Lab 14 - Respiratory Physiology Flashcards
What is tidal volume (VT):
The volume breathed in each minute
- Normal breath
What is Expiratory Reserve Volume (ERV)
The maximal amount of air that can be exhaled from the lungs after a normal expiration.
- Amount of air that can be expired forcibly beyond the tidal volume
What is residual volume (RV)
The volume of gas left in the respiratory system after exhaling maximally.
- Air that cannot be expelled
What is Vital Capacity (VC):
Measure of the maximum volume of gas in the respiratory system that can be exchanged with each breath.
- Biggest possible breath
What is Total Lung Capacity ( TLC)
Measure of the volume of gas in the respiratory system at the end of a maximal inspiration.
What is major difference between volume and capacity in the respiratory system
A capacity is the sum of at least two volumes.
What is Forced Expired Volume ( FEV1)
Provides a measure of the resistance of the airways to flow.
What happens during normal resting respiration in the same breath
The volume of the exhaled gas exceeds that of the inhaled gas.
What is spirometry used for
Recording respiratory variables
Where does gas exchange between air and blood occur
In the alveolar air sacs
What is the efficiency of gas exchange dependent on
Ventilation; cyclical breathing movements alternately inflate and deflate the alveolar air sacs
What does inspiration do
Provides the alveoli with some fresh atmospheric ai
What does expiration do
Removes some of the stale air, which has reduced oxygen and increased carbon dioxide concentrations.
Why is spirometry becoming more important
- As respiratory dieseases are increasing world wide
- Spirometry is the method of choice for a fast and reliable screening of patients suspected of having Chronic Obstructive Pulmonary Disease (COPD).
What is COPD
- The 12th leading cause of death worldwide and the 5th leading cause in Western countries.
- Studies suggest COPD could climb to be the 3rd leading killer by 2020.
- Most COPD cases are completely avoidable; 85-90% of cases are caused by tobacco smoking.