RMS Quiz 1 Pulmonary Delivery

Question 1

What is cystic fibrosis characterised by

Answer 1

Thick, sticky mucus production that clogs airways and ducts and is treated using mucolytics (breaks down mucus)

Question 2

What 2 types of aerosols do we have

Answer 2

1) suspension = solid particles a suspended in air
2) solution = liquid particles suspended in air

Question 3

What does the upper respiratory tract consist of

Answer 3

Nose, throat, pharynx and larynx

Question 4

What does the lower respiratory tract consist of

Answer 4

Trachea, bronchi, bronchioles and alveoli regions

Question 5

The trachea branches into 2 bronchi, which one is wider and more likely to receive inhaled material

Answer 5

RIGHT subhnlh

Question 6

Why is it highly likely that particles will deposit on airway walls

Answer 6

Because the airways are tortuous

Question 7

What size must particles be to reach the bronchioles

Answer 7

<5 microns

Question 8

What size do particles have to be to reach the alveoli

Answer 8

<2 microns

Question 9

How many divisions are there from the trachea to the alveoli

Answer 9

23

Question 10

How does particle delivery differ in healthy vs diseased lungs

Answer 10

Particles should be less than 5 microns for delivery to healthy lungs however for diseased lungs they should be less than 3 microns approx because they’ll be more narrow

Question 11

As you further into the lungs does
a) radius
b) resistance
c) air flow speed + how would this differ for diseased lungs
Increase or decrease

Answer 11

a) increases
b) increases
c) decreases (decreases even more)

Question 12

How is aerodynamic diameter calculated, da

Answer 12

da = dg(geometric diameter) X p(density of particle)^0.5

Question 13

What are the 3 mechanism of deposition

Answer 13

1) Inertial impaction
2) sedimentation
3) Diffusion (Brownian motion)

Question 14

What’s inertial impaction

Answer 14

Particles hit the airway walls early only because they are too large (greater than 5 microns) occurs in the mouth and throat mainly

Question 15

What does inertial impaction depend on

Answer 15

Particles momentum, position and angle of bifurcation

Question 16

What’s sedimentation

Answer 16

When particles are small enough (1-5 microns) to be suspended in air through the tortuous pathway into the peripheral parts of the lung but eventually due to resistance and gravity settle in the peripheral airways

Question 17

What’s diffusion in relation to particle deposition

Answer 17

When particles are too light (less than 1 micron) to settle so they diffuse into the peripheral lung and alveoli space
They won’t settle due to gravity bc they’re too light but they eventually settle due to the Brownian motion

Question 18

How does clearance in lung occur in the upper airways (central)

Answer 18

Via mucociliary escalators = particles that deposit onto the mucus, the cilia sweep them towards the back of the throat to be swallowed and ingested
And via drug dissolution = drug dissolves and passes the thick mucus layer (less likely to occur)

Question 19

How does drug clearance in the alveolar region (peripheral) occur

Answer 19

Via macrophage clearance = macrophages engulf foreign substance and transport it to the nearest mucociliary escalators and deposit it where it is brushed up and swallowed (occurs with drugs like beclomethasone that are insoluble)

Question 20

What’s the advantages and disadvantages of local drug delivery (pulmonary)

Answer 20

Adv:
- drug delivered directly to target organ so lower doses can be administered for optimal effect
- rapid onset of action
- fewer side effects
- non invasive in this case for pulmonary delivery

Disadv:
- varying efficacy due to patients with bad inhaler technique (dependant on patients inhaler technique)
- difficult in breath coordination
- corticosteroids can suppress immune system
- throat irritation is possible from bad technique

Question 21

What are the advantages and disadvantages of systemic pulmonary drug delivery

Answer 21

Adv:
- very rapid onset of action
- circumvents first pass metabolism
- non invasive
- good for drugs that degrade easily
Disadv:
- low efficacy of delivery
- patient may find it difficult to use and thus receive no treatment benefit

Question 22

What are some challenges of pulmonary vaccines

Answer 22

The vaccine agents are unstable in aqueous environments but this may be overcome with spray-drying

Question 23

Brielfly go over the lung first and second line immune system defence

Answer 23

First line = mucus, cilia, tight junctions and surfactant
Second line = innate immune system (alveolar macrophages) & adaptive immune system (B,T cells)

Question 24

How old are a) infants, b) pre-schoolers c) school children and d) adolescents

Answer 24

a) newborn to 2 yrs b) 2-5yrs c) 5-11 yrs d) 11- 16/18 yrs

Question 25

What’s lung development like in infants

Answer 25

Alveoli are rapidly forming at this stage, they DO NOT breathe through their mouth at this time (small mouth and large tongue - can lead to breathing issues when nose is blocked), narrow airways and thus high resistance, high breathing frequency and they have laryngeal braking (controls exhalation so it isn’t prolonged too much)

Question 26

What’s lung development like in. Pre schoolers

Answer 26

Increased lung volume due to alveoli enlargement, still mostly nasal breathing (diaphragm driven), airways still narrow and have high resistance, tongue still larger than mouth and high breathing frequency

Question 27

What’s lung development like in school children

Answer 27

Girls have larger airways than boys here, airway diameter finally increases so resistance decreases, slower breathing frequency and tongue and mouth ratio decreases

Question 28

What’s lung development like in adolescence

Answer 28

Completed growth, boys airways are now larger than girls, large airways = less resistance

Question 29

What ages groups is it difficult to do lung function test

Answer 29

Infants and preschoolers

Question 30

What’s a nebuliser + advs & Disadv

Answer 30

Mist breathed suing face mask - popular for use in infants as no coordination or effort is required Adv: takes into account infants predominant nasal breathing Disadv: bulky device only available at hospitals

Question 31

What can achieve the same therapeutic outcome as a nebuliser

Answer 31

PMDI WITH a nebuliser - bc the child can breath tidally as it gives time for the droplets to evaporate BUT NOT RECOMMENDED FOR CHILDREN UNDER 4

Question 33

Can ,argue spacers be used in infants and children with small tidal volumes

Answer 33

NO

Question 34

Why is a tight seal on the nebuliser face mask important

Answer 34

A small leak can decrease aerosol delivery efficiency

Question 35

What percentage correlates to good and bad inhaler technique

Answer 35

Good = 20% Bad = 80%

Question 36

Why is paediatric inhaler design difficult

Answer 36

Inhalers are made for adults then adapted for children bc there’s a lack of clinical data (drug trials would need to be carried out on children = not ethical) and lack of paediatric deposition models