Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

SF3- EXAM 2 > Respiratory Physiology- Mechanisms I > Flashcards

Respiratory Physiology- Mechanisms I Flashcards

1
Q

Functions of the respiratory system

A
  • Exchange of gases between the atmosphere and the lung
  • Homeostatic regulation of body pH
  • Protection from inhaled pathogens/ irritants
  • Vocalization, signing, and production of audible sounds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Contraction of the diaphragm _________ (increases/decreases) thoracic volume.

A

Increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Muscles of inspiration

A

Principal

  • External intercostalis
  • Diaphragm
  • Interchondral part of internal intercostalis

Accessory

  • Seratus anterior
  • Scalene
  • Sternocleoidomasteoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Muscles of expiration

A

Active breathing

  • Internal intercostalis, except interchondral part
  • Abdominal muscles
  • Recutus abdominis
  • External oblique
  • Transversus abdominis

NOTE: There are no muscles involved in quiet expiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Functional Residual Capacity

A

The volume of air present in the lungs at the end of passive expiration.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Compliance equation

A

Change in volume/Change in pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Transpulmonary pressure

A

The difference between the alveolar pressure and the intrapleural pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

At _________ (low/high) lung volumes, large changes in transpulmonary pressure only produce small changes in lung volume.

A

High

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Emphysema results in a ____ (less/more) complaint lung.

A

More

NOTE: In emphysema, Type I alveolar cells are destroyed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pulmonary fibrosis results in a ____ (less/more) complaint lung.

A

Less

NOTE: Proliferation of connective tissue is seen here. Lungs are stiff

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which diseases result in a reduced complaince?

A
  • Pulmonary edema
  • Pleural effusion
  • Hemothorax
  • Empyema
  • Obesity
  • Musculoskeletal disease (like kyphoscoliosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Individuals with decreased compliance have to exert an increased work load for breathing. Why?

A

Becuase individials with decreased compliance must generate greater transpulmonary pressure to produce changes in the lung volume than those with normal compliance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Specific compliance

A

Demonstrates that the complaince does not change when normalized with a volume

NOTE: This is usually calculated by dividing the compliance by the functional residual capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the primary determinants of lung volumes?

A

Balanced interactions between lung and chest wall

NOTE: High recoil properties of the lung parenchyma shrink to approxiamtely 10% of TLC in the absence of chest wall. Recoil of lung parenchyma is opposed by external force of the chest wall, leading to an increase to approximately 60% of the TLC in the absence of lung parenchyma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The maximal amount of air that the lung-chest wall can hold is determined primarily by the force that can be generated by the ________.

A

Diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When does inspiratory airflow stop?

A

Once the pressure gradient is absorbed.

NOTE: Once the inspiratory muscles can no longer generate force for the movement of air, as the volume increases, the ability to stretch further decreases.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Residual volume

A

Volume of gas that remains in the lungs after maximal expiratory effort

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Functional residual capacity

A

Represents the volume of air within the lung-chest wall at a point where the two are balanced

*Each breath begins and ends at FRC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why does muscle weakness cause a reduction in FRC?

A

Becuase the lung elastic recoil exceeds the chest wall muscle force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

FRC is equal to..

A

The lung volume at which the outward recoil of the chest wall is equal to the inward elastic recoil of the lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Obstructions to airflow cause increases in FRC. Why?

A

Due to premature airway closure

REMEMBER: Each breath begins and ends with FRC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a normal RV/TLC ratio?

A

Less than 0.25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

An elevated RV/TLC ratio is seen with both obstructive and restrictive pulmonary disease. Which component of the ratio is abnormal in obstructive pulmonary disease?

A

RV is elevated. Due to air trapping 2nd to airway obstruction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

An elevated RV/TLC ratio is seen with both obstructive and restrictive pulmonary disease. Which component of the ratio is abnormal in restrictive pulmonary disease?

