Respiratory system Flashcards
Exam 1
What is the pathology of asthma?
A narrow lumen in people with asthma which means air restriction flow
An increase in goblet cells (hyperplasia) so more mucus is secreted
Smooth muscle is thicker and increase in blood vessels which have oedema and become leaky
An increase in collagen makes it thicker
What is the early phase of asthma?
– Hypersensitivity
– Spasm of airways smooth muscle
– Hyper secretion of mucus
– Bronchoconstriction
What is the late phase of asthma?
– Cellular infiltration – injury of airway epithelium – hypersensitivity – loss of ciliary function –bronchoconstriction
What are the symptoms of asthma?
– Wheezing (especially on expiration)
– Breathlessness (not enough O2)
– Coughing
– Chest tightness
What is bronchitis?
Inflammation of bronchioles
What is emphysema?
The membranes in the alveoli which hold them are broken down which leads to large holes in air spaces
Not efficient gas exchange
What are symptoms of chronic bronchitis?
– Excess mucus production – bronchospasm – wheezing dyspnea – hypoxia and hypercapnia – productive cough – overweight
What are the symptoms of emphysema?
– Increase dyspnoea even at rest – Minimal cough – hyperventilation – thin pursed lips to compensate for lack of elastic recoil
What does hyperplasia mean?
An enlargement due to the increase in production of cells
What does hyper trophy mean?
An enlargement due to the cell size increase
Why is there an increase in luminal mucus with asthma and COPD?
Goblet cells hyperplasia and metaplasia
Submucosal gland hyper trophy
What is the name given when cilia can’t clear mucus?
Abnormal mucociliary clearance
Is it common to have COPD if under 35?
No it is rare
Is a chronic productive cough present in asthma symptoms?
No more of a dry cough
Where are the guidelines for asthma treatment and diagnosis?
BTS/ SIGN 2019
Where are the guidelines for COPD treatment and diagnosis?
NICE NG115
What does atopic history mean?
Strong links with other allergies for example eczema
What can be some triggers of asthma?
Allergen exposure, infection, cold air, exercise, some medication (NSAID’s)
What is included in a high diagnosis probability of asthma?
Typical symptoms, wheeze, no suggestion of alternative
Record likely asthma, start treatment for six weeks with inhaled corticosteroid reassess symptoms
What is included in a medium diagnosis probability of asthma?
Some but not all typical features or do not respond to initial treatment
Carry out reversibility test with Bronco dilator repeat after ICS
What is peak expiratory flow and give the benefits?
Measurement of volume of air expelled from lungs
Cheap and easy to use
Can keep a diary
Useful diagnosis and monitoring
Give red flags in asthma diagnosis:
– Unexpected clinical features (crackles)
– Persistent breathlessness
– X-ray shows shadows
– Chronic sputum production
If over 35, what other symptoms are likely to be COPD?
- Excertional breathlessness
- Chronic cough
- Regular sputum production
- Freq winter bronchitis
- Wheeze
What are two red flag symptoms of COPD?
Chest pain and haemoptysis- coughing up blood
What is a dyspnoea scale?
Scale from grade 1 to 5, one being the least and five being the most
What is spirometry?
Monitors lung function and diagnosis respiratory conditions
Measured expelled from lungs by mouth, not nose (sealed)
What is a normal forced expiratory volume compared to one of asthma?
Normal 4 litres
Asthma 2 litres
Before changing asthma treatment, what are three things to check?
- Adherence
- Inhaler techniques
- Eliminate triggers
What is an SABA?
Short acting B2 agonist (salbutamol)
Releiver
What is an LABA?
Long acting B2 agonist (salmeterol)
What is an ICS?
Inhaled corticosteroids (beclomethasone) Preventer
What is an LTRA?
Leukotriene receptor antagonists (Montelukast)
What is MART?
Maintenance and reliever therapy (LABA+ ICS)
What is a SAMA?
Short acting muscarinic antagonists (Ipratropium)
What is a LAMA?
Long acting muscarinic antagonists (Tiotropium)
What is the basic first treatment of asthma?
ICS
What do you add to the first treatment of asthma if it doesn’t work?
Inhaled LABA
What are three nonpharmaceutical treatments for COPD?
– Treatment and support to stop smoking
– Pneumonnical and influenza vaccines
– Pulmonary rehabilitation (physiotherapist)
What pharmaceutical treatment should be used for COPD if the patient also has asthma symptoms?
LABA+ ICS
What pharmaceutical treatment should be used for COPD if the patient doesn’t have asthma symptoms?
LABA+ LAMA
What if there is no improvement on the second stage of treatment for COPD?
Use LABA, LAMA and ICS
Name the five inhaled corticosteroids:
Beclometasone
Budsonide
Fluticasone
Ciclesonide
Mometasone
Last two only licensed for asthma as they’re single ingredient inhalers
What are the other formulations of corticosteroids and their use?
Nasal spray- allergic rhinitis
Topical creams/ ointments- eczema
What are the two brands beclometasone is available in?
Qvar
Clenil
Are the two brands of beclometasone interchangeable and why?
No, must be prescribed by brand and not generic name
Qvar has extra fine particles and approx twice the potency of Clenil
Why are oral corticosteroids used for in asthma and COPD?
Usually a short term rescue therapy to bring symptoms under control e.g.
-asthma exacerbation
-COPD when patient gets URTI, usually with antibiotics
What are local adverse affects of corticosteroids?
Hoarseness
Throat irritation
Dysphonia- changes in voice
Candida- T cells important against fungal infections
What are practical considerations in corticosteroids?
Can be given in multiple routes but lead to more systemic SE
Effect can be slow so needs to make sure to take regularly
Don’t stop them abruptly
Children can take it, can leads to slow growth
COPD, only in combo with LABA or LAMA
Give the counselling points for corticosteroids:
Regular use as preventative
Morning and evening dose, usually fits in with routine
Oral dose first thing in morning with breakfast as decreases GI disturbances and better with natural steroid production
Which corticosteroid are less likely to contribute to adrenal suppression and why?
Fluticasone, Mometasone and Ciclesonide
Poorly absorbed from the GI tract and undergo almost complete pre-systemic metabolism
Which steroids are used at which point in the treatment of airway diseases?
Regular bronchodilator: low dose inhaled beclometasone
More severe: high dose inhaled fluticasone
Acute exacerbations: IV hydrocortisone and oral prednisolone
What are bronchi and trachea usually lined with and made up of?
Ciliated columnar epithelium
Have cartilage to prevent collapse, then goes to half rings and then to smooth muscle
What is the zone in the bronchi regions and then after this?
In the bronchi regions- air conducting
After bronchi regions- gas exchange zone
What are the types of cells lining the bronchial region and what do these do?
Ciliated cuboidal cells
Secrete no mucous and serous glands
What are alveoli lined with and what do they not contain?
Lined with phospholipids
Don’t have smooth muscle/ cartilage
Which type of enzymes are found in the bronchi and alveoli region?
Drug metabolising enzymes:
- Cyp450
- Esterase
- Protease
- Peptidases
What type of drug can be deposited in the lung and how much is?
5% and polar macromolecule drugs
Less than 5micrometers
How much drug is swallowed rather than effectively used and why?
95%, trapped in cilia and wafted back up, mucociliary clearance
Abosrption from gut and liver metabolism
What size particles are rapidly and slowly absorbed?
Macromolecular, less or equal to 40kDa rapidly absorbed
Molecules higher or equal to 40kDa absorbed more slowly
What type of drug does the lung prefer?
Lipophilic over hydrophilic
Where are the receptors of histamine blockers?
Vascular endothelial cells, smooth muscle of bronchi
Where are the receptors of beta agonists found?
B2 receptors in trachea, bronchial smooth muscle, serous glands
Where are the receptors for anticholinergics found?
Tracheal, bronchial smooth muscle, serous glands
Where are the receptors for corticosteroids found?
Epithelial cells, fibroblasts, basophils, macrophages and lymphocytes
Conncective tissues at all levels of respiratory tree
How long should you wait between doses of inhalers?
30 seconds
Which system do muscarinic receptors work on?
Parasympathetic, apart form sympathetic for sweat glands
What happens in a parasympathetic reaction?
Decrease HR, dilation of BV, constriction of bronchi, increased GIT motility, bladder contraction, pupil contraction, gland secretion
What are muscarinic receptors?
GPCRs
Activated by acetylcholine
Classic 7 transmembrane domain
Muscarine, an alkaloid from the fungus an an agonist for these receptors
Name the types of muscarinic receptors and where are they found:
M1- neural, CNS
M2- cardiac, heart
M3- glandular, increasing secretion / smooth muscle
M4 and M5, mainly CNS, not well defined
Which muscarinic receptors signal via calcium?
M1, M3, M5- the odd numbers, Gq G protein