Pulmonary Physiology I
the number one determinate of airflow
What is "radius"?
Ficks Law of Equation States that diffusion increases with
Increased surface area
Increased pressure gradient
Decreased Thickness of barrier
What happens to pressure, volume, and flow during
a. inspiration
b. expiration
a. pressure inside lungs drops, volume increases, flow negative (vaccuum)
b. pressure inside lungs increases, volume decreases, flow increases
What substance protects lungs against invaders (immune response)
Surfactant
What is the abdominal paradox?
During inspiration, the abdomen moves inward
During expiration, the abdomen moves outward
It is suppose to move outward during normal inspiration
The paradox may indicate diaphragmatic weakness or fatigue
the two quantities that make up minute ventilation, and the definition of minute ventilation
Tidal volume (x) respiratory rate
The total air moved per minute
High compliancy means
that the lungs are not very stiff, high ability to expand
Expiration is a _____ process, with the relaxation of these muscles releasing air
passive; diaphragm and external intercostals
(internal intercostals aid in forced expiration)
What cells produce surfactant? What happens to compliancy if they do not?
Type II pneumocyte, low compliance
What is the zone of opposition? What happens if lungs are hyper inflated?
Where the diaphragm attaches to lower ribs (should be acute angle)
Hyperinflation means larger black area on Xray and zone of opposition with have a more obtuse angle
please describe Q= (change in P)/R
The air flow through the lungs is equal to the change in pressure (of atmosphere vs alveolar) divided by the resistance (of airway)
Hypoventilation will lead to _____, but hyperventilation will lead to ______
respiratory acidosis, respiratory alkalosis
what are the 5 factors that can change chest wall compliance?
aging: decreased compliance
obesity: adipose causes decrease compliance
kyphosis: decreases compliance
neuromuscular weakness: decreased compliance
pain/guarding: decreased compliance
Which lobe of the lung has to work the hardest to achieve ventilation?
the top lobe of the lung receives the least ventilation because the bottom part is compressed. The bottom will have the highest flow because air will want to stretch the area that has the path of least resistance.
Maximal Inspiratory Pressure measures
the lowest pressure developed during a forceful inspiration against an occluded airway
primarily measures inspiratory muscle length
recorded as a negative number
the two variables that describe tidal volume, and what the definition of tidal volume is
Dead space (air that does not participate in gas exchange) plus alveolar ventilation (what actually reaches alveoli) equals the amount of air moved in and out of the lung each breath
Sympathetic activation leads to ______ using this neurotransmitter.
Parasympathetic activation leads to ______ using this neurotransmitter.
(4 words for the answer)
bronchodilation, norepinephrine
bronchoconstriction, acetylcholine
three examples of pathologies that can decrease chest wall compliance
1. fusion of costovertebral joints
2. broken ribs
3. child born prematurely
Which way does the diaphragm move and is it inspiration or expiration in?
contraction:
relaxation:
descends inferiorly, inspiration
compresses superiorly, expiration
Maximal Expiratory Pressure Measures:
The highest pressure developed during a forceful exhalation against an occluded airway
measures expiratory muscle length
recorded as a positive number
Henderson-Hasselbach equation explained in regards to pH
pH is increases (alkalosis) with HCO3- (bicarbonate) because this bicarbonate buffer accepts H+ from PCO2
PH decreases (acidosis) when you have more PCO2 in blood (hypoventilation)
What are the three factors that can change lung compliance?
change in volume divided by change in pressure
inverse of elasticity (high compliance lungs will not want to recoil right after)
ability of tissue to expand
production of this decreases surface tension and allows easier inflation of lungs
surfactant
What is Boyle's Law in regards to normal movement of the anterior chest wall?
During inspiration, _____ goes up, but intrapulmonary _____ goes down.
and vise versa
Maximal Voluntary Ventilation is
the total volume of air exhaled during 12 second of rapid, deep breathing
primarily measures breathing reserve (Respiratory muscle endurance)
recorded as L/min