A

Decreased TLC.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Transmural pressure
Pressure difference between the pleural pressure and the barometric pressure
26
During inspiration, what happens to the pleural pressure?
It becomes more negative due to an increase in chest wall volume **REMEMBER:** Volume and pressure are inversely proportional
27
If alveoli pressure is greater than the baromeric pressure, air will ______ (enter/leave) the alveoli.
Leave \*pressure flows from high concentration to low concentration
28
Vital capacity
the maximum amount of air a person can expel from the lungs after a maximum inhalation
29
Vital capacity calculations
Sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume .
30
The resting volume of the chest wall is approximately ______ % of vital capacity.
60 \*Thus in the absence of the lungs the resting volume of the thorax would be approximately 60% of VC
31
Below 60% of the VC, teh chest wall has an _________ (inward/outward) elastic recoil. Above 60% of the VC, the chest wall has an ____ (inward/outward) recoil tendency.
Outward; inward **NOTE:** Above 60% of VC the chest wall has the same recoil tendency as the lungs
32
Pressure responsible for distending the lungs.
Transpulmonary pressure
33
Pressure tending to collapse the lung
Elastic recoil pressure
34
The driving pressure for expiratory gas flow
Elastic recoil pressures (PEL)
35
What is the relationship between the pressures listed below? ## Footnote **Transpulmonary pressure (PL)** **Pleural pressure (PPL)** **Alveolar pressure (PA)** **Elastic recoil pressure (PEL)**
* PA= PPL+ PEL * PL= PA-PPL * PL=PEL
36
Why does the lung volume decrease in cases of pneumothorax?
The seal is broken. So inward recoil of the lung is no longer opposed by the outward spring of the chest wall. The lung volume will decrease and the alveoli of the affected side will collapse.
37
In pneumothorax, chest wall will _________ (expand/collapse).
It will _expand_ because it is no longer opposed by inward elastic recoil of the lung parenchyma
38
When the diaphragm contracts, the thoracic volume _____ (increases/decreases)
Increases **NOTE:** This would mean that the thoracic pressure decreases
39
Surface tension
The attractive force that causes the molecules on the surface of a liquid to come together and form a layer
40
Normal surface tension for lungs
25 dyn/cm
41
Surfactant
Reduces surface tension to almost zero at the end of expiration
42
What factors contribute to the elastic properties of the lung?
Elastin Collagen Surface tension
43
Atelectasis
Collapse or closure of a lung resulting in reduced or absent gas exchange
44
Law of LaPlace
**P=2T/r** P= Pressure T= Tension r= radius According to the law of LaPlace, if two bubbles have the same surface tension, the smaller bubble will have higher pressure
45
The most abundant components in surfactant are ___ and \_\_\_\_\_\_\_\_\_\_\_.
Dipalmitoyl phosphotidylcholine Phoshotidylglygerol
46
Surfactant is secreted by _______ cells.
Alveolar Type II **NOTE:** These cells occupy aprroximately 2.7% of the alveolar gas exchanve surface area. Alveolar Type II cells are more plentiful.
47
What is the standard treatment of respiratory distress syndrome?
Surfactant replacement therapy
48
What is the importance of alveolar interpedendence?
* Increased stability of the alveoli * Collapse of one alveolus is opposed by the surrounding alveolo which help to overt atelectasis * Collateral ventilation
49
\_\_\_\_\_\_\_\_ is the resting volume of the lung and represents the point where the lung recoil and the chest wall are at equilibrium; no pressure difference across the respiratory system.
FRC
50
What is the leading cause of Chronic obstructive pulmonary disease?
Smoking
51
Symptoms of Chronic obstructive pulmonary disease
—Constant coughing, sometimes called "smoker's cough" —Shortness of breath while doing activities you used to be able to do —Excess sputum production —Feeling like you can't breathe —Not being able to take a deep breath —Wheezing
52
\_\_\_\_\_\_\_\_\_\_\_is an early diagnostic tool for COPD.
Spirometry **NOTE :** Spirometry is great for _early_ detection
53
Amount of air moving into and out of the lung during quiet respiration.
Tidal volume
54
Normal tidal volume
500 mL
55
Additional volume that you can maximally inspire beyond tidal volume
Inspiratory Reserve Volume
56
Normal Inspiratory Reserve Volume
3000 mL
57
Maximum amount of air that can be forcefully expelled at the end of a normal expiration
Expiratory Reserve Volume
58
Normale expiratory Reserve volume
1100 mL
59
Volume of air remaining in the lungs after a maximal expiratory effort
Residual volume
60
Normal residual volume
1200 mL
61
How are the following lung capacities calculated? ## Footnote **Inspiratory Capacity (IC)** **Vital Capacity (VC)** **Functional residual capacity (FRC)** **Total Lung Capacity (TLC)**
* IC= Tidal volume + Inspiratory Reserve Volume * VC= Tidal volume + Inspiratory reserve volume + Expiratory reserve volume * FRC= Residual volume + Expiratory reserve volume * TLC= Vital capacity+ Residual Volume
62
Normal Inspiratory capacity
3500 mL
63
Normal vital capacity
4600 mL
64
