Pharmacology Flashcards
Where are cell bodies of the parasyympathetic preganglionic fibres located
Brainstem
Where are cell bodies of parasympathetic postganglionic fibres located
Bronchi and bronchiole walls
Stimulation of postganglionic cholinergenic fibres causes
Bronchial smooth muscle contraction (mediated by M3 ACH on ASM)
Increased mucus secretion (mediated by M3 ACH on goblet gland cells)
Stimulation of postganglionic noncholingergenic fibres causes
Bronchial smooth muscle relaxation (mediated by NO and VIP)
In the sympathetic division there is no innervation of
bronchial smooth muscle
Parasympathetic postganglionic fibres supply
Submucosal glands and smooth muscle of blood vessels
Stimulation of parasympathetic postganglionic fibres causes
Bronchial smooth muscle relaxation via B2- adrenoreceptors on ASM
Decreased mucus secretion mediated by B2-adrenoreceptors on goblet cells
Increased mucociliary clearance mediated by B2-adrenoreceptors on epithelial cells
Vascular smooth muscle contraction mediated by A1-adrenoreceptors on vascular smooth muscle cells
Contraction of smooth muscle caused by
Myosin light chain kinase phosphorylated
Relaxation of smooth muscle caused by
Dephosphorylation of Myosin phosphate
What causes the rate of phosphorylation to exceed rate of dephosphorylation
Presence of Ca2+
Relaxation requires Ca2+ to return to normal level
How does Ca2+ return to normal level
Active transport
Asthma
Recurrent, reversible obstruction of airways
Causes of asthma
Allergens
Exercise
Resp infection
Smoke, dust, environmental pollutants
Asthma patients present with
Tight chest
Wheeze
Cough
Difficulty breathing
Chronic asthma
Pathological changes that result from long standing inflammation:
- Increase mass of smooth muscle
- Accumulation of interstitial fluid
- Increased secretion of mucous
- Epithelial damage (exposing sensory nerve endings)
- Sub-epithelial fibrosis
Asthma caused FEV1 to
decrease
mild asthma displays
hypersensitivity
severe asthma displays
hypersensitivity
hyper-reactivity
FEV1
Forced expiratory volume in 1 second
In atopic individuals, stages of asthma immunity
- allergen
- phagocytosis
- Strong Th2 response, IgE
Development of allergic asthma
- Allergen in airway epithelium
- CD4+ express Th0 cells
- Th0 cells becomes Th2
- Th2 activates B cells
- B cells become IgE
- Th2 also release IL4 and IL13 causing mast cells to express IgE
- Stimulates Ca2+ entry, leukotriene release, contraction of smooth muscle
Stages in late phase of asthma
- Epithelial damage
- Airway hyper-responsiveness
- Bronchospasm, wheezing, cough, mucous over secretion
- Airway inflammation
2 categories of drugs used in treatment of asthma
Relievers (bronchodilators)
Controllers (Anti-inflammatory)
Relievers
SABA’s
LABA’s
CysLT1 receptors agonist
Controllers
Glucocorticoids
Cromoglicate
Humanised IgE monoclonal antibodies
B2 - adrenoreceptors agoinsts
antagonist of all spasmogens
Bronchodilators
SABA’s
Short Acting B2-adrenoreceptor Agonist
Salbutamol
Increase mucous clearance and decrease mediator release from mast cells and monocytes
LABA’s
Long Acting B2-adrenoreceptor Agonist
Salmeterol
Formaterol
Should not be used as monotherapy, should be used with gluticosteroids
used in nocturnal asthma
LABA
CysLT1
Cysteinyl Leukotriene Receptor Antagonists
Act competitively at CysLT1 receptor stopping smooth muscle contraction
Montelukast
Methylxanthines
Inhibits PDE3
Combine bronchodilator and anti-inflammatory actions
Second line drugs used with B2-adrenoreceptor agonists and glucocorticoids
Corticosteroids
Glucocorticoids Anti-inflammatory Reduces immunological response Prevent inflammation Resolve established inflammation
Cromones
Mast cell stabilisers
Weak anti-inflammatory response
Sodium cromoglicate
Reduce phases of asthma attack
More effective in young children
Monoclonal antibodies against IgE
Binds to IgE to prevent it binding to cells
Asthma Treatment
- SABA (salbutamol)
- Inhaled corticosteroid (beclomethasone)
- LABA + ICS (salmeterol)
- Increase glucocorticoid dose, add 4th drug
- Oral glucocorticoid (prednisolone)
Synthetic glucocorticoid used to prevent inflammation in chronic asthma
Inhaled beclometasone
Synthetic glucocorticoid used in severe or rapidly deteriorating asthma
Oral prednisolone
Weak anti-inflammatory used in allergic asthma
Inhaled Sodium Cromoglycate
volume of air breathed in and out per minute
pulmonary ventilation
volume of air exchanged between atmosphere and alveoli per minute
Alveolar ventilation
Major inspiratory muscle in a sheet, containing crura
Diaphragm
Palpable reference point used in BEC
Xiphoid process
Site of oblique fissure anteriorly
Rib 6
Most O2 is transported
bound to haemoglobin
Most Co2 is transported
as bicarbonate
A small proportion of O2 is transported
in solution
Carries deoxygenated blood, drains into superior vena cava and arches around right lung root
Azygous vein
Arise from anterior surface of descending aorta
Bronchial arteries
Surrounded by vessels and may appear black on dissection
Pulmonary lymph nodes
Palpable with jugular notch
Trachea
Level where lower respiratory tract begins
C6 vertebrae
Anatomical landmark for cardiopulmonary resuscitation
Xiphoid process
Site of horizontal fissure
Right 4th rib
Level of carina
Rib 2
Level of oblique fissure posteriorly
T3 vertebrae
Factor that most increases pulmonary ventilation
tidal volume
Methylxanthine used as add-on therapy in asthma. Serum levels must be monitored due to drug interaction
Oral theophyline
Anti-inflammatory that can trigger bronchospasm in sensitive individuals
Oral ibruprofen
A CysLT-1 receptor antagonist, used as an add-on therapy in asthma
Oral montelukast
Monoclonal antibody against IgE that reduces IgE receptor expression
Subcutaneous omalizumab
SABA used to relieve bronchospasm in mild to moderate asthma
inhaled salbutamol
Add on B-2 agonist that responds poorly to initial management
Inhaled salmeterol
B2 agonists end in
ol
B2 agonist examples
Salbutamol
Salmeratol
Inhaled corticosteroids
Beclomethasone
Fluticasone
Inhaled corticosteroids end in
One
CysLT-1 examples
Montelukast
Zafirlukast
CysLT-1 end in
lukast
Methylxanthines
Theophyline
Asthma immune response
- IgE antibody attaches to mast cells
- Degranulation occurs
- Inflammatory mediators released causing bronchospasm, mucosal oedema and mucous formation
Pathophysiology of COPD
Inhalation of noxious gases/particles leads to inflammation, mucocilliary dysfunction and tissue damage
Cigarette smoking with COPD
- Activates macrophages
- Activates neutrophils
- Proteases released causing alveolar wall dysfunction (emphysema) and mucous hypersecretion (bronchiectasis)
COPD Treatment
- SABA
- LAMA
- LABA
- LAMA/LABA combination inhaler
- LABA/ICS combination inhaler
- LABA/LAMA/ICS combination inhaler
LAMA
Long acting muscarinic receptor agonists
Reduce bronchospasm caused by irritant
Decrease mucous secretion
Treat acute exacerbation of asthma
Oxygen Salbutamol Hydrocortisone Ipratropium Theophylline Magnesium sulfate ANaethetist
Treat acute exacerbation of COPD
ipratropium Salbutamol Oxygen Amoxicillin Prednisolone
Aetiology of restrictive thoracic disease
Impaired alveolar gas exchange
Fluid in alveolar spaces
Consolidation of alveolar air spaces
Inflammatory infiltrate of alveolar walls
LAMA example
Ipratropium
PDE4 inhibitors
COPD only
Roflumilast
Anti-inflammatory
Mucolytics
COPD only
Oral carbocisteine
Reduce sputum
D dimers
Fibrin degradation product
Increased = thrombosis, inflammation, malignancy, heart failure
COPD
Airflow reduction, partially reversible, progressively worsens
2 types of COPD
Chronic Bronchitis
Emphysema
Chronic Bronchitis
Inflammation of bronchi and bronchioles
Cough
Clear sputum
Increasing breathlessness
Emphysema
Distension and damage to alveoli
Destruction of acinal pouching in alveolar sacs
Loss of elastic recoik
LAMA’s end in
ium
Fexofenadine
Competitive H1 receptor antagonist used to treat allergic rhinitis
Ipratropium
A short acting drug that blocks acetylcholine non-selectively,
Rofumilast
PED4 inhibitor, given orally for COPD
Sodium cromoglicate
Mast cell stabiliser used in asthma
Rhinitis
Inflammation of nasal mucosa
May be allergic, non-allergic or mixed
Allergic Rhinitis
Seasonal
Perennial
Episodic
Non-allergic Rhinitis
Doesn't involve IgE Infection Hormonal Imbalance Vasomotor disturbances Medications
Anti-inflammatory treatment
Glucocorticoids
Mediator receptor blockade treatment
H1 receptor antagonist
CysLT receptor antagonist
Nasal blood flow treatment
Vasconstrictors
Anti-allergic
Sodium cromoglicate