Respiratory Physiology Lecture

Chapter 23

Respiratory Physiology 830-850

Pulmonary Ventilation

Mechanics of Breathing

Respiratory Rates and Volumes

Four Events of Respiration

Pulmonary Ventilation

External Respiration

Internal Respiration

Cellular Respiration

​Lung Cells

​External Respiration. Internal Respiration

Match

Match the following four Events of Respiration

• Pulmonary Ventilation

• External Respiration

• Internal Respiration

• Cellular Respiration

The movement of air into and out of the lungs

The movement of gases from the lungs into the blood stream

The movement of gases from the blood stream into the cells

The use of oxygen to produce energy for the cell

• The movement of air into and out of the lungs

• The movement of gases from the lungs into the blood stream

• The movement of gases from the blood stream into the cells

• The use of oxygen to produce energy for the cell

​Pressures and Membranes

Membranes

We first have to learn a little bit

about Pressures!!!

Drag and Drop

Robert Boyle observed the relationship between the pressure and volume for a gas sample. These two variables are ​​ ​

Placeholder

proportional.​ ​

Drag these tiles and drop them in the correct blank above

Inversely

directionally

equal in

3 Important Pressures

• Atmospheric

pressure

• Alveolar

pressure
(intrapulmonary
pressure)

• Intrapleural

pressure

Labelling

Label the lungs and their pressure.

Name the pressure in the red zone

Drag labels to their correct position on the image

Intrapulmonary

Intraplueral

Atmospheric

Labelling

Label the lungs and their pressure.

Name the pressure in the blue zone

Drag labels to their correct position on the image

Atmospheric

Intraplueral

Intrapulmonary

Labelling

Label the lungs and their pressure.

Name the pressure in the white zone

Drag labels to their correct position on the image

Atmospheric

Intrapulmonary

Intraplueral

3 Important Pressures

• Atmospheric

pressure

• Alveolar

pressure
(intrapulmonary
pressure)

• Intrapleural

pressure

Drag and Drop

If the atmospheric pressure is 760 mm Hg and the intrapulmonary pressure is 758 mm Hg air will flow ​

Placeholder

Drag these tiles and drop them in the correct blank above

Into the lungs

Out of the lungs

Air will not flow

Multiple Choice

Which of the following pressures must always be negative?

• atmospheric

• intraplueral

• intrapulmonary

• alveolar

Thoracic Volume and Inspiration

Reorder

Reorder the following Inspiratory events

• inspiratory muscles contract diaphragm descends, rib cage rises

• thoracic cavity volume increases

• lungs are stretched intrapulmonary volume increases

• intrapulmonary pressure drops

• air flows into lungs down pressure gradient until pulmonary pressure is equal to atmospheric

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

Thoracic Volume and Expiration

Reorder

Reorder the following Expiratory Events

• inspiratory muscles relax diaphragm rises, rib cage descends

• thoracic cavity volume decreases

• elastic lungs recoil, intrapulmonary volume decreases

• intrapulmonary pressure rises

• air flows out of lungs down pressure gradient until pulmonary pressure is equal to atmospheric

1

2

3

4

5

• 1
• 2
• 3
• 4
• 5

Changes in Thoracic Volumes

Pneumothorax and Atelectasis

Compliance

Compliance is an indication of lung

expandability, how easily the lungs expand and
contract.

–

Lower the compliance—harder to expand

- Greater the compliance- easier to fill

Factors that affect Compliance.

1. Loss of Supporting Tissue-

2. Surfactant production
3. Mobility of the Rib Cage

Surfactant

Pulmonary surfactant thus greatly reduces surface tension,
increasing compliance allowing the lung to inflate much more
easily, thereby reducing the work of breathing.

Multiple Choice

Premature babies....

• Have high amounts of surfactant therefore low compliance

• Have high amounts of surfactant therefore high compliance

• Low amounts of surfactant therefore high compliance

• Low amounts of surfactant therefore low compliance

Multiple Choice

Adding surfactant to the lung does what?

• Increases Compliance

• Decreases Compliance

• Increases Elasticity

• Decreases Elasticity

Elasticity

• Elasticity: tendency to return to

initial structure after being
distended

• What keeps the lungs from recoil?

Interpleural pressure

​Remember!

Physical Properties of the Lungs

• Compliance
• Elasticy

Multiple Choice

Compliance is ___________ proportional to lung recoil.

• Inversely

• Directly

Multiple Choice

Lung Compliance

• Ease which the lung expands or stretches

• The ease which the lungs recoil

Multiple Choice

As compliance increases

• harder for lung to expand & stretch

• easier the lung stretches & expands

Multiple Choice

In what instance would you find someone with lungs that have high compliance?

• someone with pulmonary fibrosis

• someone with emphysema.