Chapter 1 Distribution Flashcards
(47 cards)
What is the pons function in the respiratory system?
Assist in making a smooth transition between expiratory and inspiratory.
Chemoreceptors monitor?
Oxygen, carbon dioxide and blood ph levels. They have fibers that extend to the medulla.
Peripheral chemoreceptors are located? And respond to?
The are located in the aortic arch and common carotid arteries. They respond to hypoxemia, hypercapnia, and ph changes.
Central chemoreceptors location?
Located in brainstem. Respond to arterial carbon dioxide levels and blood ph.
Inspiration requires what type of pressure? What muscles are recruited?
Negative pressure. External intercostal muscles. Diaphragm.
Under increased ventilation demand Sternocleidomastoid and pectoralis major are recruited.
Expiration requires what type of pressure? What muscles are recruited?
Positive pressure ventilation. Abdominal muscles are recruited and intercostal muscles. Recoil from lungs.
Thin layers of surrounding tissue of lungs?
Visceral pleura, parietal pleura, and pleural space.
Generation of airways?
Trachea, main stem bronchi, lobar bronchi, segmental bronchi, terminal bronchi
What cells are found in the bronchi?
Cartilage, submucosal,glands, ciliates epithelial cells, goblet cells.
What are goblet cells? Function
Produce mucus. Foreign bacteria gets trapped in mucus, then cilia moves it upwards towards the pharynx.
What is lung compliance?
Measure of the stiffness of an object and is equal to the change in volume that occurs in the object.
Surfactants role in the lining of the alveoli?
Surfactant is the stability control, reduce surface forces.
What process does emphysema cause in the lungs?
Destroys lung tissue and reduces elastic recoil of the lung leading to a increase compliance.
Process that fibrosis causes in the lungs?
Fibrosis cause stiffening of the connective tissue in the lung and compliance.
Primary source of autonomic respiratory rhythm appears to reside in what region of the brainstem?
Medulla
Effects of surfactant in the lungs?
- increases pulmonary compliance
- reduces surface tension helps prevent alveolar collapse
- minimize transudation of fluid from the pulmonary capillaries.
Law of Laplace
where P as the pressure inside the sphere, T is the tension in the wall of the sphere, and r is the radius of the sphere.
What produce surfactant?
Type 2 pneumocytes
Cardiac arrest why do we not hyperventilate the pt to remove co2 and correct Acidosis?
The initial problem would be respiratory acidosis however the underlining problem is metabolic acidosis. The renal system has been impaired due to lack of perfusion. Thus enabling it to produce bicarb. It uses up all the bicarb in trying to neutralize the ph. Low bicarb levels then are present. We must increase perfusion so kidneys can produce more bicarb. The body will go into an anaerobic state due to the lack of oxygen and perform glycolysis which in turn will turn co2 into carbonic acid
Conditions that cause surfactant malfunction?
ARDS (pneumonia, sepsis, smoke inhalation) cause damage to the alveolar capillary.
Positive End Expiratory Pressure related to Law of LaPlace?
- The greater the radius of the alveolus, the lower the pressure in the alveolus.
- results in in a greater end exhalation.
- higher end expiratory pressure and volume, alveolar collapse is minimized.
Bernoullis principle? explain how a plane fly’s?
As the plane is propelled forward. The airplane is shaped so that the distance from front to back is greater on the top of the wing than on the bottom. So the flow is constant however the velocity is greater above the wing resulting in less pressure being exerted above the wing. Velocity is less on the bottom of the wing creating more pressure thus lifting the plane off the runway.
If the pulmonary alveolar pressure exceeds the pulmonary capillary pressure, what happens to the pulmonary capillary?
Since the alveolar pressure is greater , the capillary will be squeezed and blood flow will diminish or cease to the alveolus.
How many zones in the lung?
Which zone receives the most perfusion over ventilation ratio?
Pa>Pv>Palv
Zone 1, zone 2 and zone 3
Zone 1 has the least perfusion, no gas exchange in this area. Under upright position with normal cardiac output
Zone 2 some perfusion alveolar pressure is less and pulmonary artery pressure is greater. Some gas exchange
Zone 3 gas exchange occurs alveolar pressure allows for there to be good pulmonary artery pressure allowing for good perfusion to the alveolus.
