Volumes and Ventilation- Lecture 2

Question 1

Minute Ventilation

Answer 1

VE= VT * f

Question 2

P

B

Answer 2

Barometric pressure

Question 3

P

PL

Answer 3

Pleural pressure

Question 4

P

A

Answer 4

Alveolar pressure

Question 5

Collapsing forces of the lungs

Answer 5

Surface tension.

Lung elastic recoil.

Question 6

Compliance

Answer 6

= delta V (mL) / delta P (cmH2O)

Question 7

Breath

Answer 7

Defined as an inspiration and the subsequent expiration.

2 phase: inflation and deflation phase.

Question 8

Airflow is zero when…

Answer 8

At the beginning of a breath and when the inspiration is complete.

Question 9

Laplace law

Answer 9

P = 2τ/r
When radius decreases the increase required to keep bubble open particularly important with microscopic alveoli, need to reduce τ to minimize P and prevent alveolar collapse.

Question 10

Alveolar type II cells

Answer 10

Produce surfactant.

Surfactant reduces surface tension between the watery substance around it to prevent collapse

Question 11

Surfactant

Answer 11

(water/oil barrier) Reduces surface tension between the watery substance around the alveolar cell to prevent collapse and transudation. Lose of surfactant can lead to lung collapse and edema.