Management of COPD & Asthma Melissa Brittle & Jessica Macaro.
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Transcript of Management of COPD & Asthma Melissa Brittle & Jessica Macaro.
Management of COPD & AsthmaMelissa Brittle & Jessica Macaro
Overview
Drugs used in airway disease
Bronchodilators
A. β2 Agonists
B. Anti-cholinergics
C. Methylxanthines
D. Leukotriene antagonists
Anti-inflammatory agents
A. Glucocorticoids
B. Mast cell stabilisers
Monoclonal Antibodies
Asthma
Acute management
Long term management
COPD management
Bronchodilators
β2 Agonists
1. β2 agonist binds to GPCR
2. This leads to activation of Adenyl cyclase
3. Adenyl cyclase converts ATP to cAMP which activates Protein Kinase A (PKA)
4. PKA phosphorylates myosin light chain kinase (MLCK), inactivating it, and therefore reducing smooth muscle contraction in the airway.
Short acting (SABA) = salbutamol, TerbutalineLong acting (LABA) = salmeterol, Formoterol.
Side effects- Tremor- Tachycardia- Headache- Cardiac arrhythmia - Peripheral vasodilation- Hypokalaemia
Can you name any?
1
2
3
4
Anti-cholinergics1. Blockade of Muscarinic M3 receptors.
2. Reduces action of Phospholipase C (PLC) leading to
a) A reduction in calcium release from endoplasmic reticulum (ER)
b) A reduction in calcium uptake into the cell
Normally, calcium binds to Calmodulin which activates MLCK, which in turn activates myosin leading to smooth muscle contraction.
3. Without Calcium, smooth muscle contraction (i.e. bronchoconstriction) is inhibited.
Short acting (SAMA) = IpratropiumLong acting (LAMA) = Tiotropium
Side effects everything dries up!!- Dry mouth Nausea- Constipation Urinary retention- Cough Glaucoma - Headache
Can you name any?
12
a
b
3
Methylxanthines
1. Methylxanthines inhibit phosphodiesterase (PDE) which normally breaks down cAMP into 5’AMP
2. This allows cAMP levels to rise thus promoting muscle relaxation
AminophyllineTheophylline
Small therapeutic window- take care with dose Multiple drug interactions Side effects…- Insomnia- Nausea and vomiting- Cardiac arrhythmias - Seizures
Can you name any?
What breaks cAMP down?
Leukotriene Antagonists
Leukotrienes cause airway inflammation and bronchospasm
1. Leukotriene antagonists block cysteinyl leukotriene (Cys LT) receptors.
2. This leads to reduced inflammatory response and reduced exercise induced symptoms in asthma
MontelukastZafirlukast
Side effects…- Abdominal pain- Headache- Thirst- Restlessness
Can you name any?
Anti-inflammatory agents
Glucocorticoids1. Glucocorticoids cause
a) Expression of anti-inflammatory products
b) Inhibition of pro-inflammatory products e.g. cytokines, vasodilators, leukotrienes etc
2. This results in reduced oedema and mucous production which contributes to narrowed airways in asthma and COPD.
Inhaled- beclomethasone, fluticasoneOral- PrednisoloneIV- hydrocortisone
Side effects…- Cushings
syndrome- Oral steroids
have more effects than inhaled.
Can you name any?
Mast cell stabilisers
Act by stabilising mast cell membranes therefore preventing histamine release
Unfortunately not very effective but have few side effects
Typically used in children with asthma
Useless in COPD or acute asthma because histamines have already been released.
Sodium cromoglycate, nedocromil.
Side effects…- Bitter taste- Paradoxical
bronchospasm
Can you name any? We can’t…
What do mast cells release?
MONOCLONAL ANTIBODIES
• Anti-IgE antibodies form complexes with free IgE
• Useful to prevent allergic asthma
• Very expensive and not often prescribed
Omalizumab
Mast cell
Can you name any?
ACUTE MANAGEMENT OF ASTHMA
OSHIT…
O – Oxygen S – Salbutamol H – Hydrocortisone (IV) (if in hospital) or Prednisolone (oral) (if in GP)I – Ipratropium T – Theophylline
Reliever
Inhaled SABA e.g salbutamol
Preventer
Add inhaled steroid e.g. fluticasone
Controller
Add inhaled LABA e.g. salmeterol
Higher dose inhaled steroid+Leukotriene antagonist, theophylline or β agonist
Oral steroid e.g. prednisolone
LONG TERM MANAGEMENT OF ASTHMA
Step by step approach
Reliever
Inhaled SABA e.g salbutamol
Preventer
Add inhaled steroid e.g. fluticasone
Controller
Add inhaled LABA e.g. salmeterol
Higher dose inhaled steroid+Leukotriene antagonist, theophylline or β agonist
Oral steroid e.g. prednisolone
MANAGEMENT OF COPD
• Smoking cessation advice• Oxygen• Bronchodilator therapy
o SABA e.g. salbutamolo SAMA e.g. ipratropium
• Combination therapyo LABA e.g. salmeterolo LAMA e.g. tiotropiumo Inhaled steroid e.g. fluticasone
• Oral methylxanthines e.g. theophylline