Pulmonary Physiology Flashcards

1
Q

Parasympathetic NS

A
  • Causes bronchoconstriction

- (Ach & muscarinic receptors)

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

Sympathetic NS

A
  • causes bronchodilation

- NE, Epinephrine & beta-2 receptors

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

Anatomical Dead Space

A
  • portion of tidal volue contained in conducting airways
  • doesn’t participate in gas exchange
  • reflects size of conducting airways

(approx = to body weight [108lbs=108ml)

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

2 Reasons for Physiological Dead Space

A
  • area ventilated but not perfused

- area perfused but not ventilated

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

Dead Space Types

A
  • anatomical dead space

- physiological dead space

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

Physiological dead Space

A

-the anatomic dead space plus any other areas that don’t exchange gases (that should)=alveolar dead space

=~30% of tidal volume and should be equal to anatomical dead space

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

Example of Ventilated but not Perfused

A
  • poor circulation, pulmonary embolism

- V/Q=4/0=infinity

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

Air distribution in lungs

A
  • R lung bigger=more air to it
  • dependent alveoli are more compliant and get more air
  • air goes where gravity pulls it
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Example of perfused but not ventilated

A
  • bronchospasm, obstructions, secretions, (CF, pneumonia, Asthma)
  • V/Q=0/5=0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Normal V/Q

A

4/5=0.8

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

3-Zone Model

A
  • Zone 1: least gravity dependent; gets little blood
  • Zone 2: Intermediate zone (intermittant flow based on pulmonary arterial & alveolar pressures
  • Zone 3: most gravity dependent & gets the most blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Gravity & Blood Flow

A
  • blood flow is gravity dependent

- blood flow ~6x greater at bases of lungs than apices

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

Right Ventricular Stroke Volume

A

-increased SV=increased pulmonary artery pressure & cause zone 3 to extend farther upward in each lung

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

Pulmonary Vascular Resistance

A

-increased PVR=decreased perfusion

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

Elastic Recoil

A
  • ability of lungs to return to original shape after having been stretched
  • due to elastin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

V/Q

A
  • ventilation-perfusion ratio
  • relationship between factors affecting alveolar gas flow and capillary blood flow
  • not perfectly matched: V/Q=4L/min/5L/min=0.8
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Compliance

A

-the ease with which the lungs expand during inspiration

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

low compliance=

A

greater pressure needed to get the same change in volume

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

Large compliance=

A

greater increase in volume for small change in pressure

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

Example that Increases Compliance

A

-Age & Emphysema

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

Increased Fluid in Lungs=

A

decreased compliance

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

RDS

A
  • in premature infants born before 26-28 weeks old
  • before surfactant ready

(Surfactant mature @ 35 weeks)

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

Surfactant

A
  • produced by type II alveolar cells
  • decreases H2O tension
  • decrease amount of Mm tension needed to expand lungs
24
Q

3 Factors Affecting Airway Distribution

A
  • Airway obstruction
  • Abnormal Lung or Chest wall Compliance
  • Respiratory Mm weakness
25
Examples that Decrease compliance
- fibrosis - alveolar edema - (inspiratory Mm must work harder)
26
C=
C=change in volume/change in pressure
27
WOB
-amount of muscular effort needed for ventilation -=~5% total Vo2 =~10%VC with pathology=25% VC
28
5 Factors Affecting WOB
- Airway resistance - Lung compliance - Alveolar surface tension - Dead space volume - Respiratory Rate
29
Airway Resistance
- Q(flow of air)=change in pressure/Resistance - airflow due to pressure gradient and airway resistance - radius of airway biggest control of airway resistance
30
Bronchiole Mm Control
- respond to local changes | - increased CO2 in alveolus causes vasodilatoin to increase airflow
31
Increased WOB=
-decreased tidal volume and RR-->decreased alveolar ventilation -->less O2 to blood and body
32
Assessment of Perfusion
- IV injection of technetium labeled human albumin - will lodge in pulmonary capillaries in proportion to perfusion - gamma cameras detect
33
Control mechanisms during disease
- O2 levels decreased and CO2 levels increase or stay same | - peripheral chemoreceptors fire in response to low O2 levels--><60PaO2 mmHg
34
Cold Spots
areas not ventilated or perfused
35
Assessment of Ventilation
- pt inhales radioactive xenon | - gamma camera detects location of gas in lungs
36
Diabetes
-diabetic ketoacidosis-->decreased pH (increased H+) -->firing of peripheral chemoreceptors-->increased ventilation to blow off excess acid
37
Slow-Wave Sleep
- decreased sensory stimulation - decreased central control mechanisms - decreased alveolar ventilation - PaCO2 2-3mmHg higher than waking
38
2 kinds of sleep apnea
- central | - obstructive
39
Eupnea
- normal rate and rhytm | - 12-20breaths/min
40
Tachypnea
-increased rate with normal rhythm | >20breaths/min
41
Hyperventilation
- increased rate/depth | - commonly from anxiety due to signals from cortex/limbic system that modify normal breathing
42
Apnea
-no breathing
43
Bradypnea
- decreased rate with normal rhythm | - <12 breaths/min
44
hypoventilation
shallow inspirations, often irregular
45
Kussmaul's Respiration
- deeper and faster respirations | - to compensate for metabolic/ketoacidosis (blow off excess acid/CO2)
46
Glossopharyngeal Breathing
- frog breathing | - used by high SCI injury pt to force air into lungs using tongue and palate
47
Central Sleep Apnea
- failure of respiratory center - from encephalitis, brain stem infarction, bulbar polio - idiopathic: Odine's curse-->use conscious effort to control ventilation
48
REM Sleep
- irregular breathing - decreased Mm activity-->sleep obstructive apnea -wakes person up with high PaCO2 or low O2 stimulate carotid chemoreceptors
49
Airway Receptors
- in nose, nasopharynx, larynx and trachea - respond to increased airway pressure or irritants - results in sneezing, coughing, bronchospasm or laryngospasm
50
3 respiratory reflexes
- Hering-Breuer Reflex - Juxtacapillary (J) Receptors - Airway receptors
51
Hering-Breuer Reflex
- protective receptors in smooth Mm of airways from trachea to bronchioles - when stimulated via vagus nerve to DRG to shut off inspiration - respond to lung over expansion - Tidal volume of 1.5 liter before firing
52
Juxtacapillary Receptors
- within alveolar walls near pulmonary capillaries - sense increased fluid pressure w/n caps or interstitial space - signal via vagus nerve to cause rapid shallow breathing - may be in pts with pulm edema
53
Cheyne-Stokes Respiration
- gradual increased rate and depth then slower with alternate periods of apnea - usually due t slow blood flow from heart to brain or change in feed back sensitivity to CSF - pt with cardiac failure, head injury (sign of impeding death)
54
Obstructive Sleep Apnea
- results from collapse/closure of pharynx, glottis or larynx - associated w/ obesity, hypersomnolence, hypoxemia, R heart failure, collapse of throat - most common: older men - Pickwickian Syndrome
55
Biot's Respiration
- faster and deeper respirations with abrupt pause | - often due to increased ICP