Approach to dyspnoeic patient

Question 1

Normal respiration

Answer 1

Chest excursions visible but minimal effort apparent

Abdominal muscles should not be engaged

Patient comfortable and relaxed

Question 2

Increased respiratory effort

Answer 2

Muscular movement of both chest wall and abdomen increase

May extend head and neck, abduct elbows and show reluctance to lie down

Nostril flaring and mouth breathing if severe (cats may just be stressed)

Question 3

Decreased respiratory effort

Answer 3

Rarely seen

C1-C5 spinal lesions involving phrenic nerve and paralysing diaphragm

Muscular movements decrease

Patients may be tetraplegic but often concious

Question 4

Upper airway localisation

Answer 4

Inspiratory effort
Dont need a stethoscope to hear

Bypass obstruction (sedate and intubate)

Question 5

Lower airway localisation

Answer 5

Expiratory effort
Wheezes

Use a bronchodilator

Question 6

Pulmonary localisation

Answer 6

Variable resp pattern
Harsh sounds or crackles

Give oxygen and treat underlying cause

Question 7

Pleural space localisation

Answer 7

Shallow breathing
Dull and distant heart and lung sounds

Empty pleural space (thoracocentesis)

Question 8

When should thoracic radiography be performed?

Answer 8

Once the patient is more stable - additional stress may tip them over the physiological knife edge

Question 9

Thoracic point of care ultraound (POCUS)

Answer 9

used to assess for the presence of air, fluid, or soft tissue in the pleural space

as well as the presence and location of pulmonary parenchymal disease (‘wet lungs’)

Finally, the left atrium diameter can be assessed and compared with that of the aorta (LA:Ao ratio) to determine whether congestive heart failure is a likely underlying cause

Question 10

What does a collapsed lung look like from apical window on US

Answer 10

Fox tail

Question 11

What does a atelectatic lung appear as on US

Answer 11

‘Scorpion sting’

Question 12

What do ‘B lines’ indicate on ultrasound

Answer 12

Fluid in alveolar interstitium
E.g. congestive heart failure

Question 13

Flow-by oxygen

Answer 13

Simple and quick

provided via an oxygen port and tubing or anaesthetic machine and circuit

flow rate of 2-5 L/min with tubing held around 2 cm from the patient’s nose gives an inspired fraction of oxygen (FiO2) of 30-50%

Change position if patient distressed

tight face mask provides FiO2 up to 70% but is stressful in conscious patients

Short nasal prongs designed for people can be used in dogs, 50-100 mL/kg/min provides FiO2 of around 40-50%

Nasal cannulae extend to medial canthus of the eye, sutured in place

Can make an oxygen hood with cling film over a Buster collar

Question 14

Stabilisation of upper airways

Answer 14

Sedate and bypass obstruction

Question 15

Stabilisation of lower airways

Answer 15

Bronchodilator

Question 16

Common causes of upper airway obstruction in dogs

Answer 16

BOAS
Laryngeal paralysis

Question 17

Sedation for upper airway obstruction

Answer 17

Butorphanol, acepromazine, or dexmedetomidine

Question 18

Most common lower airway crisis

Answer 18

Feline asthma

Oxygen supplementation, mild sedation, bronchodilator

Question 19

Common causes of pulmonary parenchymal disease

Answer 19

Aspiration pneumonia
Congestive heart failure
Pulmonary contusions

No quick fix

Question 20

What should you use for thoracocentesis?

Answer 20

Dog: IV catheter
Cat: butterfly needle

Question 21

Where in the chest do you do a thoracocentesis?

Answer 21

Mid chest (IC space 8ish)
Cranial to rib

Question 22

What to do is air or fluid re-accumulates quickly?

Answer 22

Thoracostomy tube placement may be required

Question 23

WHat to do if thoracocentesis is required more than three times and reasonable volumes of air or fluid are drained wach time

Answer 23

Thoracostomy tube

Question 24

Types of thoracostomy tube

Answer 24

Over the wire (Seldinger) - preferable in emergency setting
Trochar