3- Paediatric Respiratory Flashcards
Cough classification
Acute
- Infective e.g. viral, bacterial
- Non-infective e.g. foreign body, irritant toxin
Subacute (3-8 weeks)
- Post viral cough
- Pertussis and similar infections
- Children recovering from pneumonia
Chronic
- >8 weeks
causes of acute onset cough
1) Respiratory infection
Upper:
- rhinovirus
- coronavirus
- croup
- epiglottis
- pharyngitis
Lower
- pneumonia
- bronchitis
- bronchiolitis
2) Foreign body
history for chronic cough
1) How and when did it start?
2) Nature of cough: wet/ dry/whooping
3) Diurnal variation, triggers of cough, habit stop when sleep
4) Fx
- Atopy
- Smoking
- Contact with TB
5) Associated features
- Wheezing
- Failure to thrive
- Progressive worsening
- Neuromuscular weakness
- Reflux
- Aspiration
causes of chronic cough
- Persistent bacterial bronchitis (PBB)
- Recurrent aspiration
- Bronchiectasis
o Progression of PBB
o Recurrent aspiration
o CF
PCD
immune problems - Rhinitis
- Immune problems
- GORD
investigations for chronic cough
Investigations
- History – history of infection (acute/recurrent), nasal symptoms, failure to thrive, wheeze, response to previous treatments, atopy etc.
- CXR
- Bloods – immune screen (T-cell subsets, antibody response, immunoglobulins), allergy markers (Eosinophils, IgE, sIgE)
- Lung function test if old enough
- swallow assessment- aspiration
2nd line investigations
- Sweat test
- Bronchoscopy
- pH/impedance study
- High Resolution CT
- Nasal brushings- primary ciliary dyskinesia testing
Protracted bacterial bronchitis Background
Persistent bacterial infection in lower airways
- Presence of wet cough (>4 weeks’ duration)
- Absence of symptoms or signs (i.e. specific cough pointers) suggestive of other causes
- Cough resolves following a 2–4-week course of an appropriate oral antibiotic i.e. co-amoxiclav
presentation of PBB
investigations for PBB
Investigations
- History – history of infection (acute/recurrent), nasal symptoms, failure to thrive, wheeze, response to previous treatments, atopy etc.
- CXR
- Bloods – immune screen (T-cell subsets, antibody response, immunoglobulins), allergy markers (Eosinophils, IgE, sIgE)
- Lung function test if old enough
2nd line
- Sweat test
- Bronchoscopy
- pH/impedance study
- High Resolution CT
- Nasal brushings
investigations for PBB
Investigations
- History – history of infection (acute/recurrent), nasal symptoms, failure to thrive, wheeze, response to previous treatments, atopy etc.
- CXR
- Bloods – immune screen (T-cell subsets, antibody response, immunoglobulins), allergy markers (Eosinophils, IgE, sIgE)
- Lung function test if old enough
2nd line
- Sweat test
- Bronchoscopy
- pH/impedance study
- High Resolution CT
- Nasal brushings
investigations for PBB
Investigations
- History – history of infection (acute/recurrent), nasal symptoms, failure to thrive, wheeze, response to previous treatments, atopy etc.
- CXR
- Bloods – immune screen (T-cell subsets, antibody response, immunoglobulins), allergy markers (Eosinophils, IgE, sIgE)
- Lung function test if old enough
2nd line
- Sweat test
- Bronchoscopy
- pH/impedance study
- High Resolution CT
- Nasal brushings
management of PBB
- sputum culture -> antibiotic therapy
Children who present with wheezing are diagnosed differently depending on their ….
Age
Bronchiolitis <1
- Prodromal
- RSV
Viral wheeze <5
- Prodromal
- Occurs at time of virus
Asthma exacerbation >5
- Doesn’t have to have prodrome
- Can be triggered by infection but also hay fever, cold, exercise
general management of wheeze
for bronchiolitis
- supportive care (not salbutamol)
for viral induced wheeze and asthma:
- salbutamol
- steroids
Prognosis of wheeze
- Bronchiolitis- self limiting
- Viral wheeze – you grow out of
- Asthma – still there after age of 5
Viral Induced Wheeze or Asthma?
