drug delivery to the lungs

Question 1

what does the anatomical structure of the airway prevent

Answer 1

the entry of and promotes the removal of airborne foreign particles (including microorganisms)

Question 2

what does branching in the lungs cause

Answer 2

turbulent air flow in upper conduction zone during inspiration

Question 3

what are the conducting airways from the trachea to the bronchi lined with

Answer 3

ciliated epithelial cells and goblet cells which secrete mucous to trap and remove foreign particles

Question 4

what are aerosols

Answer 4

solid or liquid particles dispersed in a gaseous phase

Question 5

when would pulmonary administration of drugs be used

Answer 5

for treatment of localised disorders eg asthma, copd

Question 6

advantages of pulmonary administration of drugs

Answer 6

• good for systemic delivery of drugs due to high SA
• well perfused tissue
• avoids first pass metabolism

Question 7

what factors affect disposition

Answer 7

• physiochem properties
• formulation
• delivery device
• patient factors

Question 8

when does the diameter of the conductive airway start to decrease

Answer 8

towards the alveoli

Question 9

when does aerosol particle size become fundamentally important

Answer 9

in where it is deposited within airway

Question 10

what is referred to in terms of aerodynamic diameter (Da)

Answer 10

size

Question 11

will porous particles have a smaller apparent aerodynamic diameter or larger

Answer 11

smaller

Question 12

calc for aerodynamic diameter

Answer 12

da = (P/P0)^0.5 X dp

p=density of particle
p0=density of spherical particle
dp= diameter of particle

Question 13

how can the porosity of a particle be manipulated

Answer 13

• choice of excipients
• formulation process

Question 14

why is dry powder inhaler material most used

Answer 14

its good for lung environment and gentle on lung proteins

Question 15

what can high humidity in resp tract result in

Answer 15

interaction with aerosol particle and change resultant aerodynamics

Question 16

where do larger particles deposit within the resp tract

Answer 16

higher within the tract, may impact upon clinical performance

Question 17

is aerosol deposition negligible or considerable with hydrophobic surfaces

Answer 17

negligable

Question 18

is aerosol deposition negligible or considerable with hydrophilic surfaces

Answer 18

considerable

Question 19

how long after first inhalation of tobacco smoke can nicotine be found in the brain

Answer 19

5-10 seconds after

Question 20

what can fast rate of rise of nicotine in brain contribute to

Answer 20

nicotine dependence in smokers

Question 21

what happens when you smoke in terms to nicotine (steps)

Answer 21

1. it moves to lungs, absorbed into bloodstream
2. heart pumps it through body, including brain
3. nicotine moves from blood to brain easily

Question 22

how quick is the decline of nicotine in brain

Answer 22

rapid with half-life of one hour

Question 23

examples of smoking cessation treatments that can be offered

Answer 23

• patches
• chewing gums
• sprays
• inhaler

Question 24

what effects does cigarette smoke have on the heart and lungs

Answer 24

• inflammation
• oxidative stress

Question 25

what effects does cigarette smoke have on the liver

Answer 25

releases fibrinogen, factor VIII

causes endothelial activation and dysfunction