Help my dog can't breath

Question 1

In normal patients, the thorax and abdomen move?

Answer 1

Together and in the same direction, that is, both the rib cage and the abdomen will expand outwards on inspiration. This is called a synchronous pattern. Normal cats and dogs have a respiratory rate of 15 to 25 breaths per minute with only a small amount of thoracic and even less abdominal movement.

Question 2

As respiratory effort increases, thoracic and abdominal wall movement become more?

Answer 2

Obvious

Question 3

With severe inspiratory effort of any cause, a paradoxical or asynchronous pattern may develop where the abdomen?

Answer 3

moves in while the thoracic wall moves outwards.

Question 4

Why does an asynchronous pattern occur?

Answer 4

This occurs when the intercostal muscle contractions moving the ribs up and out on inspiration are powerful enough to pull the diaphragm forwards and hence the abdomen in.

Question 5

Common causes of asynchronous breathing include?

Answer 5

Upper airway obstruction, non-compliant (‘stiff’) lungs with a variety of parenchymal diseases, severe chronic pleural effusion and diaphragmatic rupture/paralysis.

Question 6

Physical examination of the dyspnoeic patient focuses on two things?

Answer 6

Sound and movement

Question 7

Look carefully at the expansion of the rib cage and whether there is any abdominal movement. Then, even before auscultation, listen for?

Answer 7

audible noises while doing a visual assessment of the patient’s respiratory effort. Decide whether any noises heard coincide with inspiration or expiration.

Question 8

There are characteristic noises associated with an abnormality of each major anatomical region; these regions are the upper airway, lower airway, parenchyma or pleural space.

Most upper airway obstructions – nares, pharynx, larynx, trachea – are characterised by?

Answer 8

Inspiratory stridor (a high-pitched, whistling musical sound) or stertor (a low-pitched snoring sound), and an open mouth on inspiration.

The exception to this rule is a complete obstruction of the larynx or trachea, such as that caused by a ball – these patients are literally gasping for breath, but make no noise. Urgent intervention is required for these patients.

Question 9

Careful and patient auscultation is the next step in localising airway lesions and should be used to discriminate between lower airway, parenchymal and pleural space disease.

Lower airway problems, typified by feline asthma, result in a?

Answer 9

high-pitched expiratory wheeze.

Question 10

Parenchymal problems, such as pneumonia or pulmonary oedema, will create?

Answer 10

harsh breath sounds and possibly crackles.

Question 11

Pleural space lesions will result in reduced lung sounds for the amount of breathing effort and decreased variation between inspiratory and expiratory breath sounds. If pleural space disease is present, auscultation can also help the clinician to decide whether it is an accumulation of fluid, air or soft tissue. If the pleural space is filled with air, then lung sounds will tend?

Answer 11

To be dull or absent dorsally.

Question 12

With pleural fluid, sounds will be?

Answer 12

Duller or absent ventrally and sounds may be harsher dorsally, resulting in a reversal of the normal distribution of lung sounds.

Question 13

With soft tissue, sounds will be?

Answer 13

dull in specific areas reflecting the distribution of the soft tissue. Percussion may also be useful, with pneumothorax being associated with hyper-resonance.

Question 14

Parenchymal disease (disease of the alveoli and/or pulmonary interstitium) is characterised by an?

Answer 14

inspiratory or mixed breathing pattern. On auscultation, pulmonary noises are generally louder than expected for the degree of breathing effort. Crackles may be heard and are more common as the disease worsens.

Question 15

There are a large number of differential diagnoses for the patient with parenchymal disease; some of the common ones seen in emergency patients are?

Answer 15

Pulmonary oedema

Pulmonary contusions

Pneumonia

Question 16

Discuss how you would proceed with investigating pulmonary oedema?

Answer 16

Radiographs are helpful in characterising its distribution. Pulmonary oedema secondary to cardiac disease has a characteristic perihilar distribution in dogs. Cardiac ultrasound can be used even in an emergency setting to assess the left ventricular wall thickness, contractility and the left atrial:aortic root ratio

Question 17

Initial medical management of pulmonary oedema secondary to congestive heart failure consists of?

Answer 17

principally of diuretics, such as furosemide 2 to 4 mg/kg intravenously every two to four hours. Severely affected cases may benefit from other drug therapies especially positive inotropes, such as pimobendan or dobutamine.

Question 18

Non-cardiogenic causes of pulmonary oedema in emergency patients include?

Answer 18

seizures, head trauma, electrocution and secondary to upper airway obstruction. Typically, non-cardiogenic pulmonary oedema and dyspnoea will develop in the hour following the inciting cause, although a delay of up to 12 hours is possible

Question 19

Pulmonary oedema radiographs often show?

Answer 19

Radiographs can show either an alveolar or interstitial pattern, with the dorsocaudal lung fields usually being the first and worst affected.

Question 20

Regardless of the aetiology of pulmonary oedema what should be done?

Answer 20

Oxygen supplementation is used to support the patient while medical management takes effect. Some patients require positive pressure ventilation due to the severity of the oedema.

Question 21

What are pulmonary contusions?

Answer 21

Pulmonary contusions are a common problem in trauma patients and occur when blood accumulates in the alveoli following blunt chest trauma.

Question 22

What needs to be conservative in patients with pulmonary contusions?

Answer 22

Intravenous fluid therapy in patients with pulmonary contusions needs to be conservative, with the aim of restoring perfusion while minimising the risk of increased pulmonary hydrostatic pressure with consequent worsening of contusions.

Question 23

How should pulmonary contusions be managed?

Answer 23

Nasal oxygen supplementation is often useful in mild-to-moderate cases. Prognosis in these cases is good although they may require oxygen support for two to three days.

Question 24

Viral, bacterial, parasitic and even fungal pneumonia may all be causes of?

Answer 24

parenchymal disease in patients presenting with dyspnoea

Question 25

Aspiration of gastric contents is a common causes of bacterial pneumonia, especially in dogs, and should be considered in any dog that becomes dyspnoeic following?

Answer 25

vomiting or dysphagia.

Question 26

With regards to pneumonia what will radiographs show?

Answer 26

Radiographs show that the changes are variable, with the right middle lung lobe being most commonly effected.

Question 27

What is ideally is done before therapy starts with pneumonia?

Answer 27

Ideally, samples for cytology and culture are obtained from the lungs before starting therapy. A transtracheal wash is an effective way of obtaining these samples in conscious or sedated emergency patients. Successful treatment relies on diagnosis of the underlying infectious agent.

Question 28

In the emergency situation how should pneumonia be appraoched?

Answer 28

oxygen supplementation should be used to alleviate the signs of dyspnoea. Fluid therapy should be used cautiously to avoid sudden increases in pulmonary hydrostatic pressure that may worsen pulmonary fluid extravasation. Empirical treatment for likely infectious agents should be started pending results of diagnostic tests.

Question 29

What parasite can cause pulmonary oedema?

Answer 29

Parasitic pneumonia (most commonly angiostrongylosis in UK) may be diagnosed by faecal smear or a Baermann’s test.

Question 30

What is the issue here?

Answer 30

Alveolar pattern? With interstitial?

Can see air bronchograms

There is some border obliteration around the apex of the heart.

Question 31

What is seen here?