Term
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Definition
– occurs in the lungs
– the exchange of O2 and CO2 between the air inhaled into the lungs and the blood flowing through pulmonary capillaries |
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Term
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Definition
– occurs all over the body
– the exchange of O2 and CO2 between the blood in the capillaries all over the body (the systemic capillaries) and all of the cells and tissues of the body |
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Term
| 1. List the functions of the respiratory system. |
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Definition
- exchanging oxygen for carbon dioxide
- voice production
- body temp regulation
- acid-base balance regulation
- sense of smell |
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Term
| 2. List the components of the Upper Respiratory system and the function of each component. |
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Definition
- nostrils
- nasal passages
- pharynx
- larynx
- trachea |
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Term
| 3. List the components of the Lower Respiratory system and the function of each component |
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Definition
- bronchi
- bronchioles
- alveolar ducts
- alveoli |
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Term
| 6. The pharynx is common to what 2 body systems? |
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Definition
| Common passageway for both the respiratory and digestive systems |
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Term
| 1. What are the anatomical divisions of the pharynx and describe each. |
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Definition
| - at its rostral end, the soft palate divides the pharynx into the dorsal nasopharynx (resp passageway) and the ventral oropharynx (digestive passageway) |
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Term
| 5. What is the bronchial tree and why is it named this? |
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Definition
- the air passageways that lead from the bronchi to the alveoli
- so named because they divide into smaller and smaller passageways much like the branching of a tree |
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Term
| Know the 3 different compartments, what they contain, and the defining clinical signs |
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Definition
Compartment I
– Nose, Nasal Cavity, and Paranasal Sinuses
– Sneezing and/or nasal Discharge
Compartment II
- Nasopharynx, Posterior nares (Choana), and Soft Palate
- Stertor and “Reverse Sneezing”
Compartment III
- Larynx
- Stridor |
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Term
| The 4 localizing clinical signs characteristically associated w/ upper resp are: |
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Definition
- sneezing and/or nasal d/c
- stertor
- stridor
- cough |
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Term
| 1. Why do you want to take radiographs prior to visual examination of the nasal cavity? |
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Definition
- Radiographs are always performed prior to visual examination of the nasal cavity. Manipulation of the tissue may result in intransal bleeding which will significantly complicate radiographic interpretation
- Radiographic interpretation of the nasal cavity and sinuses dictates that the clinician has a thorough understanding of the anatomy of the upper respiratory tract.
- Subsequently, with the patient still anesthetized, a visual examination of the nasal cavity should be attempted. |
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Term
| 1. About how much of the nasal cavity in dogs may be visualized using an otoscope speculum? |
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Definition
| - proximal 20 – 25% of the nasal cavity in most dogs |
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Term
| 1. What do you need to examine the caudal 75% of the nasal cavity? |
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Definition
| Visual exam of the caudal 75% can only be dine with a sm diameter endoscope. Computed tomography and MRI are important alternative dx tools but expense/availability are deterrents |
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Term
| 5. What are the 7 most common differential diagnoses for sneezing and / or nasal discharge? |
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Definition
- oronasal fistula
- nasal neoplasia
- Mycotic rhinitis
- Lymphoplasmacytic Rhinitis
- Foreign Body
- Infectious (bacterial, viral)
- Parasitic
- oronasal fistula - Especially common in middle-aged to older dogs, despite a history of recent dental prophylaxis. Empiric treatment with an orally administered antibiotic typically results in rapid and complete resolution of clinical signs, but only during the time the patient is receiving the antibiotic. Diagnosis is confirmed by probing the gingival sulcus of the upper canine teeth.
- nasal neoplasia - Most commonly reported in dogs between 8 and 10 years of age (Range: 1 to 15 years of age). No breed is predisposed, but is uncommon in brachycephalic breeds. Persistent nasal discharge, sneezing, and intermittent epistaxis are common presenting signs. Nasal radiographs may demonstrate lytic bone lesions' lysis of the vomer strongly supports neoplasia vs. mycotic rhinitis. Exposure to tobacco smoke has been associated with 2.5 time greater risk in long-nosed dogs. There is no or minimal response of the discharge to antibiotics. 80% of nasal tumors are malignant. Adenocarcinoma is most common, followed by squamous cell carcinoma. Sarcomas account for small number of nasal tumors.
- Mycotic rhinitis - Difficult to distinguish from neoplasia. Persistent and voluminous mucoid nasal discharge, with or without sneezing, and nasal pain are reported. Erosion of external nares is an important physical finding. Discharge is NOT responsive to antimicrobial treatment. Occlusal view radiographs of the nasal cavity may demonstrate evidence of turbinate destruction and/or increased fluid density on the affected side. 40% are 3 years or younger; 80% are 7 years and younger. The diagnosis is uncommon in brachycephalic breeds. Localized Aspergillus fumigatus is most commonly reported.
