Respiratory

Question 1

What pCO2 is incompatible with life?

Answer 1

80 mmHg (normal 35-45 mmHg)

Question 2

What is glycopyrrolate?

Answer 2

Antimuscarinic (bronchodilator)

Used for COPD

Question 3

What are the stages of pneumonia?

Answer 3

1. Congestion
2. Red hepatisation
3. Grey hepatisation
4. Resolution

Question 4

What are the 4 Ts of a mediastinal mass

Answer 4

Thymoma

Teratoma (and other germ cell tumors )

Thyroid neoplasm

Terrible lymphoma

Question 5

What causes an increased residual volume in COPD?

Answer 5

Reduced alveoli recoil

Question 6

How does hyperinflation help preserve maximal expiratory airflow in COPD?

Answer 6

Pressures generated by elastic recoil increase

Question 7

At which oxygen saturation do patients become centrally cyanosed?

Answer 7

≤85 percent

Question 8

Name a SAMA

Answer 8

Ipratropium

Question 9

Name a LAMA

Answer 9

Tiotropium

Question 10

What is theophylline?

Answer 10

A methylxanthine

Inhibits metabolism of cAMP by phosphodiesterases

cAMP stimulates B-adrenoceptors, causing bronchoconstriction

Question 11

What FEV1/FVC is diagnostic for COPD?

Answer 11

< 0.7

Question 12

How does CO diffusing capacity help differentiate emphysema and chronic bronchitis?

Answer 12

Decreased CO diffusing capacity suggests emphysema

Question 13

What is alpha-1-antitrypsin?

Answer 13

Inhibitor of the proteolytic enzyme elastase

ATT protects against the proteolytic degradation of elastin

Question 14

What is the most common cause of SVC syndrome?

Answer 14

Lung cancer

• Compression of the SVC reduces venous return to the right atrium*
• Feeling of fullness in the head, dyspnoea, oedema of the upper extremities and face*

Question 15

How is acute pulmonary oedema managed?

Answer 15

LMNOP

Loop diuretic/lasix

Morphine

Nitroglycerin

Oxygen

Position/prop up the patient

Question 16

What is the definition of pulmonary hypertension?

Answer 16

mPAP > 25 mmHg (normal 10-14 mmHg)

Question 17

What is the definition of cor pulmonale?

Answer 17

Altered structure (hypertrophy/dilation) or function of the right ventricle due to pulmonary hypertension from a primary disorder of the respiratory or pulmonary artery system

Question 18

How does COPD cause cor pulmonale?

Answer 18

Hypoxia → pulmonary vasoconstriction → increased pulmonary vascular resistance → cor pulmonale

(RV has to push against a higher resistance)

Question 19

What does bronchial breathing suggest?

Answer 19

Consolidation

Sounds from the bronchi are able to be transmitted to the lung fields

Question 20

What do bronchial breath sounds sound like?

Answer 20

Equal duration of inspiration and expiration (expiration usually 1/3 of the time)

Gap between the two phases

Tubular, hollow sound

Normally heard over the trachea

Question 21

What are the two types of respiratory failure?

Answer 21

1. Hypoxaemic (low PaO2)
   * V/Q mismatch, high altitude, hypoventilation, poor diffusion*
2. Hypercapnic (high PaCO2 and low PaO2)
   * Airway resistance, neuromuscular disorders, reduced respiratory effort*

Question 22

What does a monophonic wheeze suggest?

Answer 22

Obstruction of large airways e.g. tumour, foreign body

Question 23

What are the 5 mechanisms of hypoxaemia?

Answer 23

1. Hypoventilation
2. V/Q mismatch
3. Right to left shunt
4. Diffusion limiting
5. Reduced inspired oxygen tension

Question 24

What is V/Q mismatch?

Answer 24

An imbalance between blood flow and ventilation

Question 25

What happens if you over-oxygenate someone with COPD?

Answer 25

Excess O₂ inhibits peripheral chemoreceptors, decreasing their respiratory drive

Question 26

Which 4 drugs can be used for TB?

Answer 26

Rifampicin Isoniazid Pyrazinamide Ethambutol *RIPE*

Question 27

How do you differentiate a stridor from a wheeze?

