Lung Function And Respiratory Gases 3 Flashcards
What are the muscles of inspiration ?
Diahragm
External intercostal
Scalene
Sternoclediomastoid
Pectoralis muscles
Serratus anterior
Latissimus dorsi
What are the muscles of expiration?
Internal intercostal
Innermost intercostal
Rectus Abdominis
Transverse oblique
Internal oblique
What causes air movements?
Respiration has two phases- inspiration and expiration
What causes the movement of air during these phases?
Air moves because of pressure gradients
Boyles law
Charles law
What is boyles law?
The volume of a given mass of a fixed amount of gas is inversely proportional to its pressure provided the temp rapture remains constant
What is Charles law?
Gives the relationship between volume and temperature in an ideal gas where the pressure is constant
At constant pressure, volume (V) is directly proportional to the temperature (T).
V1/T1= V2/T2
At constant temperature, an increase in thoracic volume leads to decrease in pleural pressute
What’s the significance of muscles of respiration ?
Airtight chest wall allows for creation of pressure changes that facilitates the movement of air on inspiration and expiration
What is atmospheric pressure(PATM)?
- pressure exerted by the earth’s atmosphere
- 760 mmHg at sea level.
What is the alveolar pressure?
Pressure within the alveoli (PA)
Summarize the pressures and airflow gradients
Airflow because of pressure gradients
- Air flows into the lung when the alveolar pressure (PA) falls below atmospheric pressure (PATM)
- Air moves out of the lungs when PA becomes greater than PATM
- What influences the changes in PA?
Summarize the occurrences of respiration
During quiet respiration, inspiration 8s accomplished principally by contraction of the diaphragm and expiration is a passive process
The accessory muscles of respiration are utilized only with forced respiration
Air flows into and out of the respiratory tree because of the pressure gradient created by the changes in thoracic volume