- Lymphoplasmacytic Rhinitis - Poorly described clinical syndrome associated with chronic sneezing and nasal discharge (bilateral or unilateral). Affected dogs are typically young to middle-aged, large breed dogs. Signs are NOT usually responsive to either antibiotics or steroids (topical or systemic). Diagnosis is based on ruling out other causes and nasal biopsy
- Foreign Body
- Infectious (bacterial, viral)
- Parasitic |
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Term
| 6. Does exposure to tobacco smoke increase the risk of development of neoplasia? |
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Definition
| Exposure to tobacco smoke has been associated with 2.5 time greater risk in long-nosed dogs |
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Term
| 1. What are the 2 most common causes of stertor? |
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Definition
- nasopharyngeal foreign bodies are by far the most common finding. Sticks, plant material (grass and juniper twigs), peas, cotton balls, and thread are examples.
- Neoplasia is the second most common finding
- In cats, lymphoma (FeLV-related) obstructing the choana is observed. In dogs, neoplasia is uncommon, but sarcomas in young dogs have been most often seen |
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Term
| 1. What is the most critical, and potentially life-threatening, upper respiratory sign? |
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Definition
- The least commonly encountered of the upper respiratory signs is stridor, or stridulous breathing.
- especially true when stridor is continuous. The patient that presents with continuous stridor deserves immediate attention. Every effort should be made to discern the cause once the clinical sign is characterized.
- In obtaining the history, owners generally describe 'wheezing' accurately; however, some patients may actually present for severe dyspnea or orthopnea.
- Careful questioning of the client is indicated to determine whether or not wheezing is associated with the additional effort to breath.
- The clinician should also make an effort to discern whether or not the owner has observed any change in the ability of the dog to vocalize or bark. |
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Term
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Definition
| Stridor is audible wheezing and is associated with restriction to airflow, usually at the level of the larynx |
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Term
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Definition
- Simply listening to the patient breath in a quiet room is the first step in assessing stridor. A stethoscope is not required to hear wheezing, but should always be used to examine the cervical trachea, the larynx, as well as the lungs. Any restriction to airflow in the larynx or cervical trachea can cause stridor. However, in the majority of cases, the stridor will be significantly louder at the level of the larynx, indicating a restrictive lesion at that level.
- If any indication of respiratory distress is reported or is manifest during the examination, the patient should be subjected to a visual examination under general anesthesia. Sedation is NOT sufficient to conduct the exam.
- Be Prepared! These patients are NOT routine. Emergency resuscitation may be required on induction of anesthesia, including the need to perform a tracheostomy.
- On induction...an endotracheal tube is carefully placed. If there are no complications associated with inserting the tube, once anesthesia is effectively induced and the patient is stable, a lateral and dorso-ventral radiographs of the larynx and cervical trachea are indicated. Metallic objects (e.g., fish hooks) can become buried in the mucosa and not observed during a visual exam.
- The endotracheal tube is removed in order to conduct a visual exam. A focal, hands-free light source directed into the oropharynx is strongly recommended. The epiglottis, arytenoid cartilages, glottis and vocal folds are carefully examined using a cotton-tipped applicator. Careful observation of the symmetry and function of the arytenoid cartilages is essential. The Left and Right cartilages normally respond to tactile stimuli when the patient is in a light plane of anesthesia; both sides should move to the medial plane rapidly and at the same time. They may not close, depending on the depth of anesthesia. It should be possible to visualize the cartilage on the inside of the tracheal rings while looking through the glottis. |
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Term
| 11. What are the differential diagnoses of stridor? |
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Definition
- In large breed, middle-aged and older dogs, laryngeal paralysis is the most common cause of stridor. Associated signs may include exercise intolerance and collapse during exertion
- Laryngeal paralysis and stridor may also be observed in young breeds as a congenital disorder (Dalmatian, Rottweiler, Bouvier des Flandres, Siberian husky, and bull terrier).
- Foreign body penetration of the laryngeal tissues can cause serious and life-threatening obstruction due to infection and swelling.
