Physiology

Question 1

Level at which the esophagus, the vena cava, and the aorta enter the diaphragm

Answer 1

• Vena cava: T8
• Esophagus (and vagus nerve): T10
• Aorta (and thoracic duct and azygos vein): T12

Question 2

Parts of the respiratory tree that make up the conducting zone (anatomic dead space)

Answer 2

From nose to terminal bronchioles

Question 3

Parts of the respiratory tree that make up the respiratory zone

Answer 3

• Respiratory bronchioles
• Alveolar ducts
• Alveoli

Question 4

Part of the respiratory tree that contributes the most to airway resistance

Answer 4

Smooth muscles in the bronchi

Question 5

Aspiration of a foreign object in the upright position will go to which part of the respiratory tree

Answer 5

Posterior basal segment of the right lower lobe

Question 6

Aspiration of a foreign object in the supine position will go to which part of the respiratory tree

Answer 6

Superior segment of the right lower lobe

Question 7

Aspiration of a foreign object when lying on the right will go to which part of the respiratory tree

Answer 7

Right upper lobe

Question 8

Aspiration of a foreign object when lying on the left will go to which part of the respiratory tree

Answer 8

Lingula

Question 9

Part of the respiratory tree that has Goblet cells

Answer 9

Bronchi only

Question 10

Part of the respiratory tree that has Clara cells

Answer 10

Terminal bronchioles

Question 11

Cell type that serves as a stem cell for both ciliated cells and themselves

Answer 11

Clara cells

Question 12

Formula for pressure inside the alveolus

Answer 12

Pressure = 2 x surface tension / radius

Question 13

Lecithin:sphingomyelin ratio that indicates lung maturity

Answer 13

A ratio greater than 2

Question 14

Formula for inspiratory capacity

Answer 14

Inspiratory reserve volumen + tidal volume

Question 15

Formula for functional residual capacity

Answer 15

Expiratory reserve volumen + residual volume

Question 16

Formula for vital capacity

Answer 16

Inspiratory reserve volumen + tidal volumen + expiratory reserve volume

Question 17

Formula for physiologic dead space

Answer 17

VT x (PaCO2-PeCO2/PaCO2)

Question 18

Formula for alveolar ventilation

Answer 18

VA = (VT-VD) x RR

Question 19

Formula for minute ventilation

Answer 19

VE = VT x RR

Question 20

Formula for pulmonary vascular resistance

Answer 20

(Pressure in the pulmonary artery - Pressure in the left atrium) / CO

Question 21

Formula for oxygen content

Answer 21

(1.34 x Hb x saturation) + 0.003

Question 22

Formula for alveolar pressure of oxygen

Answer 22

PAO2 = PiO2 - (PaCO2/R)

*R: 0.08 (CO2 produces/O2 consumed)

Question 23

Lung capacity used as a marker for lung compliance

Answer 23

Functional residual capacity

Question 24

Errors in the development of the lung during which stage can lead to tracheoesophageal fistula

Answer 24

Embryonic (weeks 4 to 7)

Question 25

A fetus is capable of respiration at what developmental age

Answer 25

25 weeks

Question 26

Developmental age at which pneumocytes start to appear

Answer 26

26 weeks

Question 27

If therapeutic oxygen is given to a newborn with neonatal respiratory distress syndrome, what complications can occur

Answer 27

* Retinopathy of prematurity * Intraventricular hemorrhage * Bronchopulmonary displasia

Question 28

Part of the lung that is the largest contributor to alveolar dead space

Answer 28

Apex of healthy lung

Question 29

Deficiency of which enzyme leads to congenital methemoglobinemia

Answer 29

Deficiency of glutathione b5 reductase

Question 30

Formula for gas diffusion

Answer 30

Vgas = A x D x (P1-P2/T)

Question 31

Hypoxemia in a child with neonatal respiratory distress syndrome increases the risk to develop what two pathologies

Answer 31

* Patent ductus arteriosus (PDA) | * Necrotizing enterocolitis

Question 32

Point in pulmonary mechanics when resistance is the lowest

Answer 32

When functional residual capacity is reached (there is no active inspiration or expiration), because at this point the pressure in the airways is 0

Question 33

Renal response to high altitude

Answer 33

Increased excretion of bicarbonate to compensate for respiratory alkalosis

Question 34

Respiratory parameters that increase during exercise

Answer 34

* Ventilation (and therefore, the following) * Respiratory rate * Tidal volume

Question 35

Best way to increase alveolar ventilation

Answer 35

Increase tidal volume

Question 36

Why does PaO2 in the pulmonary veins and left heart decreases reaches a 100 mmHg, while in the alveolar capillaries the PaO2 reaches 104 mmHg

Answer 36

Because there is mixing of the alveolar capillary blood with deoxygenated blood from the bronchial veins *Thebesian veins also contribute to this normal shunting

Question 37

Blocking an airway would lead to the development of which zone below the level of occlusion

Answer 37

Zone 3

Question 38

Formula for pressure of inspired oxygen

Answer 38

PIO2 = (Patm - 47) x 0.21

Question 39

Part of the lung with the most compliant alveoli

Answer 39

The lung base