Respiratory Revision

RESPIRATORY

REVISIONS

TRACHEAL COLLAPSE

Causes a reduced luminal diameter of the trachea

Predispositions – obesity, breed, hereditary, nutritional deficiencies (chondroitin
and/or glycoproteins) or chronic airway disease

Clinical signs - Dyspnoea, dry honking cough, retching, tachypnoea, exercise
intolerance. Worsened by excitement, heat, humidity, exercise or obesity

Diagnosis - History and clinical signs, Radioigraphy, Fluoroscopy , Tracheoscopy

Treatment:
• Surgical – stent

• Medical – oxygen therapy, weight loss, bronchodilators, use harness, manage

diet, bailey chair – NO steroids

LARYNGEAL PARALYSIS

Paralysis of the arytenoid cartilage – unilateral
or bilateral

Causes a restriction in the diameter of the airway

Treatment
• Medical
• Surgical – suturing the arytenoid cartilaginous folds

THE MUCOCILIARY ESCALATOR

Location – trachea, bronchi and bronchioles

Goblet cells + sol layer + gel layer =
mucociliary escalator

Function – trap, inhibit, destroy and remove
inhaled particles/pathogens

Goblet cells produce mucus. Function of mucus –
trap, humidify and hydrate

Excess mucus – increased viscosity, and narrowed
airways. However, does promote coughing, which
helps to clear

FELINE ASTHMA

Acute or chronic inflammation

No definitive diagnosis, process of elimination

Pathology –
• Exposed to allergen, and the body creates specific antibodies.
• Exposed to that antigen or allergen again, triggers the following events
• Inflammatory response/ mast cell rection - increases mucus, bronchoconstriction, inflammed airway
• Immunoglobulin E (IgE) --> histamine and leukotrienes result in increased vascular permeability and

smooth muscle contraction & eosinophils worsen the inflammation and tissue damage

All these processes cause an inflammation and limits the ability of air to move which
causes dyspnoea.

PNEUMONIA

Inflammation of the lungs

Lots of different types depending on
causative agents – e.g.,
• Bacteria – bordetella, pasterlla (cats),

streptococci

• Viruses – feline viral rhinotracheitis, canine

adenovirus 1+2, canine distemper virus

• Irritants
• Allergens
• FBs

ACIDOSIS VS ALKALOSIS

Acidosis

Respiratory acidosis

Retention of CO2

Hypoventilation

Cardiopulmonary arrest (not breathing)

Neurological hypoventilation

Opioids/GA

Alkalosis

Respiratory alkalosis

Excess ventilation – hyperventilation

Pain

Fever

Anxiety

Hypoxaemia

Secondary - Response to metabolic acidosis!

CASE EXAMPLE

A 1-year-old cat is admitted with severe respiratory distress. The cat had undergone
a routine ovariohysterectomy three days ago at your practice. Please discuss the
following:

1.

Initial stabilisation/emergency care

2.

Diagnostic tests + suspected diagnosis

3.

Treatment plan – clinical signs include dyspnoea, wheezing/crackles, cough,
orthopnoea, nasal discharge

Multiple Choice

A cat is showing signs of dyspnoea following a road traffic accident. Which position should they be placed in for a conscious thoracic radiograph?

• left lateral

• sternal

• dorsal

• right lateral

Open Ended

What is rhinitis?

Multiple Choice

Which of the following is an effective antitussive in dogs and cats?

• Medetomidine

• Prednisolone

• Codeine

• Bromhexine

Open Ended

State ONE common corticosteroid used in respiratory cases?

Open Ended

State ONE common bronchodilator used in respiratory cases?