- Neoplasia may cause obstructive mass lesions involving larynx (esp squamous cell carcinoma/lymphoma
- Granulomatous laryngeal dz/funcal mycetoma
- Mass lesion, w/ no FB detected, need a bx. Must control post-bx bleeding – cotton-tipped applicator w/ 1:10,000 dilution epi held against site for 30 to 60 seconds |
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Term
| 12. Why is it important to know if a nasal discharge is unilateral or bilateral? |
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Definition
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Term
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Definition
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Term
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Definition
- Coughing is a reflex activity following stimulation of "cough receptors" which are located in the mucosa of the larynx, trachea, carina, and bronchi.
- The reflex is principally a defense mechanism that protects the lower respiratory tract and the alveoli. Inhaled irritants, mucus, and mechanical and positional changes in the lung stimulate the cough receptors.
- A single cough consists of a rapid, deep inspiration, followed by a forced expiration against a closed glottis, and then sudden opening of the glottis with continued expiratory effort to expel air and any possible substance stimulating the cough. This basic pattern can have many variants in both man and in animals. It may be repeated to produce a sudden outburst of coughing. Afferent nerves from the receptors pass via the vagus nerve to the medulla oblongata, from which efferents are distributed to the respiratory and laryngeal muscles. |
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Term
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Definition
| an accumulation of pus in the pleural cavity. |
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Term
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Definition
- Coughing is a reflex activity following stimulation of "cough receptors" which are located in the mucosa of the larynx, trachea, carina, and bronchi.
- The reflex is principally a defense mechanism that protects the lower respiratory tract and the alveoli. Inhaled irritants, mucus, and mechanical and positional changes in the lung stimulate the cough receptors.
- A single cough consists of a rapid, deep inspiration, followed by a forced expiration against a closed glottis, and then sudden opening of the glottis with continued expiratory effort to expel air and any possible substance stimulating the cough. This basic pattern can have many variants in both man and in animals. It may be repeated to produce a sudden outburst of coughing. Afferent nerves from the receptors pass via the vagus nerve to the medulla oblongata, from which efferents are distributed to the respiratory and laryngeal muscles. |
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Term
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Definition
| accumulation of blood in the pleural cavity (the space between the lungs and the walls of the chest |
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Term
| List some of the things which can cause coughing |
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Definition
- Acute or chronic laryngitis (most common cause of laryngitis in dogs is kennel cough, in cats herpesvirus and calicivirus
- Tracheitis – hard but nonproductive cough – dx hard, dry cough and sensitivity of trachea to palpation
- Infxn w/ filaroides osleri – dx by bronchoscopy
- Tracheal tumors – dx suggested by xrays and confirmed by bronchoscopy
- FB of plant origin in dogs/cats, marbles. Stones etc in dogs – dx by hx, rads (plant material not visible) and bronchoscopy
- Dorsoventral flattening of trachea in Yorkies and other toy/mini breeds, dx not always by rads, fluoroscopy better. Broncoscopy
- Hypoplasia of trachea – Eng Bulldog and some others – dyspnea most important clin sign, only in severe cases is cough the biggest sign
- Acute Bronchitis – usually infectious – kennel cough/feline influenza/k9 distemper (acute catarrhal bronchitis)
- Bronchopneumonia
- Chronic bronchitis – can be primary or develop secondary to an acute bronchitis
- Acute mucopurulent bronchitis
- Allergic/asthmatic bronchitis
- Tumors in bronchial tree or lung tissues – not always coughing but when coughing produces blood, tumor is likely
- Tumors in the trachea – predominantly dyspnea |
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Term
| 1. Are primary lung tumors common in the dog? Cat? |
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Definition
| Primary lung tumors are rare in dogs and cats; however, the reported incidence of lung carcinomas has increased at least 100% during the last 20 yr. This is attributed to an increased average life span, better detection and awareness, or, possibly, increasing exposure to environmental carcinogens |
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Term
| 1. What are “secondary” lung tumors? |
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Definition
| Secondary tumors occur through metastasis from a primary tumor |
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Term
| 1. Compare the radiographic appearance of primary lung tumors vs metastatic lung tumors. |
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Definition
Primary lung tumors
- in dogs may occur as single or multiple circumscribed mass lesions, as a diffuse lung pattern, or as a lobar consolidation.
- In cats, single circumscribed mass lesions are less common, whereas a diffuse lung pattern or lobar consolidation is more frequent.
- Pleural fluid accumulation is common in cats and less frequent in dogs. In either species, chest wall involvement and hilar lymphadenopathy may be seen.
Metastatic lung tumors
- Because of the limitations of routine radiography, small lesions (≤3 mm in diameter), which are present in ≥40% of cases with pulmonary metastasis, may not be seen |
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Term
| 5. About how large do the nodules need to be before you can see them well on radiographs? |
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Definition
| Greater than or equal to 3 mm in diameter |
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