Answer 27

Wheezes are musical

Question 28

Where is the obstruction in an inspiratory stridor?

Answer 28

Above the glottis ## Footnote * Negative pressure with inspiration further narrows the airway, causing stridor* * Expiratory = below the thoracic inlet*

Question 29

Where is the obstruction in an expiratory stridor?

Answer 29

Lower airways below the thoracic inlet ## Footnote *Inspiratory = above the glottis*

Question 30

Where is the obstruction in a biphasic stridor?

Answer 30

Subglottal/glottic down to the tracheal ring

Question 31

What does stony dullness on percussion of the lungs suggest?

Answer 31

Pleural effusion

Question 32

Where is the obstruction in an inspiratory stridor?

Answer 32

Laryngeal/supraglottic

Question 33

Where is the obstruction in an expiratory stridor?

Answer 33

Tracheobronchial - below the thoracic inlet

Question 34

Which lung volume equates the volume of air that can still be breathed in after normal inspiration?

Answer 34

Inspiratory reserve volume (IRV)

Question 35

Which lung volume equates the volume of air that moves into the lungs with each quiet inspiration?

Answer 35

Tidal volume (TV)

Question 36

Which lung volume equates to the volume of air that can still be breathed out after normal expiration?

Answer 36

Expiratory reserve volume (ERV)

Question 37

Which lung volume equates to the volume of air that remains in the lung after maximal expiration?

Answer 37

Residual volume (RV)

Question 38

Which lung volume cannot be measured on spirometry?

Answer 38

Residual volume

Question 39

What is functional vital capacity (FVC)?

Answer 39

The maximum volume of air that can be expired after a maximal inspiration

Question 40

What does the A-a gradient reflect?

Answer 40

The integrity of oxygen diffusion across the alveolar and pulmonary arterial membranes PAO2 - PaO2 Useful for determining the cause of hypoxemia. E.g. at high altitudes the A-a gradient will be normal because the alveolar oxygen concentration is low A = alveolar a = arterial

Question 41

What is the PERC criteria?

Answer 41

Pulmonary Embolism Rule Out Criteria

Question 42

What is this?

Answer 42

Westermark sign Peripheral lucency due to a hypoperfused area secondary to PE

Question 43

What is this?

Answer 43

Hampton hump Secondary to PE/pulmonary infarction

Question 44

What is the most specific sign of PE on ECG?

Answer 44

V1 + V3 T wave inversion

Question 45

What is a massive PE?

Answer 45

PE with haemodynamic instability

Question 46

What is a submassive PE?

Answer 46

Haemodynamically stable PE with right ventricular strain

Question 47

Which tools can be used to decide whether a patient with pneumonia should be admitted to hospital?

Answer 47

CRB-65 CURB-65

Question 48

Which tools can be used to identify patients with pneumonia who are at a higher risk of death or requiring intensive care support?

Answer 48

SMART-COP CORB

Question 49

How is a CURB-65 score calculated?

Answer 49

Question 50

How is a CORB score calculated?

Answer 50

Question 51

How is a SMART-COP score calculated?

Answer 51

Question 52

How is mild CAP empirically treated?

Answer 52

Oral amoxycillin OR doxycycline Outpatient

Question 53

How is moderate CAP empirically treated?

Answer 53

IV benzylpenicillin PLUS oral doxycycline Inpatient

Question 54

How is severe CAP empirically treated?

Answer 54

IV benzylpenicillin + IV gentamicin + IV azithromycin (HNE) OR IV ceftriaxone/cefotaxime + IV azithromycin (eTG)

Question 55

What is the difference between a transudative and an exudative pleural effusion?

Answer 55

**Transudative** Permeation of fluid through walls of intact pulmonary vessels Low protein **(\<50% of serum)** and cell count - Increased hydrostatic pressure **(CHF)** - Decreased oncotic pressure **Exudative** Exudation of fluid through lesions in blood and lymph Cloudy fluid with a high protein **(\> 50% of serum)** and cell count Pneumonia, tuberculosis Malignancy Pleural empyema Pulmonary embolism Vasculitis