CVP exam 3 Flashcards
1
Q
Where are respiratory neurons located?
A
Brainstem
2
Q
What are the fcts. of those neurons?
A
Set basic drive of ventilation & activation of muscles of respiration
3
Q
What are the two respiratory centers?
A
Dorsal and ventral medullary group & pneumotaxic and apneustic centers
4
Q
The respiratory centers are influenced by? (3 things)
A
- higher brain centers 2. peripheral and central chemoreceptors 3. peripheral mechanoreceptors
5
Q
What are the major inspiratory muscles?
A
Diaphragm & external intercostals
6
Q
What are the major expiratory muscles?
A
Abdominals & internal intercostals
7
Q
Under resting conditions, expiration is passive and is associated with recoil of the lungs? (True/False)
A
True
8
Q
What is pleural P?
A
Negative P between parietal and visceral pleura that keeps lung inflated against chest wall
9
Q
Where does the alveolar P stands compared to the atmospheric P during inspiration?
A
Sub-atmospheric (Supra-atmospheric during expiration)
10
Q
Transpulmonary P peaks at the end of inspiration? (True/False)
A
True
11
Q
What 2 forces are opposed during inspiration?
A
Chest wall F v.s. lung recoil F
12
Q
É required for ventilation is 3.5% of tot. body É? (True/False)
A
True
13
Q
What is hyperventilation?
A
Pulmonary ventilation > metabolic demand
14
Q
What is hypoventilation?
A
Pulmonary ventilation
15
Q
What’s a pleural effusion?
A
Collection of large amount of free fluid in pleural space
16
Q
Surfactant reduces surface tension? (True/False)
A
True
17
Q
Only interdependence plays a role in stabilization of alveolar size? (True/False)
A
False, surfactant also plays a role
18
Q
What is tidal volume (TV)?
A
Amount of air moved in or out each breath
19
Q
What is inspiratory reserve volume (IRV)?
A
Max. vol. one can inspire above normal inspiration
20
Q
What is expiratory reserve volume (ERV)?
A
Max. vol. one can expire above normal expiration
21
Q
What is residual volume (RV)?
A
Vol. of air left in the lungs after max. expiratory effort
22
Q
What is functional residual capacity (FRC)?
A
Vol. of air left in the lungs after a normal expiration (RV + ERV)
23
Q
What is inspiratory capacity (IC)?
A
Max. vol. one can inspire during an inspiration effort (TV + IRV)
24
Q
What is vital capacity (VC)?
A
Max. vol. one can exchange in a respiratory cycle (IRV + TV + ERV)
25
What is total lung capacity (TLC)?
Air in the lungs at full inflation (IRV + TV + ERV + RV)
26
What diminishes with restrictive lung condition? (3 things)
VC, IRV & IC
27
There is around 300 million alveoli with a surface area of 150-200 square meter? (True/False)
False, 50-100 square meter
28
What is the anatomical dead space?
Airways (~150 ml)
29
What is the physiological dead space?
Anatomical + non functional alveoli
30
If the rib cage is immobile, how is inspiration possible?
By diaphragmatic breathing
31
What is transpulmonary pressure?
Measure of the recoil tendency of the lung
32
Which muscle of respiration is a stabilizer of the lumbar spine?
Transversus abdominis
33
If the visceral pleura erodes and allows a region of the alveolar space to communicate with the pleural space, what would happen to the functional residual capacity?
Decreased
34
What is hysterisis?
At the onset of inspiration, lung vol. changes at a slower rate then the pleural P changes
35
What act as a lubricant between pleura?
Pleural fluid
36
What effect will histamine binding to H1 receptors have on the airway smooth muscle
Constrict (H2 receptors = dilation)
37
Most of the recoil tendency of the lung is due to what?
Surface tension forces
38
What are the pathophysiologic consequences of hyperventilation?
SV & CO decreased; coronary blood flow decreased; repol. of heart impaired; oxyhemoglobin affinity increased; cerebral blood flow decreased; skeletal muscle spasm and tetany; serum potassium decreased
39
What is the major effect of sympathetic stimulation on airway smooth muscle?
Dilate, most of the effect is indirect via blood borne (circulating epinephrine)
40
Why is the left ventricular output slightly higher (1%) than the right ventricular output?
Some bronchial artery blood drains into the pulmonary veins
41
Which volumes or capacities cannot be determined with basic spirometry?
RV; FRC & TLC
42
What local effect will Prostaglandin E series have on airway smooth muscle?
Dilation (Prostagladin F series = constriction)
43
What has the greatest effect on constriction of the pre-capillary?
Low alveolar oxygen
44
Without surfactant, as alveolar radius increases, what happens to the collapse tendency of the lung?
Increase
45
During exercise in upright position, flow throughout the lung is equal? (True/False)
False
46
What condition can significantly increase total pulmonic blood volume?
Mitral valve stenosis
47
Compared to atmospheric air, alveolar air has a higher concentration of which gases?
CO2 and H2O
48
What effect does stimulation of the SNS have on sensitivity of peripheral chemoreceptors to hypoxia?
Increases
49
0.1% CO (P(CO) = 0.6 mmHg) can be lethal? (True/False)
True
50
What are the major fcts. of CO?
1. Signaling molecule in NS 2. Vasodilator
51
Not enough pulmonary blood flow (perfusion) for the amount of ventilation results in a decrease of physiologic dead space? (True/False)
False (Increase in physiologic dead space)
52
If the ventilation/perfusion ratio decreases below normal, what condition happen?
Increase in the amount of physiologic shunt blood
53
What happens to virtually all circulating prostaglandins in the blood as they pass through the pulmonary capillaries?
