Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

B2W2 > Ventilation and Lung Volumes Gas Transport > Flashcards

Ventilation and Lung Volumes Gas Transport Flashcards

1
Q

How do you calculate Tidal volume?

A

Tidal volume is dead space + volume of air entering alveoli.

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

How do we calculate pulmonary ventilation?

A

Pulmonary ventilation is respiratory rate x tidal volume (RR x TV)

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

How do we calculate the alveolar ventilation?

A

RR X (TV-DS) (minus the dead space, usually about 150ml)

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

What is minute volume?

A

The volume of air entering and leaving the lungs each minute (or pulmonary ventilation)

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

What is Tidal volume?

A

The air taken in and out with each breath

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

How are respiration rates varied throughout life?

A

Newborn - 30-60 breaths ber minute

Young Children - 20-30 breaths per minute

Adults - 12-20 breaths per minute

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

How do you work out minute volume?

A

MV = Respiratory Rate (RR) x Tidal Volume (TV)

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

At what point does conducting airways become respiratory airways?

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

Ventilation is classified as…

A

Pulmonary ventilation = moving gases in/out of lungs

Alveolar ventilation = volume of air participates in gas exchange

So alveolar ventilation is less than pulmonary ventilation

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

Why is alveolar ventilation less in volume than pulmonary ventilation?

A

Because not all the air that’s in the lungs gets exchanged.

This is called ‘dead space’

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

What are the two types of dead space?

A

Anatomical dead space

Physiological dead space - is the part of the respiratory system where gaseous exchange

Generally speaking in normal the dead space volume is about the same in both components.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How would you calculate tidal volume?

A

Tidal volume = dead space + volume of air entering alveoli

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

Label the parts of the Spirometer

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

Label the parts of a Spirogram.

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

What makes up the functional residual capacity?

A

The expiratory reserve volume + residual volume

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

What are the typical lung volume capacities?

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

What is inspiratory capacity?

A

Tidal volume + inspiratory reserve volume

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

What’s the functional residual capacity?

A

expiratory reserve volume + reserve volume

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

How can residual volume and functional residual capacity be measured?

A
  • They cannot be measured by spirometry.
  • They helium hilution method or plethysmography are used instead.

-

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

What is the helium dilution method?

A
  1. Get them to first breathe normally until reaching equilibrium
  2. Then something or other
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens to residual volume and forced viral capacity in diseased states?

A
  • Increased RV occurs in emphysema and COPD and sometimes in asthma
  • Respiratory muscles have a greater resting length
  • Respiratory movements are less efficient
  • Work of breahting is increased
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the tests of ventilatory function?

A

In respiratory diseases it is important to measure degree to which airflow is limited.

A couples of useful measures are:

Forced expiratory volume in 1 second (FEV1 ) and Forced Vital Capacity (FVC) and its ratio FEV1/FVC is expresses as a %.

FEV1 and FVC are measured against predictive values.

Peak Expiratory Flow Rate (PEFR) also used: PEFR is a person’s maximum speed of expiration as measured with a peak flow meter

A good way to monitor COPD/Asthma is to monitor at home.

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

How would time-volime graph be different in obstruction and restriction?

A
24
Q

What is a flow volume loop?

A

The flow-volume loop (also called a spirogram) is a plot of the inspiratory and expiratory flow (on the Y axis) against volume (X axis) during the performance of maximally forced inspiratory and expiratory maneuvers.

25
Q

What moves oxygen into blood and Co2 into air from blood?

A

Pressure gradient

  • Negative intrathoracic pressure –> ventilation (breathe in, volume gets bigger, pressure drop in lungs, becomes sub-atmospheric, air rushes in)
  • Partial pressure differences (in alveoli, oxygen leaves, co2 is low in inspired air, so co2 leaves)
26
Q

What is Boyl’es law?

A

A law stating that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature.

27
Q

What is Avogadro’s Law?

A

Volume of gas at the same temperature & pressure contain the same number of molecules

28
Q

What is Charle’s Law?

A

At a constant pressure the volume of gass is proportional to its absolute temperature

29
Q

What is the ideal gas law?

A

The volume occupied by n moles of any gas has a pressure (P) at temperature (T).

PV = nRT

P × V = n × (R) × T,

30
Q

What are the Graham and Henry’s law of gases?

A
31
Q

Give an overview of Dalton’s Law of partial pressure

A

The Pressure exerted by a mixutre of gases is equal to the sum of the individual partial pressure exerted by each gas in the same volume.

