Anatomy

Question 1

What is ventilation?

Answer 1

Pressure gradient change in the thoracic cavity
-the diaphragm and the external intercostal muscles contract, which increases the size of the thorax and decreases the intra-thoracic pressure

Question 2

What 2 concepts affect ventilation?

Answer 2

1. Compliance

2. Resistance

Question 3

What is compliance?

Answer 3

It is a measure of the ease of the chest wall and lung expansion with increased lung volume and the collapse away from the chest wall with decreased lung volume

Question 4

What factors influence lung compliance?

Answer 4

• Alveolar surface tension
• Surfactant
• Elastic recoil of the lung

Question 5

What respiratory muscle fibres are fatigue resistant?

Answer 5

Type 1, 20% are found in the neonatal lung

Question 6

What percentage of alveoli are present at birth?

Answer 6

Approximately 15%

Question 7

At how many weeks is pulmonary surfactant considered sufficient to support the life of a premature baby?

Answer 7

At 28 weeks

Question 8

True or false?

The number of conducting airways is complete in early life?

Answer 8

True

Question 9

What is surfactant?

Answer 9

Secreted by Type 2 alveolar cells lining the inner surface of the alveolus
FUNCTION: Is to facilitate expansion of the alveoli during inspiration by increasing pulmonary compliance and decreasing surface tension

Question 10

What is pulmonary resistance?

Answer 10

It is directly related to airway size. The decreased airway diameter of a child, increases their risk of respiratory compromise

Question 11

What 4 factors influence resistance?

Answer 11

1. Diameter
2. Length
3. Gas viscosity
4. Flow rate viscosity