography
-Pleura is not normally visible on radiographs
-Individual lung lobes are not distinguished
-Abnormalities include pleural thickening, pleural effusion and pneumothorax
-Pleural thickening produces pleural fissure lines ~ 50-100 ml fluid
Pleural Fluid
- Transudates
<2.5-3.0 g/dl protein
<500-100/microL nucleated cells
-Primary macrophages, lymphocytes, mesothelial cells
-Increased hydrostatic pressure: Right CHF, pericardial disease
-Decreased plasma oncotic pressure: hypoalbuminemia <1g/dl
-Lymphatic obstruction: neoplasia, diaphragmatic hernias - Modified transudates
-3.5 g/dL protein content
5000/microL nucleated cell count
-Neutrophils and mononuclear cells
-Chronic diaphragmatic hernias - Exudates
-High protein > 3g/dl
->5000/microL nucleated cells
Nonseptic exudate: neutrophils (non degenerate), macrophages, eosinophils, lymphocytes, no organisms
-Ddx: FIP, neoplasia, chronic diaphragmatic hernia, lung lober torsion, resolving septic exudates
Septic
>50000-100000/microL nucleated cells
-Neutrophils (degenerate), organisms seen
-Ddx: pyothorax, spontaneous, penetrating wound, foreign bodies, extension of bacterial pneumonia.
- Chylous effusions
-Milky white and turbid due to Chylomicrons
-May be blood tinged
-Rarely: clear.colorless
>2.5 g/dl protein
400-10000/microL nucleated cells
-Lymphocytes
-Confirmation: triglycerides in fluid and serum higher than in pleural fluid
-Ddx: leaking from thoracic duct due to idiopathic, congenital, secondary, pericardial disease, lung lobe torsion, heartworm disease, or diaphragmatic hernia - Hemorrhagic effusions
-Grossly red
>3 mg/dl protein
>100/microL nucleated cells
-Erythrophagocytosis, inflammatory response, do not clot, and PCV lower than peripheral blood.
-Associated with trauma, coagulopathies, neoplasia (hemangiosarcoma), lung lobe torsion
-Activated clotting time and platelet count should be initially performed, followed by additional clotting tests as needed - Neoplastic effusion
-Can result in most effusion types
Lymphoma is the only neoplasia reliably identified in neoplastic effusion
-Difficult to establish diagnosis based on cytology
-Inflammation causes metaplastic changes in mesothelial cells, which are hard to distinguish from neoplastic cells
Pneumothorax
-Tension pneumothorax develops if air leaks through functional “one-way valve” lesion in the lungs
-Extrathoracic entry can occur after thoracic well trauma, iatrogenically through a chest tube, or during abdominal surgery if diaphragm is not intact
Of Pulmonary origin
-Blunt chest wall trauma
-Rupture of cavitary lung lesions (cysts, bullae, blebs, necrotic neoplastic tissue, abscesses, etc)
Mediastinal Masses
-Inspiratory distress due to displacement of lung tissue or secondary to pleural fluid accumulation
-Primary differential: Neoplasia (lymphoma common in cats)
-Thymoma, thyroid carcinoma, parathyroid carcinoma, and chemodectoma
-Non-neoplastic masses: abscesses, granulomas, hematomas, and cysts
CT
-More sensitive than rads for assessing the thorax
-Useful for evaluating extent of masses
-Increases likelihood of finding cavitary lesion in spontaneous pneumothorax
Thoracocentesis
-Indicated for collection of fluid or air from pleural space in the dog or cat
-Possible complications: lung laceration, hemothoraz, iatrogenic pyothorax
7th intercostal space, 2/3rd distance from constochondral junction to spine
-Aseptic technique
-Sternal or lateral recumbency
Chest Tube
-Indicated for tx of pyothorax and accumulating pneumothorax
-Burrowed SQ from 10th intercostal space to 7th intercostal space
Lec 9
Disorders of Pleural Cavity - Feline
Pyothorax
-Septic: most idiopathic origin in cats
-Can result from penetrating wounds, foreign bodies, migrating plant material, intrathoracic esophageal tears (usually foreign body)
C/S
-Tachypnea
-Decreased lung sounds
-Increased abdominal effort with inhalation
-Fever, lethargy
-Acute or chronic
-Asynchronous lung sounds
-Systemic inflammatory response syndrome, septic shock
Dx
-Thoracic rads
-Cytology of pleural fluid, aerobic and anaerobic cultures, Gram staining (filamentous gram +)
-Most bilateral in cats
-Possible mass lesions, pleural fibrosis, or lung lobe torsion
-Pre and post thoracocentesis rads
Tx
-Antibiotic
-Drainage of pleural space and supportive care
-Empirical choice of antibiotics initially
-Anaerobes and Pasteurella: amoxicillin/clavulonic acid PO, or ampicillin/sublactam IV
-Anaerobes: Clindamycin, metronidazole
-Add gram negative coverage: Fluoroquinolone or amino glycoside
-4-6 weeks antibiotics
Lavage pleural space
-Daily with 10ml/kg warm saline, slowly infuse, patient rolled on side to side gently
-Heparin to fluid can decrease fibrin formation
-Obtain thoracic radiographs every 24-48 hours
-Discontinue when volume decreases to <2ml/kg/day
-Cytology resolution of infection
Thoracotomy
-Indicated in animals not responding to medical therapy
-Suspected nidus of infection or foreign bodies
Pneumomediastinum secondary to a tracheal tear after rough intubation during a dental
Lung Lobe torsion
Chylothorax
-Congenital
-Traumatic (surgical or HBC)
-HF in cats, diaphragmatic hernia
-Non-traumatic - neoplasia, cardiomyopathy, pericardial disease, heartworm disease, lung lobe torsion, diaphragmatic hernia, systemic lymphagectasia
-Idiopathic
Originates from thoracic duct, gets dumped into jugular vein. Chyle contains triglycerides, lymphocytes, protein and fast-soluble vitamins
Breeds
-Afghan hounds, Shiba Inu, Siamese, Himalayan cats
C/S
-Lethargy
-Anorexia
-Weight loss
-Exercise intolerance
Dx
-Thoracic radiographs
-Evaluation of effusion (cells and triglycerides)
-Peripheral lymphopenia and panhypoproteinemia may be present
-Evaluate for underlying disease
Tx
-Resolve underlying disease
-Medical management: intermittent thoracocentesis (every 2 weeks)
-Low fat diet
-Administer RUTIN - Benzopyrone drug that decreases protein content of the effusion (promoting resorption of the fluid)
-Surgical ligation of the thoracic duct if not resolved within 3-4 months
-Peuroperitoneal or pleurovenous shunts may be utilized if all else fails
-50-80% response to surgical therapy
Spontaneous pneumothorax
GOLDEN RETRIEVER
-Rupture of cavitary lesions leads to spontaneous pneumothorax
-Occurs more often in dogs than cats
-Leads to rapid, profound respiratory distress following rupture if tension pneumothorax develops
Pulmonary Blebs < 1 cm
Pulmonary Bullae >1cm
Cavitary lesions
-Paragonimus infection
-Necrotic neoplasia
-PTE
-Abscesses and granulomas
-Congenital
-Idiopathic
-Traumatic
-Chronic always disease
-Bullae
Tx
-Thoracocentesis
-Medical treatment successful for Paragonimus (Fenbendazole)
-Most others surgical excision required
Tests to differentiate a chylous vs. purulent pleural effusion and Cervical mass
Compare triglyceride concentration
Evaluate cytology with Diff-Quick stain and a gram stain
Cervical mass
TFAST and check out chest tube and pericardial sites
Lecture 10
Emergency Management of Respiratory Distress and Oxygen Supplementation
Acid base status ROME
Respiratory Opposite
Metabolic Equal
Metabolic Acidosis
-pH: decreased
-PCO2: decreased
-HCO3: decreased
-Hyperventilation - compensatory
Metabolic Alkalosis
-pH: Increased
-PCO2: Increased
-HCO3: increased
-Hypoventilation - compensatory
Respiratory Acidosis
-pH: decreased
-PCO2: increased
-HCO3: increased
-Compensatory renal increased HCO3 resorption
Respiratory Alkalosis
-pH: Increased
-PCO2: Decreased
-HCO3: decreased
-Compensatory decreased renal HCO3 resorption
Acid-base status
Primary Hypoventilation
-Increased PCO2, respiratory acidosis
Primary hyperventilation
-Decreased PCO2, respiratory alkalosis
Metabolic acidosis
-Decreased HCO3, drives respiratory hyperventilation (secondary) and decreased PaCO2.
Metabolic alkalosis
-Increased HCO3, drives respiratory hypoventilation (secondary) and increases PCO2
Oxyhemoglobin Dissociation
PaO2: pressure of oxygen dissolved in arterial blood
SaO2: Oxygen saturation of hemoglobin is dependent on PaO2. Clinically measured by pulse oximetry
When PaO2 > 80 mmHg = SaO2 ~100%
Hypoxemia/Oxygen
-Hypoventilation
-V/Q (ventilation/perfusion) mismatch in the lung
-Diffusion abnormality
-Hypercapnia occurs with hypoxemia
-V and Q must be matched for blood to be fully oxygenated upon leaving the lung
-Poor ventilation occurs in most pulmonary diseases, ex edema, alveolar collapse, small airway obstruction (bronchitis)
-Poor ventilated lungs with normal blood flow have low V/Q
-A high V/Q ration is associated with pulmonary thromboembolism