E.g. in alveoli

PB = pn2 + po2+ pc02 + p520

Ph20 = water vapour pressure

32
Q

What is the partial pressure of O2 in air?

A

Air contains 21% O2

PiO2 = partial pressure of inspired O2

in mmHG = 21% of 760 = 159

in kPa = 21% of 101 = 21

33
Q

What is the difference in pressure of atmospheric air vs alveolar air?

A
34
Q

What does the rate of diffusion of O2 and Co2 from aqueous lining of alveoli to blood depend on?

A
  • The partial pressure of the gas
  • The solubility of the gas in the liquid: solubility of Co2 > x20 of O2
  • Area available for gas exchange
  • Thickness of alveolar membrane

Ability of gas to diffuse betwen alveolar air and blood is measured by its diffusing capacity (or transfer factor) DL

35
Q

Describe the ultrastructure of the respiratory membrane

A
  • Gaseous exchange due to pressure differences
36
Q

Give some facts about oxugen exchange

A
  • Dissolves slightly in H20
  • Forms a reversible combination with Hb
  • The amount of O2 carried by the blood can be expressed as:
    1) Arterial oxygen content CaO2 (ml/100ml)
    2) The arterial oxuygen content (CaO2) is the amount of oxygen bound to Hb + the amount of oxygen dissolved in arterial blood
  • % saturation of Hb with O2, SaO2 (%)
  • The relationship of PaO2 to SaO2 and CaO2 is not linear.
  • It is the O2 dissociation curve for Hb
37
Q

Explain the diffusion gradient from the capillaries to the alveoli and the tissues

A
38
Q

Describe the structure of haemoglobin

A
  • 1 molecule of oxygen binds 4 oxygen molecules
  • Each heme group has a porphyrin ring with an iron atom in the center
  • Fetal haemoglobin is slightly different (2 alpha and 2 gamma globulin chains)
39
Q

Explain Haemoglobin & Oxygen transport

A
40
Q

Explain the haemoglobin-oxygen dissociation curve

A
41
Q

What is the haemoglobin-oxygen dissociation curve?

A
42
Q

What would happen if the oxygen-haemoglobin curve shifted to the left?

A

Hb’s O2 affinity increases and the Hb-O2 dissociation curve shift lefts when there is a decrease in

  • body temperature
  • PCO2

[2,3-BPG}

[H+} an increase in pH

43
Q

Explan the differences seen in the foetal and adult HbO2 dissociation curves

A
  • Higher affinity for oxygen
  • So adult can give off oxygen to fetal blood supply via placenta
44
Q

What are the dangers of carbon monoxide?

A

CO binds stronger than O2

45
Q

How is CO2 transported in the blood?

A
46
Q

Explain the Co2 Dissociation Curve

A

Haldane Effect: removing O2 from Hb incrfeases ability of Hb to pick up CO2 and CO2 generated H+

The Bohr effect and the Haldane effect work in synchrony to facilitate: O2 liberation and uptake of CO2 & Co2 generated H+ at tissues

47
Q

Explain gas exchange a thte tissues

A

Haemoglobin binds to H+ ions causing chloride shift

48
Q

Explain gas exchange in the lungs

A
49
Q

What is the acid-base balance?

A
50
Q

What is the principal equation?

A
51
Q

What is the Henderson-Hasselbalch Equation?

A
52
Q

What are the causes of pH changes in the blood?

A

Respiratory

Hypoventilation –> Acidosis

Hyperventilation –> Alkalosis

Metabolic (including renal)

  • Diabetic Ketoacidosis –> acidosis

Vomiting - Alkalosis

  • Renal failure - Acidosis
53
Q

What are the Physiological responses to pH changes?

A
  • Buffering by chemicals, including HCO3-, Hb and other blood proteins (rapid response, limited capacity)
  • Changes in ventilation (rapid response, impossible if primary cause is respiratory)
  • Changes in renal excretion of H+ and HCO3- (slower response, limited if the -primary cause is renal)
54
Q

What happens in respiratory acidosis?

A
  • Lungs retain Co2
  • HCO3- rises and pH falls
  • Kidney compensates by retaining HCO3- and excreting H+ (slow)
  • This resotres pH towards normal
  • But HCO3- and PCo2 remain high
55
Q

What happens in respiratory alkalosis?

A
  • Lungs lose excess Co2
  • HCO3- falls and pH rises
  • Kidney compensated by retaining H+ and excreting HCO3- (slow)
  • This restores pH towards normal
  • But HCO3- and PCO2 remain low
56
Q

What is a davenport diagram?

A

B2W2 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions