Week 210 - Asthma Flashcards
What is the definition of Asthma?
Chronic Inflammatory Disorder characterised by airway Hyper-responsiveness that is REVERSIBLE either spontaneously or with treatment
What are the FOUR most common symptoms of Asthma?
Wheeze
Breathlessness
Cough
Chest Tightness
What sort of diurnal variation does Asthma exhibit?
Peak flow lowest early morning
What pattern do you expect to find on spirometry?
FEV/FVC 12% FEV1 post-bronchodilator
What are the two types of Asthma?
Extrinsic - IgE mediated (Atopic, Occupational)
Intrinsic - non-immune (infection, cold, exercise, stress)
What occupational sensitisers exist?
Isocyanates - industrial workers Flour - Bakers/pastry makers Colophony/Fluxes - Electronic workers Latex - Lab/Hospital Aldehydes - Chemical/Wood workers Enzymes - Detergent manufacturers Animals Wood dusts - timber workers
What type hypersensitivity is Asthma?
Type 1 hypersensitivity (IgE mediated)
What are the four papillae of the tongue?
Vallate - biggest
Filiform - no taste buds (only one)
Fungiform
Foliate
What nerves innervate the posterior 1/3 of the tongue?
IX (glossopharyngeal)
What nerves innervate the posterior 2/3 of the tongue?
V3 and Corda Tympani (VII)
What is the innervation of the Intrinsic and Extrinsic muscles of the tongue?
Intrinsic and Extrinsic = Hypoglossal nerve (XII) Exception Palatoglossus (ext.) - vagus (X)
What does the Otic Ganglion Supply (directly under foramen ovale)?
Innervates the Parotid gland
via Auriculotemporal Nerve
What direction with the Tongue deviate in a UMN lesion?
Opposite side to lesion
What are the three major pairs of salivary glands?
Parotid (Stenson’s Duct)
Submandibular (Wharton’s Duct)
Sublingual (ducts of Rivinus)
Where does the Stenson’s Duct empty and what gland does it arise from?
From parotid
to Papilla opposite upper 2nd molar tooth
What is Frey’s Syndrome?
Post surgery to the parotid gland
Damage to auricotemporal nerve
Leads to gustatory sweating
Give two examples of BENIGN parotid neoplasms
Pleomorphic Adenoma
Warthin’s Tumour
Give two examples of MALIGNANT parotid neoplasms
Adenoid Cystic Carcinoma
Adenocarcinoma
Squamous cell carcinoma
Look for Facial Nerve Palsy
What do Eosinophils secrete?
Leukotrienes - smooth muscle contraction
ECP
MBP - epithelial damage, loss of tight junctions,stimulates Cl and water secretion
Eosinophil peroxidase
What do Mast cells secrete?
Histamine - bronchoconstriction, mucus secretion Serotonin Serine proteases (LT-C4) - bronchoconstriction
What effect do IL-4 and Il-13 have on B cells?
Ig subclass switching (to class E) in B cells
What is the “Late Phase Response” in Asthma?
Pt may respond to treatment initially but later the symptoms reoccur
Bronchodilators do not fully reverse the airway obstruction
What effect does Sodium Cromoglycate have?
Mast Cell Stabiliser
What is the mechanism of action of Mepoluzimab?
mAb towards IL-5
How can Aspirin induced Asthma arise?
NSAIDs/Aspirin inhibit COX-2 -> can aggravate asthma
What is the commonest cause of Bronchiolitis?
RSV (in 80% of cases)
What is the mechanism of action of Salbutamol?
↑cAMP –> PKA
Relaxes bronchial smooth muscle
What side-effects of Salbutamol?
Tremor
Tachycardia
Hypokalaemia
What corticosteroids are available for the treatment of asthma and what colours do they come in?
Beclometasone (Brown)
Fluticasone (Red) - much more potent
Budesonide (Brown)
Name some LABAs, and how are they different to SABAs
Salmeterol(slow onset of action), Formoterol (quicker acting)
Prolonged action by lipid side chain (at least 12 hrs)
Does not compromise SABA action
What is in Seretide?
Fluticasone + Salmeterol (cortico +LABA)
What is in Symbicort?
Budesonide & Formoterol (cortico + quick LABA)
Can be used for prevention & relief
What is in Fostair?
Beclometasone & Formoterol (cortico + quick LABA)
Name some Leukotriene antagonists
Montelukast, Zafirlukast
Reduce Wheeze and Bronchoconstriction
Reduce Eosinophil & basophil influx
Name some side-effects of Leukotriene antagonists
GI disturbances, Headache
Name some Xanthines and their mechanism of action
Theophylline, Aminophylline Inhibit phosphodiesterase (breaks down cAMP into AMP)
What are the problems and side-effects of using Xanthines?
Narrow therapeutic range
Prescribe by brand
Drug interactions important
S/E - Nausea, Vomiting, Tachycardia, Convulsions, Coma
How does IV magnesium sulphate work?
↓[Ca] in blood
What are the risks associated with Omalizumab
IgE mAb
↑risk of infection with any mAb
Name possible causes of an Acute ↑PaCO2
Severe acute asthma
Severe pneumonia
Exacerbations of COPD
Name some chronic causes of ↑PaCO2
COPD, Respiratory muscle weakness (neuromuscular disorders, thoracic skeletal deformities)
Leads to renal retention of HCO3 and normalisation of pH
What is compensated Respiratory acidosis?
↑PaCO2, ↓PaO2, Normal pH
In this case PaO2 drives respiration
Giving O2 leads to hypoventilation
Name some causes of Respiratory Alkalosis
Hyperventilation ( Asthma, Pleurisy, PE)
What is compensated Respiratory alkalosis?
HCO3 is excreted by kidneys -> normalisation of pH
What can cause Metabolic Acidosis?
↓HCO3, ↓pH
Acute Renal Failure
Diabetic Ketoacidosis
Lactic Acidosis
What can cause Metabolic Alkalosis?
↑HCO3, ↑pH
Often related to tubular K+ depletion
