Asthma 01.15 Flashcards
Two year old with 1st episode wheeze at 6 months
• 5 further episodes associated with URTIs
• No other chest symptoms
Fever <38.5
•Weight gain good
Broncholitis - commonest acute LRTI in infancy.
In 2 year old:
Respiratory distress- tachypnoea
- grunting
- subcostal & intercostal recession
- tracheal tug
- nasal flaring
• Hyperinflation with palpable liver edge
• Widespread fine crepitations throughout respiratory cycle
• Often prolonged expiratory phase with wheeze
• Hypoxia
• Fever in most (
Broncholitis - commonest acute LRTI in infancy.
3 year old with:
Exercise – wheeze, cough, SOB, tight chest
• Nocturnal cough
• ‘tummy ache’
• Wheeze with URTIs
• Nasal symptoms
• Atopy – eczema, hayfever, food allergies
Asthma - atopic
Signs you would expect in child with chronic asthma untreated:
- Fingers?
- Growth chart?
- Skin?
- Chest & ribs?
- Face?
Fingers - Clubbing Grow chart - Failure to thrive Chest - Harrison sulci, barrel chest Skin - Ezcema Face - Allergy – shiners (from constantly rubbing eyes), nasal crease (constantly wiping / rubbing nose), salute sign
Which type of CD4+ T helper cell is pro-atopic and pro-asthmatic? Th1 or Th2
Th2
Once an allergen has been presented to Th2 cell by dendritic cell, Th2 cell stimulates activity of what 3 cell types, causing inflamm. response?
- Eosinophils
- Mast cells
- B cells - IgE
4 key symptoms of asthma
- wheeze
- SOB
- chest tightness
- cough
What would you expect on a peak flow chart over a week?
Diurnal variation - lowest reading in morning “morning dippers”
Mast cell production of histamine, prostoglandins and leukotrienes occurs within minutes and causes what physiological response & what symptom of asthma (2)
Bronchoconstriction
Wheeze
Cytokines IL 4 and IL 13 are produced within hours by mast cells, causing what cellular and what physiological probs (2)
Eosinophil recruitment
Mucous production
What stage of asthma severity is this (1-4):
80% expected,
<2 nocturnal epis. / month
Stage 1 - Intermittant
What stage of asthma severity is this (1-4):
>1/wk, but less than 1/day
FEV1 / PEF >80% expected, variability 20%-30%
Nocturnal symp >2/mo
Stage 2 - Mild persistant
What stage of asthma severity is this (1-4):
Daily attacks, affect activity
FEV1 / PEF 60-80% expected,
Nocturnal symp >1/week
Stage 3 - Moderate persistent
What stage of asthma severity is this (1-4):
Continuous attacks, limit phys activity
FEV1 / PEF <60% expected,
Nocturnal symp frequent
Stage 4 - Severe persistent asthma
This asthma treatment is a SABA (short acting beta agonist)
Increases cAMP production - relaxation of sm muscle
Salbutamolin (ventolin) / terbutaline also
Other than bronchodilation what are 2 other effects of salbutamol
Incr mucus clearance
Inhib inflamm cytokines
S/E salbutamol (3)
Tremor
Tachycardia
Hypokalaemia
Give 1 example of each of the following asthma medications:
- SABA
- Corticosteroid
- LABA
- Leukotriene receptor agonist
- Xanthines
- SABA - Salbutamol
- Corticosteroid - Beclometasone
- LABA - Salmeterol
- Leukotriene - Montelukast
- Xanthine - Theophylline
Therapeutic effects of corticosteroids for asthma (3)
- Reduce immune cell numbers (eosin. T lymph etc)
- Red. inflammatory mediators
- Red. vascular permeability
S/E corticosteroids in LONG term use (4)
Osteoporosis
Incr infection risk
Hyperglycaemia
Growth retard. in kids
S/E corticosteroids in SHORT term use (2)
Candida oral infection
Sore throat
Fluticasone and budesonide are what type of asthma drug
corticosteroids
What must ALWAYS be used in combination with a steroid for asthma treatment
LABAs e.g salmeterol
Symbicort (Red/white), Seretide (purple) and Fostair (brown) are examples of what type of inh.
Combination steroid and LABA - preventer and reliever
3 therapeutic effects of Leukotriene receptor antagonists
- Red wheeze & bronchoconstriction
- Reduce eosin. and basophil
- Red. mucus & microvasc leakage
S/E of montelukast etc (2)
GI disturb
Headache
Xanthines - therap. effect?
Red inflamm mediators
SE Xanthines (very narrow therap window) (4)
- Naus & vom
- Tachycardia
- Convulsions
- Coma!
Maj. interaction of Xanthines
Macrolides e.g clarithromycin - incr. blood levels of theophyliine
What is Omalizumab and how does it help with asthma
Monocl antibody - bind to IgE prevent interact with mast cells.
4 maj risks of steroid use in children
- Cushings
- Adrenal suppression
- Fungal in mouth
- Reduc. resist to chickenpox (h.zoster)
This drug can be nebulised for severe acute asthma attacks
Ipratropium (anti-muscarinic)
This dryg can be given IV for severe acute asthma attacks
IV magnesium sulphate
Phosphodiesterase inhibits cAMP and therefore inhibits relaxation of sm muscle.
Which drug inhibits phosphodiesterase, thus helping sm musc relaxation?
Xanthines eg Theophylline
What is FEV1
Forced Epired Vol in 1 sec - amount breathed out in 1 second from FULL INSPIRATION
What is FVC
Forced Vital Capacity - Amount of air expired in WHOLE BREATH from FULL INSPIRATION
What is PEFR
Peak Expiratory Flow Rate (L/s) = percentage figure of expected rate in a healthy individual. e.g. Mild asthma - expect PEFR >80%
In Severe it can be <60%
Below what age are lung function tests less reliable
5years
Name 2 obstructive disorders and 2 restrictive disorders
Obstructive: Asthma, Cystic Fibrosis, COPD
Restrictive: Severe kyphosis, pleurisy, diaphragmatic hemiparalysis
4 clinical features used to distinguish COPD from Asthma
- COPD - chronic cough
- Asthma - reversibility with inhalers
- Smoking history - COPD
- Nocturnal variation - asthma
DD for Chronic cough +/- wheeze in under 1yo (5)
- Bronchiolitis
- Pertussis (hooping cough) / other infection
- GORD
- Transient early wheeze
- Cf
others. ..
This virus is:
The commonest acute lower respiratory tract infection in
infancy.
• Respiratory Syncytial Virus (RSV) in 80% cases, others
adenovirus, influenza and parainfluenza virus.
• Winter months.
• Necrosis of the ciliated cells and proliferation of non-ciliated
cells.
• Bronchiolar obstruction, atelectasis and hyperinflation
• Leads to hypoxia, hypercarbia and ventilation
Broncheolitis
DD for chronic cough +/- wheeze in pre-school kids <5yo (7)
1. Transient early wheeze 2, Asthma 3. Infections – Recurrent Viral URTIs – Bacterial (pertussis or persistent collapse – TB 4. Inhaled foreign body 5. Passive smoking 6. Cystic fibrosis + bronchiectasis 7. GORD others...
7 yr old Wheezy since 3 yrs with URTIs • Infantile eczema • Allergy reaction to egg at 14 months • Wheezy when visits grandma who has a cat • Treatment – bronchodilator prn • Recently waking with cough at night • Most likely diagnosis?
Asthma
Recurrent viral URTIs
others…
