SFP: intro to the respiratory system Flashcards
What are the major clinical problems with lung function?
Impaired gas exchange, increased work of breathing, and obstructive/restrictive disease
Differentiate external and internal respiration
External involves the exchange of gases between cells of an organism and its environment, while internal involves utilizing O2 in cellular metabolism
What is the main drive for breathing?
CO2; we want to get it out. We normally breathe to get CO2 out more than we do to get oxygen in
What is the regulation method of breathing?
It is under central control; it is not autonomic
Describe regulation of breathing mechanics
Things in the blood such as O2, CO2, and pH are sensed by chemoreceptors, which then send signals to the control centers in the medulla. The signal is then sent through the phrenic nerve to control breathing.
What is the major muscle of breathing?
The diaphragm
Where does air exchange occur?
In the alveoli via capillaries
Pulmonary circulation is determined by…
SV of the right ventricle
What is bronchial circulation?
Blood coming from systemic circulation
Differentiate between pulmonary and systemic circulation
They have opposite mechanisms; in hypoxic conditions, vessels in the systemic system will dilate. However, pulmonary vessels will vasoconstrict
What is a normal PaCO2?
40
What is tidal volume?
The amount of blood moving in and out of the system with every breath
What is total lung capacity?
The max amount of air we can hold in the lungs
What is vital capacity?
What is residual volume?
The volume of air remaining in the lung after forcefully releasing vital capacity; we can never take all the air out of the lung
What is the conducting zone?
A portion of upper respiratory passages that is responsible for the bulk of air movement. Pressure gradients are critical for the air flow
What is responsible for the cough reflex?
The larynx; it reflexively closes to prevent food entering the trachea
What is a thoracentesis?
Putting a needle between the visceral and parietal pleura to bring fluid out
What is the significance of fluid in the pleural cavity?
It provides necessary surface tension to allow the lungs to move with the chest wall and keep the lungs open during breathing. Without it, the lungs would collapse
What is the advantage of negative pressure breathing in terms of alveoli?
The alveoli expand uniformly
What happens to alveoli during positive pressure breathing?
The inside alveoli inflate more than the outside alveoli, causing the outside alveoli to compress against the chest wall. This happens with ventilation.
What is dead space in the respiratory system?
Portion that does not participate in gas exchange
What receptor predominates in the bronchioles?
B2 (dilation) and M3 (constriction)
What are type I and type II cells in the respiratory zone?
Epithelial cells; type I are where gas exchange happens and type II are stem cells and cells that make surfactant
What are the main components of lung surfactant?
Lipids and protein
What is a major lipid in lung surfactant?
DPPC
What are the types of albumin in lung surfactant?
SP-A, B, C, D
What do SP-A and SP-D do?
Facilitate phagocytosis
What do SP-B and SP-C do?
Spread surfactant of alveolar surface