Normal function residual capacity
2300 mL
65
Normal TLC
5800 mL
66
Spirometry & the spirogram tracing
67
What does a plethysmography (body box) measure?
The amount of **air remaining** in teh lungs after a normal exhalation including gas that gets trapped during premature airway closure. This distorts the FRC and makes its appear _larger_ **NOTE:** The FRC would appear _lower_ when using the helium dilution technique. The two test only product similar results in **normal subjects**
68
What does the helium dilution technique measure?
The functional residual capacity of the lungs.
69
How do you calculate the lung volume using the helium dilution technique?
V2= [V1 (C1-C2)]/ [C2] ## Footnote V2= Lung Volume V1= Helium Volume C1= Helium Concentration C2= Diluted helium concentration
70
What does the nitrogen-wash out techinque measure?
The dead space of the lungs V1C1=V2C2
71
What does the effort- dependent forced vital capacity maneuver identify?
Normal, obstructive, and restrictive ventilatory disease states
72
\_\_\_\_\_\_\_\_\_\_\_\_\_ is a volume/time curve that shows the volume of exhaled air plotted against time.
Spirogram
73
What tests are reported by the spirogram?
1. The forced vital capacity (FVC); volume in liters 2. The forced expiratory volume in 1 second (FEV1). 3. The ratio of the FEV1 to the FVC (FEV1/FVC). 4. The average mid-maximal expiratory flow (MMEF) of more commonly referred to as the FEF25-75
74
How is the FVC maneuver performed?
The subject stands or sits and initially inspires to TLC while connected to a spirometer
75
What are the 3 major determinants of maximal air flow during inspiration?
* Force generated by inspiratory muscles * Increase of static recoil pressure of the lung * Airway resistance
76
When is inspiratory force greatest?
At RV, then force decreases as lung volume increases above RV
77
What are the determinants of maximal expiratory flow?
* Increases in effort (effort dependent) * Modest effort (effort independent)
78
When does maximal expiratory flow occur?
During the first 20% of the FVC maneuver
79
What are important elements of a well-performed FVE maneuver?
* Rapid Rise * Smooth decrease in expiratory flow * A decrease in flow to the baseline
80
What happens to the FEV1/FVC ratio in obstructive disease?
Decreased, due to a decrease in FEV1
81
What is PEFR?
Peak-expiratory flow (for the FVC maneuver)
82
What happens to the FEV1/FVC ratio in restrictive disease?
The ratio should be about normal or maybe slightly elevated because both the FEV1 and FVC are reduced.
83
Aside from a decrease in FEV1, what other signs are seen on spirogram of a patient with asthma or emphysema?
* High residual volume * High functional residual capacity * Low vital capacity **NOTE:** Though Bronchitis is considered an obstructive disorder, it _rarely_ cause a **high RV.**
84
\_\_\_\_\_\_\_\_\_\_\_\_ is a disease characterized by dilation of the alveolar spaces and descruction of the alveolar walls.
Emphysema **NOTE:** In cases of emphysema, compliance is increased and elasticity is decreased. So the lung becomes easy to distend but empties slowly.
85
How is the pressure gradient related to the air flow in emphysema?
Air flow is reduced in emphysema because the diaphragm is less efficient at generating pressure gradients that are necessary for breathing.
86
What are the test results of restrictive disease?
* Low TLC * Low FRC * Low RV * Normal FEV1/FVC
87
Bronchitis
A condition which is clinically defined as a chronic cough with mucus production most months of the year **NOTE:** The mucus secretions and inflammation in the bronchi tend to narrow the airways and provide an obstacle to airflow, thus increasing the resistance of the airways
88
What is a normal FEV1/FVC ratio?
90-95%
89
Why does bronchitis rarely result in a high RV?
Because the air flow obstruction found in bronchitis due to **increased resistance**, which does not generally cause the airways to collapse prematurely and trap air in the lungs.
90
What are the test results for asthma?
* Decreased maximal expiratory air flow * Decreased FVC * Decreased FEV1 * Decreased FEV1/FVC ratio **NOTE:** With asthma, significant effort is required to create an extremely negative pleural pressure
91
Characteristics of asthma
* Airway hyper-responsiveness * **Reversible increases** in bronchial smooth muscle tone * Inflammation of the bronchial mucosa * Broncho-spasm, which leads to **increased airway resistance**
92
Normal Values for Lung Volumes and Pulmonary Function mechanics
93
Lung Volume Abnormalities in Obstructive and Restrictive Pulmonary Diseases
94
Causes of Abnormal Vital Capacity
95
FRC ________ (increases/decreases) with age.
Increases \*This is associated with the decrease in elasticity
96
With age, there is a _______ (decrease/increase) in arterial tension.
Decrease \*This is as a result of ventilation-perfusion mismatch
97
Constrast the reflective events that occur early in the FVC maneuver with the events that occur late in the FVC maneuver.
**_Early_** * Large airway function * Effort dependent **_Late_** * Small airway function * Effort independent

SF3- EXAM 2 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions