Exam 3 Pulmonary Physiology Flashcards
1
Q
What are the inspiratory muscles?
A
Diaphragm, external intercostals, SCM,anterior serratus, scalenes and levator costarum
2
Q
What are the expiratory muscles?
A
Abdominals, internal intercostals, post inferior. Serratus, transverse thoracis, Pyramidal
3
Q
What is the only muscle during inspiration doesn’t lift the rib cage?
A
Diaphragm, which drops the floor of the thoracic cage
4
Q
Which muscle of expiration is involved in low back pain?
A
Transverse abdominis
5
Q
During what conditions is expiration passive and associated with recoil of the lungs?
A
Resting conditions
6
Q
What is pleural pressure?
A
Negative pressure between parietal and visceral pleura which keeps lung inflated against chest wall
Various between -5 to -7.5 cmH20
7
Q
What are the two different kinds of alveolar pressure?
A
Sub Atmospheric and supra-atmospheric
8
Q
Which alveolar pressure is associated with inspiration
A
Subatmospheric
9
Q
What alveolar pressure is associated with expiration
A
Supra-atmospheric
10
Q
What is transpulmonary pressure?
A
The difference between alveolar P and pleural P
11
Q
What measures the recoil tendency of the lung and peaks at the end of inspiration_____________.
A
Transpulmonary pressure
12
Q
True or False
At the onset of inspiration the pleural pressure changes at a faster rate than lung volume?
A
True
Known as “hysteresis” phenomenon
13
Q
Which lung is easier to inflate a saline or air filled one?
A
Saline because surface tension is gone
14
Q
What overrides the natural recoil tendency of the lung?
A
Expansion of the thoracic cage resulting in an increase of lung volume
15
Q
What is Eupnea
A
Normal breathing 12-17 B/min 500-600 ml
Arterial CO2= 40mmHg
16
Q
What is Hyperpnea
A
Increase in pulmonary ventilating matching metabolic demand
Arterial CO2= 40mmHg
17
Q
What is happening during hyperventilation
A
Increase in pulmonary ventilation greater than metabolic demand
Arterial CO2 decreases to less than 40mmHg
18
Q
What occurs during hypoventilation
A
Pulmonary ventilation lower than metabolic demand
Increase in Arterial CO2 greater than 40 mmHg
19
Q
What is Tachypnea
A
Increase in the frequency of respiratory rate
20
Q
What is apnea?
A
Absence of breathing
Ex. Sleep apnea
21
Q
What is Dyspnea
A
Difficult or labored breathing
22
Q
What is Orthopnea
A
Dyspnea when recumbent, relieved when upright
Ex. Congestive heart failure, asthma, lung failure
23
Q
True or False
Lungs have a natural tendency to collapse
A
True
Surface tension forces 2/3
Elastic Fibers 1/3
24
Q
What keeps lungs against the chest wall
A
By negative pleural pressure “suction”
25
True or False
If the pleural P= atmospheric P the lung will collapse?
True
Examples
Puncture of parietal pleural
Erosion of visceral pleura
If a major airway is blocked the air trapped distal to the block will be absorbed by the blood and that segment of the lung will collapse
26
What is Pleural fluid?
Thin layer of mucous fluid
Provides lubrication
Transudate ( interstitial fluid + protein)
Total amount is only a few ml's
27
What happens to excess of pleural fluid?
Is removed by lymphatics
- mediastinum
- superior surface of diaphragm
- lateral surfaces of parietal pleural
- helps create negative pleural pressure
28
What is a pleural effusion?
Collection of large amounts of free fluid in pleural space.
Edema of pleural cavity
29
What are the causes of pleural effusion?
Blockage of lymphatic drainage
Cardiac failure- increased capillary filtration P
Reduced plasma colloid osmotic pressure
Infection/inflammation of pleural surfaces which breaks down capillary membranes
30
What is surfactant?
Reduces surface tension forces by forming a mono molecular layer between aqueous fluid lining the alveoli and air, preventing a water-air interface
31
Surfactant is produced by ________________. It consists of _________________________.
Type II alveolar epithelial cells. Dipalmitoyl lecithin, surfactant apoproteins, Ca++ ions
32
What is the Law of Laplace?
P=2T/r
Without surfactant smaller alveolar have increased collapse P and tend to empty into larger alveoli
AKA big would get bigger and small would get smaller
33
Role of surfactant??
As alveolar size decreases the surfactant is concentrated which decreases surface tension forces, of setting the decrease in radius of a smaller cell
34
What is interdependence?
Size of one alveoli determined in part by surrounding alveoli
35
What is tidal volume
Amount of air moved in or out each breath
500ml
36
What is inspiratory reserve volume?
Maximum volume one can inspire above normal inspiration
3000ml
37
What is expiratory reserve volume
Maximum volume one can expire below normal expiration
1100ml
38
This is the volume of air left in the lungs after maximum expiratory effort
residual volume
1200ml
39
This is the volume of air left in the lungs after a normal expiration, balance point of lung recoil and chest wall forces
Functional residual capacity (RV+ERV)
40
Maximum volume one can inspire during an inspiration effort
Inspiratory capacity (TV+IRV)
41
max volume one can exchange in a respiratory cycle
Vital capacity (IRV+TV+ERV)
42
The air in the lungs at full inflation is called _________________
Total lung capacity (IRV+TV+ERV+RV)
43
What lung volumes cant be determined by basic Spirometry?
RV, FRC, TLC
Must use helium dilution method for these
44
How do you find RV?
RV=FRC-ERV
45
How do you find TLC?
TLC=RV+VC
46
How many generations of branching is there in the lungs?
20
47
How many generations of branching are there in the bronchi?
First 11 generations of branching
48
How many generations of branching are in the bronchioles
Next 5 generations after bronchi
49
How many generations of branching are in respiratory bronchioles
Last 4 generations of branching
50
Where can gas exchange cannot occur?
Dead space
51
SNS beta receptors cause __________
Dilation due mainly to indirect effect via circulating epinephrine
52
Parasympathetic muscarinic receptors cause______________
Constriction
53
NANC nerve (non adrenergic, non cholinergic) due what?
Inhibitory release VIP and NO= bronchodialtion
Stimulatory= bronchoconstriction, mucous secretion, vascular hyperpermeability, cough, vasodilation, "neurogenic inflammation"
54
What are the two types of adapting receptors of afferent nerves?
Slow adapting receptors and rapidly adapting receptors
55
What are slow adapting receptors?
Associated with smooth muscle of proximal airways
Stretch receptors- involved in reflex control of breathing and cough reflex
56
What are rapidly adapting receptors?
Sensitive to mechanical +, protons, low Cl solutions, histamine, cigarette smoke, ozone, serotonin, PGF2
57
what are C fibers
They are high density fibers that contain neuropeptides ex. Substance P, neurokinin A, calcitonin gene related peptide
Selectively + by capsaicin
58
What happens when histamine binds to H1 receptors?
Constriction
59
What happens when histamine binds to H2 receptors
Dilation
60
Slow reactive substance of anaphylaxisis causes?
Constriction- allergic response to pollen
61
What do prostaglandins E series do?
Dilation
62
Prostaglandins F series do?
Constriction
63
Environmental pollution results in _______________. Which is mediated by ___________ and ________________.
Constriction
Parasympathetic reflex and local constrictor response
64
What is the normal level of HCO3?
Metabolic acidosis levels?
Metabolic alkalosis levels?
24 mEq/L
Acidosis HCO324 will decrease ventilation
65
What regulations HCO3 levels?
Kidneys
66
What is the normal level of CO2?
Respiratory acidosis?
Respiratory alkalosis?
40mmHg
Acidosis CO2>40 + ventilation
Alkalosis CO2
67
What regulates CO2?
Lung
68
All pulmonary arteries have ____________
Larger lumen
More compliant
Operate under a lower pressure
Can accommodate 2/3 of SV from RV
69
What is the total amount of Pulmonic blood volume?
450 ml (9% of total blood volume)
70
True or False
Shifts in volume can occur from pulmonic to systemic or vice versa
True
71
What can cause an increase of pulmonary volume of 100%?
Mitral stenosis
72
True or False
Shifts have a greater effect on pulmonary circulation?
True
73
Venous drainage is into the azygous (1/2) or pulmonary veins (1/2) (short circuit)
True or false
True
74
True or False
The lung is the only organ to receive blood flow in excess of cardiac output because it receives both total pulmonic flow and some systemic flow simultaneously
True
75
What is the Total blood flow to the lungs?
Right ventricular output + bronchial artery flow
76
Which lung does most of the lymphatic tissue drain into?
The right lung
77
What helps create the "respiratory membrane"?
Pulmonary lymphatics, helps maintain negative interstitial pressure which pulls alveolar epithelium against capillary edothelium
78
What is the range of pulmonary artery pressure?
8-25
Mean 15mmhg
79
What is the mean P of pulmonary capillaries
7 mmHg
80
What is the P of major pulmonary veins and left atrium?
Mean P 2 mmHg
81
True or False
If low alveolar O2 is present it causes release of a local vasoconstrictor which automatically redistributes blood to better ventilated areas
True
82
SNS will cause mild __________________, mediated by __________________.
vasoconstriction, alpha receptors.
However once 30Hz is reached vasodilation is observed as beta receptors are unmasked
83
Parasympathetic Increase will cause __________
Mild vasodilation
84
What is a major constrictor on pulmonary vascular smooth muscle is _______________
Low alveolar 02
85
Under resting conditions blood is fully oxygenated by the time it has passed _______ of pulmonary capillaries.
1/3
86
What is the limiting factor of oxygenation of pulmonary capillaries in exercise
SV
87
What are the effects of hydrostatic P on regional pulmonary blood flow?
Zone 1- no flow, alveolar P> capillary P
Zone 2- intermittent flow, during systole= capillary P> alveolar P. During diastole= alveolar P> capillary P
Zone 3- continuous flow, capillary P> alveolar P towards base of lung
88
What cause the entire lung to enter the 3rd zone of pulmonary blood flow
Exercise!!!! Capillary P>alveolar P
89
Pulmonary Capillary dynamics results in______
Net forces favoring filtration by 1mmHg. The excess fluid removed by lymphatics
90
At a constant T and V of a given quantity of gas is 1/x to the P it exerts
Boyle' Law
91
V of gas at the same T and P contain the same # of molecules
Avogadro's Law
92
At a constant P and V of a gas is x to its absolute T
Charles Law
93
The rate of diffusion of a gas is 1/x to the square root of its molecular weight?
Grahams Law
94
The quantity of gas that can dissolve in a fluid is = to the partial P of the gas X the solubility coefficient
Henry's Law
95
The P exerted by a mixture of gases is = Energy of the individual (partial) P exerted by each gas
Daltons Law of Parital Pressures
96
At body temperature the vapor P of H2O is _________
47 mmHg
97
What are the alveoli averages for CO2 and O2?
CO2= 40 mmHG
O2= 104 mmHg
98
The respiratory unit contains ___________ alveoli and consists of what two layers?
300 million
Alveolar epithelium, capillary endothelium
99
What diffuses at least 20x more readily than oxygen?
Carbon Dioxide
100
During expiration what happens to the air?
O2 falls from 159 to 104 mmHg
CO2 rises from 0 to 40 mmHg
1st 100 ml of air is from dead space
Last 250 ml of expired air is alveolar air the rest is a mix
101
How many breaths does it take to have a complete turnover of alveolar air?
6-7 breaths
Slow turnover prevents large changes in gas concentration in alveoli from breath to breath
102
True of False
Normally alveolar ventilation is matched to pulmonary capillary perfusion at a rate of 4L/min of air to 5L/min of blood
True
This means the V/P ratio is 4/5
103
If the ventilation-Perfusion ratio decreases then it is due to a problem resulting in __________
Decreased ventilation
104
IF the ventilation -Perfusion ratio increases it is a result from
Decreased perfusion of the lungs
105
A physiologic shunt blood is __________
Blood that is not oxygenated as it passes the lung due to the decreased V/P ratio
106
A increased V/P ratio due to a decreased perfusion of the lungs from the RV results in _____________
Alveolar PO2 increases to 149 mmHg
Alveolar PCO2 will decrease toward ) mmHg
RESULTS IN AN INCREASE IN PHYSIOLOGIC DEAD SPACE
107
When fatty acid utilization for E increases the percentage of metabolic water generated from O2 increases up to _________
30%
108
If only CHO is used for energy no metabolic water is generated from all the all the O2 is converted to _____
CO2
109
As PO2 decreases hemoglobin ____________
Releases more oxygen
110
A shift to the right of a sigmoid curve indicates ____________
Dissociation of Oxygen from hemoglobin
111
Carbon dioxide is carried most commonly in what form in the body at about 70%
bicarbonate
112
What percentage of CO2 is bound to hemoglobin?
23%
113
Dissolved CO2 in the blood is what percent
7%
114
Carbon monoxide is ______ higher affinity than oxygen in hemoglobin?
250x
115
Pco= .4mmHg will saturate 97% of hemoglobin which can decrease carry capacity by ________?
50%
116
What concentration can CO be lethal?
.1% aka Pco= .6mmHg
117
Is CO produced by the body?
True or False
True
118
What are the functions of physiologic CO?
Signaling molecule in nervous system
Vasodilator
important role in immune,respiratory, GI, kidney and liver systems
119
What sets the basic drive of ventilation?
Dorsal respiratory group
120
Where is the dorsal respiratory group located?
Primarily in nucleus tracts solitarius in medulla terminate CN IX and X.
Excites muscles of inspiration
121
What does the Pneumotaxic center do?
Located in the N. Parabrachialis of upper pons and inhibits the duration of inspiration by turning off DRG
122
Where is the ventral respiratory group of neurons located?
