Transcript Measuring Lung Capacity

Measuring Lung Capacity
Learning Intentions
• Explain the meaning of the terms tidal volume
and vital capacity.
• Describe how a spirometer can be used to
measure vital capacity, tidal volume, breathing
rate and oxygen uptake.
• Analyse and interpret data from a spirometer.
Vital Capacity Is
the maximum volume
of air that a person
can breathe in or
out in one breath.
Tidal volume is the
volume of air
breathed in or out
of the lungs in one
normal breath at
rest.
Spirometer
Is a high-tech
piece of
equipment
used to
measure vital
capacity, tidal
volume,
breathing rate
and oxygen
uptake.
•
Spirometer
• A spirometer consists of a chamber filled with
oxygen on a tank of water.
• A person breaths in the oxygen from the tank
causing the lid to sink. Breathing out causes
the lid to float up
• The movement of the chamber is recorded
using a data logger so that a spirometer trace
can be produced.
Spirometer Trace
Explanation of the trace
• Residual volume: is the volume of air that always
remains in the lungs even after the biggest exhalation
• Dead space: is the air in the bronchioles, bronchi and
trachea. There is no gas exchange between this air and
the blood.
• Inspiratory reserve volume: is how much more air can
be breathed in over and above the normal tidal
volume. You use this when exercising.
• Expiratory reserve volume: Is how much more air can
be breathed out over and above the normal tidal
volume.
Interpreting a spirometer trace
Measurement Male
Female
Tidal Volume
dm3
Vital Capacity
dm3
Breathing rate
breaths/min
Oxygen uptake
dm3/s
Answer the questions on the worksheet
Plenary