Respiratory Infection

Question 1

What effect will fibrosis from bronchiectasis, if it is unilateral on the left, have on the position of the trachea and lung expansion on the left and lung volume on the right?

Answer 1

The trachea will be displaced towards the affected left lung. Decreased volume and decreased expansion will
result.

Fibrosis pulls the trachea towards the side of the lesion which is left in this case and expansion on that side is reduced. Lung volume on the right should be unaffected as fibrosis is unilateral and bronchiectasis is an obstructive lung disease \ lung volume should be normal.

Question 2

Does lobar pneumonia cause tracheal deviation or reduce lung expansion?

Answer 2

Reduced lung expansion but no tracheal

deviation

Question 3

Vocal fremitus

Answer 3

Vocal fremitus is the vibration felt when placing the hands on the back of a patient and asking them to speak: “99”

Question 4

Causes of Increased Fremitus

Answer 4

Pneumonia
Atelectasis
Lung cancer

Question 5

Causes of Decreased Fremitus

Answer 5

Pneumothorax
Emphysema
Haemothorax
Pleural effusion
Obesity

Question 6

Vocal resonance

Answer 6

Vocal resonance is the character of the patients voice heard with the stethoscope on the back.

Normal lungs filter out low frequency sounds and transmit high frequency sounds. Human voices are low in frequency and thus are not transmitted.

Consolidated lungs transmit low and higher frequency well therefore a patient’s voice is heard more clearly and easily over consolidated area.

Question 7

Causes of Increased Resonance

Answer 7

Pneumonia
Atelectasis
Lung cancer

Question 8

Causes of Decreased Resonance

Answer 8

Pneumothorax
Emphysema
Haemothorax
Pleural effusion
Obesity

Question 9

Bronchial breathing

Answer 9

Normally bronchial sounds are not heard over the lung fields, as the chest wall attenuates higher frequencies. In the presence of consolidation, these higher frequencies are able to be audibly transmitted.

Question 10

Crepitations

Answer 10

Crepitations are caused by the “popping open” of small airways and alveoli collapsed by fluid, exudate, or lack of aeration during expiration.

All forms of crackles are due to an accumulation of secretions along with inflammation or oedema which causes
the airways to narrow, obstruct or collapse.

Question 11

Inspiratory Crackles

Answer 11

Inspiratory crackles occur when negative pressure of inspiration causes airways that were previously collapsed to ‘pop’ open. Once open, there is sudden equalisation of pressure on either side of the obstruction \ resulting in vibrations of airway wall.

Question 12

Expiratory Crackles

Answer 12

− Trapped gas hypothesis whereby there are areas of airway collapse and positive pressure of expiration forces
open airways \ causing crackles as airways are forced open.

− Sudden collapse or closure of areas on expiration as pressure needed to keep small airways open are not
maintained on breathing out \ they collapse.

Question 13

Bronchitis Causes

Answer 13

Most viruses cause acute bronchitis and include rhinovirus, adenovirus, influenza A and B, and Parainfluenza virus

Bacteria in immunocompromised or people with underlying health problems. Mycoplasma pneumonia (*),
Streptococcus pneumonia (+), Haemophilus influenza (-), Moraxella catarrhalis (-), and Bordetella pertussis ()

Question 14

CAP Causes

Answer 14

Strep pneumonia (+), Haemophillus influenza (-), Klebsiella (-), S. Aureus (+)

Question 15

Patients susceptible to gram-negative infections

Answer 15

Hospitalized patients

HIV infection, chronic kidney disease, malnutrition and recent viral respiratory infection

Cystic fibrosis, COPD, Bronchiectasis, obstructive lesion, cigarette smoking

Excess alcohol and iv drug usage

On Immune suppressant therapy: corticosteroids