Bilaterally in ventral aspect of medulla
123
What do ventral respiratory group of neurons do?
Can increase both inspiratory and expiratory respiratory muscles during increased ventilators drive
124
What does the Apneustic center do?
Functions to prevent inhibition of DRG under some circumstances
125
What is the Herring Breuer inflation reflex/
Stretch receptors located in the wall of airways inhibit DRG when tidal volumes exceed 1500 ml
126
What are irritant receptors?
Inhibit and increase sneezing and coughing and possible airway constriction
127
What are J receptors?
Located in alveoli next to pulmonary caps
Increase when pulmonary caps are engorged or pulmonary edema
*create feeling of dyspnea*
128
True or False
Carbon dioxide and hydrogen ions can cross BBB
False, only Carbon dioxide can cross BBB
129
When CO2 concentrations increase in CSF they __________ ventilation
Increase
130
What are Peripheral chemoreceptors found and what are they responsive too?
Aortic and carotid bodies, respond to hypoxia
131
What happens to respiratory centers when brain edema occurs and how to treat it?
Respiratory centers are depressed, and treatment is mannitol
132
What is the most prevalent cause of respiratory depression?
Narcotics
Ex. Sodium pentobarbital and morphine
133
How much stored O2 is in the body for aerobic metabolism?
2L
.5L in lungs
.25L in body fluids
1L in combined with hemoglobin
.3 in muscle myoglobin
134
Heavy exercise how quickly is the stored O2 used up in?
2 mins
The O2 debt can reach 11.5 L
135
What is Alactacid oxygen debt?
Is about 3.5L is replenished within the first couple minutes of post exercise
136
What is Lactic acid oxygen debt?
8L total is changed over the first 40 minutes of poster exercise and helps remove lactic acid
137
How much pressure does it take to have first breath as a baby?
40-60 cm H2O of negative pleural P
138
During birth what closes?
Foramen ovale
Ductus arteriosis
Ductus venosus
139
True or False
At 63,000 ft the barometric P is 47 mmHg and blood "boils"
True
140
During acute mountain sickness what is the difference between cerebral edema and pulmonary edema?
Both end up in hypoxia.
Pulmonary edema= local vasoconstriction
Cerebral edema= local vasodilation
141
An increase in ph is inhibitory to ventilation and opposes the increase effects of hypoxia on peripheral chemoreceptors
True or False
True
142
Chronic mountain sickness can result in _________ if person is not removed to a lower altitude
Death
143
Acclimatization results in
Increase in RBC
Increase in diffusion capacity of lungs
Increase of tissue vascularity
Increase of ability of tissue to use O2
Increased synthesis of 2,3 DPG shifts curve to the right
144
What altitude do you have to be at for natural acclimatization to occur?
13,000 ft
145
What is hyperbarism?
When the lungs are exposed to extremely high alveolar gas pressures which can be lethal
146
Effect of N high partial pressures are?
120ft- joviality, carefree
150-200 drowsiness
200-250 weakness
250- unable to function lose consciousness
Similar to alcohol intoxication
147
What are the effects of high partial pressure?
Oxygen toxicity, siezures and coma within 30-60 mins
This occurs above 2 atmospheres
148
What is decompression sickness aka Bends?
Nitrogen bubbles out of fluids after sudden decompression
Symptoms- pain in joints, dizziness, "the chokes"
149
True or False the lung ranks second behind the liver in metabolism?
True
150
When Angiotensin I is passed through the lung is is converted to ________
Angiotensin II
151
True or False
Prostaglandins inactivated in one pass through pulmonary circulation?
True
152
How much air does the average adult inhale?
10,000 L
153
What do long hairs in the nose do?
Filters out larger particles
154
What does mucous coating in the nose do?
Traps particles bigger than 10 microns, moisten air 650 ml H20/day
155
What do nasal turbinates do?
Highly vascularized, act as radiators to warm air
156
Stats about coughing?
Afferents utilize primarily CN X
2.5L of air rapidly inspired
Lung pressure rises to 100mmHg
157
How is sneeze reflex used?
Irritation sends signal over CN V to the medulla
158
What does the mucociliary elevator do?
Clears smaller airways
Moves the mucous to the pharynx which beat 1000x/min
159
What are alveolar marcrophages called/do?
Dust cells
Capable of phagocytosis intraluminal particles
Principal phagocytes cells in the distal air spaces
160
What is the complement system?
Small proteins found in the blood to synthesize in the liver
Part of the innate immune system
161
What are the three antibodies in the lung?
IgG- lower respiratory tract
IgA- dominate in upper respiratory tract
IgE- predominantly a mucosal antibody
162
What is the humoral immune system?
Antibodies, accessory processes, made up of various lipoproteins and glycoproteins
