Ventilation and gas exchange Flashcards

Question

What are the results in inspiration?

Answer 1

Inspiratory muscle effort + chest refill > lung recoil

Answer 2

Chest recoil < lung recoil + expiratory muscle efforts

Answer 3

by a visceral pleural membrane

Answer 4

a parietal pleural membrane

Answer 5

* The pleural cavity (the gap between pleural membranes) is a fixed volume and contains protein-rich pleural fluid * The chest wall and lungs have their own physical properties that in combination dictate the position, characteristics and behaviour of the intact chest wall

Answer 6

Intrapleural bleeding

Answer 7

Perforated chest wall (could also be caused by a punctured lung)

Answer 8

Pressure gradients | -Normal breathing is 'negative pressure breathing'

Answer 9

-Transmural pressures (Pinside – Poutside) -A negative transrespiratory pressure will lead to inspiration -A positive transmural pressure leads to expiration

Answer 10

``` Patm = atmospheric pressure Ppl = intrapleural pressure Palv = alveolar pressure ``` ``` PTT = Transthoracic pressure PTP = Transpulmonary pressure PRS = Transrespiratory System pressure ```

Answer 11

1. The effect of the diaphragm is like a syringe - A pulling force in one direction 2. The effect of the other respiratory muscles is like a bucket handle - An upwards and outwards swinging force

Answer 12

Pressure of a gas mixture is equal to the sum (Σ) of the partial pressures (P) of gases in that mixture

Answer 13

Molecules diffuse from regions of high concentration to low concentration at a rate proportional to the concentration gradient (P1-P2), the exchange surface area (A) and the diffusion capacity (D) of the gas, and inversely proportional to the thickness of the exchange surface (T)

Answer 14

At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid

Answer 15

At a constant temperature, the volume of a gas is inversely proportional to the pressure of that gas

Answer 16

At a constant pressure, the volume of a gas is proportional to the temperature of that gas

Answer 17

WARMED, HUMIDIFIED, SLOWED and MIXED as air passes down the respiratory tree

Answer 18

16mL-min-1

Answer 19

Resting V̇O2 is approx. 250 mL·min-1 so obviously relying on dissolved oxygen alone is not conducive with life.

Answer 20

Haemoglobin monomers consist of a ferrous iron ion (Fe2+; haem- ) at the centre of a tetrapyyrole porphyrin ring connected to a protein chain (-globin); covalently bonded at the proximal histamine residue

Answer 21

Allosteric

Answer 22

As one O2 joins to haemoglobin becomes easier for other O2 to join (from tense low affinity to relaxed high affinity)

Answer 23

Greater affinity than adult HbA to ‘extract’ oxygen from mothers blood in placenta

Answer 24

Much much greater affinity than adult HbA to ‘extract’ oxygen from circulating blood and store it.

Answer 25

O2 transported in solution (~2%) or bound to Hb (~98%)

Answer 26

CO2 transported in solution, as bicarbonate (HCO3-) and as carbamino compounds (e.g. HbCO2)

Answer 27

sigmoid shaped

Answer 28

is almost linear

Answer 29

1. Decrease temp 2. Alkalosis 3. Hypocapnia 4. Decrease 2,3 DPG ↑pH, ↓PCO2, ↓temp and ↓2,3-DPG (= Increased affinity as O2 binds at a lower pO2)

Answer 30

1. Increased temperature 2. Acidosis 3. Hypercapnia 4. Higher 2,3 DPG ↓pH, ↑PCO2, ↑temp and ↑2,3-DPG (Bohr effect)

Answer 31

polycythaemia

Answer 32

VVVV greater affinity than adult haemoglobin to extract oxygen from circulating blood and store it

Answer 33

- When the PO2 is low is when O2 is off-loaded and when Hb has a lower affinity of the O2 - But once the first O2 binds then the others bind easier - When the PO2 is high is when O2 is taken up by Hb

Ventilation and gas exchange Flashcards

(58 cards)