Respiratory Mechanics I

Question 1

Define Pnemothorax

Answer 1

Air enters the pleural space; Ppl rise (the - pressure holding pleua weakens); breaks connection between P & V pleura; P

Question 2

PA, P-pl, V-alv; EXPLAIN
During Inspiration & Expiration

What muscles initiate inspiration?

Answer 2

I: P-pl & PA (down), V-alv (UP)
E: P-pl & PA (UP), V-alv (Down)

External Intercostals & Diaphram

Question 3

FRC

Answer 3

Functional Residual Capacity: Start of a new breath: Elastic forces of chest and lung are equal and opposite

Question 4

Explain Atelectasis

Answer 4

Collapse alveoli due to surface tension. Difficult to restore.

Question 5

Name two functions of TII cells

Answer 5

1) secrete DPPC - surfactant

2) Differentiate into type I - repair alveoli

Question 6

Pressure caused by ST equation

Answer 6

2(tension constant)/Radius

• As radius increases ST pressure deceases - think Atelectasis