Respiration lecture 6 Flashcards
What does the chest wall include?
the rib cage, diaphragm and abdominal wall
Explain how information travels from the brain to allow breathing
The brain sends a signal to the respiratory muscles, the muscles move the rib cage. The rib cage pulls the parietal pleura, which pulls the visceral pleura. Finally, the visceral pleura pulls on the lungs to make them expand.
Are the lungs directly attached to the chest wall?
No
How are the visceral and parietal pleura coupled together?
It’s a continuous membrane attached to the chest wall and the lungs to move together. In between, there is a small amount of liquid in the intrapleural space
What is the function of the liquid inside the intrapleural space?
it allows the lungs to slide against the internal wall of the chest during breathing and to follow the change in thoracic configuration
What is pleural pressure?
the pressure that can be measured in the liquid-filled space between lung and chest
What happens if a hole is punctured through the chest wall?
Air is going to enter the pleural space. The ribs are going to expand to their resting volume and the lungs will collapse to their resting volume
What do we measure to evaluate the elastic properties of the respiratory system?
changes in the recoil pressure of each separate structure for a given change in lung volume
(pressure put in vs volume attained for that pressure)
How are pressures measured for the respiratory system?
manometers or pressure transducers
How are volumes measured for the respiratory system?
Spinometry
What does “negative pressure” indicate?
pressure below the atmospheric pressure
What does “positive pressure” indicate?
Pressure above the atmospheric pressure
What is the recoil pressure defined as?
the pressure difference between the inside and outside of the structure
What is the trans-chest-wall pressure?
the difference between the pleural pressure and the pressure at the body surface
How can we measure pleural pressure?
using a flexible balloon introduced into the esophagus
Why does esophageal pressure provide a close approximation of pleural pressure?
because the esophagus is located between the two pleural spaces
What is the formula for trans-chest-wall pressure?
Pw = pleural pressure - body surface