ANSWERS

1. Define the following terms: dyspnoea, tachypnoea, bradypnoea, hyperpnoea and orthopnoea.
   
   • Dyspnoea - difficulty breathing.
   • Tachypnoea - higher than normal respiratory rate.
   • Bradypnoea - lower than normal respiratory rate.
   • Hyperpnoea - panting/gasping.
   • Orthopnoea - difficulty breathing whilst in recumbency.
2. State the normal respiratory rate ranges for cats and dogs.
   
   • Cats - 20-30 breaths per minute.
   • Dogs - 10-30 breaths per minute (small breeds have a faster respiratory rate than larger breeds).
3. Fluid in the alveolar spaces may result in dyspnoea. Can you list 4 conditions that could cause dyspnoea of this nature?
   
   • Congestive heart failure.
   • Drowning.
   • Haemorrhage into the lungs.
   • Inhalation of irritant fumes.
4. List 4 conditions that could result in the collapse of the lungs.
   
   • Diaphragmatic rupture.
   • Haemothorax (blood in the thoracic cavity Eg from injury to soft tissues as a result of a fracture of a rib).
   • Pneumothorax (accumulation of air or gas in the pleural cavity as a result of pulmonary disease or perforation of the chest wall).
   • Pyothorax (accumulation of pus in the pleural cavity; also known as empyena).
5. State 2 differences between an open and closed pneumothorax?
   Open pneumothorax is caused by a wound penetrating from the skin down to the pleural cavity, whilst closed pneumothorax is caused by internal penetration of the lung or by a crushing injury to the lung - there is no wound leading from the body surface to the pleural cavity.
   In open pneumothorax cases air is sucked into the pleural cavity with each inhalation which destroys the negative pressure and causes the lungs to collapse, whilst in closed pneumothorax air from the damaged lung tissue fills the pleural cavity.
6. Can you list 4 poisons that cause dyspnoea by decreasing the oxygenation of the blood?
   
   • Paraquat poisoning (which causes the alveolar wall to thicken).
   • Chlorate poisoning (prevents oxygen uptake by haemoglobin due to the formation of methahaemoglobin).
   • Paracetamol poisoning (as chlorate).
   • Carbon monoxide poisoning (prevents oxygen uptake by haemoglobin due to the formation of carboxyhaemoglobin).
7. What is meant by asphyxia?
   A deficiency of oxygen in the blood and an increase in carbon dioxide in the blood and tissues; starvation of oxygen due to a restriction of inspired air reaching the lungs.
8. What is meant by hypoxia?
   A diminished amount of oxygen in the tissues.
9. What is the term that describes the cessation of breathing?
   Apnoea.
10. What is the name of the procedure employed to remove smooth foreign bodies if the patient has asphyxiated and is unconscious?
    The Heimlich manoeuvre.
11. What is meant by cyanosis?
    A bluish appearance of the skin and mucous membranes caused by imperfect oxygenation of the blood. This indicates circulatory failure and may be seen in cases of respiratory disease.
12. A Bull terrier is brought to the surgery with a piece of wire embedded in his chest. He is ambulatory but has laboured breathing. List your first aid actions.
    
    • Ask a colleague to take a history and ensure that a consent form for treatment is signed.
    • Introduce yourself to the patient and reassure him by talking softly.
    • Move the dog with extreme caution to the prep room - if necessary ask the owner to accompany him since a struggle at this stage could cause fatal complications.
    • Ensure that the dog's collar is not too tight and thus causing further respiratory distress and check the airway.
    • Administer pure oxygen by mask, again taking care not to distress the patient.
    • Ask a colleague to gently restrain and reassure the dog whilst you carefully cut back the protruding wire - DO NOT REMOVE THE PENETRATING PART OF THE FOREIGN BODY - this may lead to sudden lung collapse and death.
    • Apply a ring-pad dressing to prevent the remaining portion of wire from being pushed deeper into the wound.
    • If air can be heard hissing from the wound, place cling film over the damaged tissues to create an airtight seal, otherwise use a moist gauze pad.
    • Apply a chest bandage.
    • Continue to administer oxygen if necessary and monitor the dog's vital signs vigilantly.
    • Place an intravenous catheter in case the patient suddenly deteriorates.
    • It is essential to keep the dog warm, calm and above all, still; he should be encouraged to rest in sternal recumbency until the veterinary surgeon arrives.
13. Why is it that the dog in Q12 should be encouraged to rest in sternal recumbency?
    If the lung is damaged and the dog lies in lateral recumbency, pooling of blood or air may decrease the viability of the dependent lung.
14. List 4 clinical signs of respiratory obstruction.
    
    • Excessive inspiratory effort.
    • No passage of air observed with stethoscope.
    • "Snoring" noises from the soft palate in cases of partial obstruction.
    • Cyanosis.
15. List in order the first aid treatment to be given in a case of respiratory obstruction.
    
    • Extend the patient's neck.
    • Remove any constrictive collars or dressings.
    • Examine the mouth and pharynx, looking for and removing the cause of the obstruction if evident.
    • Pull the tongue forward (assess the colour of the mucous membranes).
    • Remove any blood or mucus by swabbing or suction.
    • Intubate if still obstructed and check patency of endotracheal tube, give intermittent positive pressure ventilation (IPPV) until the veterinary surgeon arrives .
    • If an endotracheal tube cannot be passed in the event of an acute upper airway obstruction, then a tracheotomy should be performed.
16. What is the difference between a tracheotomy and a tracheostomy?
    A tracheotomy is the creation of a temporary opening into the trachea in order to maintain the airway in the event of acute upper airway obstruction or to facilitate surgery, whilst a tracheostomy is a permanent opening into the trachea that is rarely indicated in cats and dogs.