They are inactivated/cleared
54
What percentage of CO2 in the blood is carried in the form of the bicarbonate ion?
70%
55
Stimulation of stretch receptors in the lungs will have what effect on the dorsal respiratory group?
Inhibit
56
What would cause more oxygen to be released from hemoglobin? (shift to the right)
Decrease P(O2); increase P(CO2); decrease pH; increase in 2,3 diphosphoglycerate
57
Most of the ventilatory response to a slight increase in CO2 levels is mediated by?
Central chemoreceptors in the brain stem
58
The basic ventilatory drive is set by neurons in which area of the NS?
Dorsal respiratory group
59
Normal inspiration is usually terminated by which area of the NS?
Pneumotaxic center
60
What is the most prevalent cause of respiratory depression?
Narcotics
61
What are the complications associated with chronic mountain sickness?
Increase hematocrit; increase pulmonary arterial BP; enlarged right ventricle; decrease total peripheral resistance
62
Stimulation of what receptors, would create a feeling of dyspnea?
J receptors in the parenchyma
63
In acute mountain sickness, the subject suffers deterioration of nervous system function primarily due to what?
Hypoxia
64
What is the negative pleural pressure generated to expand the lung and open the alveoli during the first breath?
-40 to -60 cm H2O
65
Parasympathetic-muscarenic receptors cause bronchodilation? (True/False)
False (bronchoconstriction)
66
NANC nerves can either bronchodilate or bronchocontrict? (True/False)
True
67
How does environmental pollution affect the control of airway smooth muscle?
Elicit constriction of airways with parasympathetic reflex or local constrictor responses
68
How does the body react to respiratory acidosis?
Increase ventilation
69
How does the body react to respiratory alkalosis?
Decrease ventilation
70
What regulates CO2 P?
Lungs
71
What regulates HCO3 P?
Kidneys
72
The lungs are the only organ that receive blood flow in excess of the cardiac output? (True/False)
True
73
Under resting conditions, when is blood fully oxygenated?
By the time it has passed the 1st 1/3 of pulmonary capillaries
74
What is the oxygenation limiting factor in exercise?
Stroke Volume (SV)
75
During exercise, the entire lung is like a zone 1, which means that capillary P > alveolar P (blood flow from the capillaries to the alveoli)? (True/False)
False (entire lung is like a zone 3)
76
How is the excess fluid removed from the pulmonary capillaries?
Lymphatics
77
What is the solubility order of the pulmonary gases?
CO2 > O2 > He > CO > N2
78
Why is the alveolar air turnover slow?
Because it prevents a large changes in gas [C] in alveoli
79
What limits VO2 max?
Cardiac Output, not ventilation
80
What percentage of O2 is transported in a dissolved form?
3%
81
What percentage of O2 is transported bound to hemoglobin?
97%
82
What percentage of CO2 is transported in a dissolved form?
7%
83
What percentage of O2 is transported bound to hemoglobin (and other proteins)?
23%
84
How does the dorsal respiratory group (DRG) set the basic drive of ventilation?
It is rhythmically self excitatory (ramp signal and muscles of inspiration excitement)
85
What effect has the pneumotaxic center?
Turns off the DRG ramp signal which inhibits the duration of inspiration
86
What effect has the apneustic center?
Prevent inhibition of DRG
87
What effect has the ventral respiratory group of neurons?
Increased both inspiratory and expiratory group of muscles during increased ventilatory drive
88
What is the Herring-Breuer inflation reflex?
Inhibition of the DRG when the stretch receptors in the airways wall are activated
89
Hydrogen ions are the primary stimulus of the chemical control of ventilation, when they cross the Blood Brain Barrier (BBB)? (True/False)
False (can't cross the BBB)
90
Can CO2 cross the BBB?
Yes
91
What percentage of CO2 induced will increase ventilation at the central chemoreceptors?
70-80%
92
Is the central chemosensitive area of the respiratory center responsive to fall in oxygen?
No
93
What percentage of CO2 induced will increase ventilation at the peripheral chemoreceptors?
20-30%
94
The peripheral chemoreceptors are not sensitive to hypoxia? (True/False)
False (they are)
95
What is the effect of brain edema on ventilation?
Depression or inactivation of the respiratory centers
96
What is the O2 debt?
The extra O2 that is consumed post-exercise to replenish O2 stores and remove lactic acid
97
Pulmonic resistance decreases (elimination of hypoxia) at birth? (True/False)
True
98
What happens in acute mountain sickness?
Cerebral edema --> hypoxia & local vasodilation
| Pulmonary edema --> hypoxia & local vasoconstriction
99
What are some natural acclimatization to high altitude?
1. high ration of ventilatory capacity to body mass 2. increased size of right ventricle 3. shift in oxy-hemoglobin dissociation curve
100
Why can hyperbaric conditions (high pressure) be lethal?
Because it exposes the pulmonary capillary to extremely high blood P
101
What is the effect of high partial P of N2?
It causes narcosis (similar to alcohol intoxication)
102
What is the effect of high partial P of O2?
It leads to oxygen toxicity (seizures and free radicals damage can occur)
103
What is decompression sickness "bends"?
Nitrogen bubbles out of fluids after sudden decompression; bubbles will block blood vessels
104
The lung is ranked 3rd after the liver and the heart as an organ of body metabolism? (True/False)
False, it is ranked 2nd after the liver
105
What antibodies are involved in the immune reaction in the lung?
IgG --> lower respiratory tract
IgA --> dominate upper respiratory tract
IgE --> predominantly a mucosal antibody