The distinction between a viral-induced wheeze and asthma is not definitive. Generally, typical features of viral-induced wheeze (as opposed to asthma) are:
- Presenting before 3 years of age
- No atopic history
- Only occurs during viral infections
Asthma can also be triggered by viral or bacterial infections, however it also has other triggers, such as exercise, cold weather, dust and strong emotions. Asthma is historically a clinical diagnosis, and the diagnosis is based on the presence of typical signs and symptoms along with variable and reversible airflow obstruction.
Viral induced wheeze background
- Describe an acute wheezy illness caused by viral infections
- Typically under 3- due to small airways
Pathophysiology of viral induced wheeze
- When airways encounter virus (RSV or rhino) they develop a small amount of inflammation and oedema -> this restricts the space for air to flow
- Inflammation also triggers smooth muscles of the airway to constrict
Presentation of viral induces
Evidence of a viral illness (fever, cough and coryzal symptoms) for 1-2 days preceding the onset of:
* Shortness of breath
* Signs of respiratory distress
* Expiratory wheeze throughout the chest
management of viral induced wheeze
Same as acutee asthma in children
- Salbutamol
- Oxygen as needed
- Ipratrium if needed
asthma background
- Commonest respiratory condition
- Chronic inflammatory airway disease leading to variable airway obstruction
- Atopic condition
o Asthma
o Eczema
o Hay fever
o Food allergies
Pathophysiology of asthma
- Smooth muscle in airway is hypersensitive and responds to stimuli by constriction and causing airflow obstruction
- Bronchoconstriction is reversible with bronchodilators such as inhaled salbutamol
- Typical triggers
o Dust
o Animal
o Scold air
o Exercise
o Smoke
o Food allergens
o Stress
Risk factors for asthma
- Personal/familial history of atopy
- Inner city environment
- Obesity
- Viral infections in early childhood
- Smoking
If asthma diagnostic doubt e.g. if low probability of asthma and the child his symptomatic
Send to a specialist
Spirometry with reversibility testing (in children aged over 5 years)
- <70% (may be diff in children)
- 12% reversibility = diagnostic of asthma
Direct bronchial challenge test with histamine or methacholine (non-selective muscarinic receptor agonist in PNS) (metacholinergic challenge test)
- Used to help diagnose asthma
- Degree of narrowing measured by spirometer
Fractional exhaled nitric oxide (FeNO)
- Inflammation of the lungs
Peak flow variability
o Measured by keeping a diary of peak flow measurements several times a day for 2 to 4 weeks
spirometry definitions
- FVC = The volume breathed out during the forced expiration.
- FEV1 = The volume breathed out during the first second
- FEV1/FVC = The proportion of the FVC that is breathed out in the first second
- PEFR = The Peak Expiratory Flow Rate – the gradient of the graph at time 0, which corresponds to the highest rate of flow of air from the lungs.
asthma management: stewpise approach
Step 1 (mild, intermittent asthma)
- Salbutamol (Beta 2-agonist)
- Everyone offered and should be used PRN
Step 2 (if use of salbutamol more than 3 times a week, symptoms more than 3 times a week, waking due to asthma more than once a week)
- Inhaled corticosteroid
Step 3 (if Beta-2 agonist/ inhaled steroid not enough)
Add on:
- Leukotriene receptor antagonist (LTRA- Montelukast) before treatment with a long acting beta 2 agonist (LABA) e.g. salmeterol
- LABA should never be used without concurrent use of inhaled steroid
Step 4 (persistent poor control)
- Add beclomethasone
- And/or theophylline or beta2-agonsit tablet
Step 5
- Continuous or frequent use of oral steroids, maintaining high dose inhaled steroids
- (Referral to resp doctor at step 4-5)
- Omalizumab- option for treating severe persistent allergic IgE mediated asthma
Inhaler technique
Better technique improves asthma management. Poor technique results in medication in mouth and throat- oral thrush (steroids). Ideally used with a spacer to maximise effectiveness- almost always spacers in paeds (facemask up to 4/5, then mouth piece)
presentation and classification for acute asthma exacerbation
Presentation
- Progressively worsening shortness of breath
- Signs of respiratory distress
- Fast respiratory rate (tachypnoea)
- Expiratory wheeze on auscultation heard throughout the chest
- The chest can sound “tight” on auscultation, with reduced air entry
- A silent chest is an ominous sign. This is where the airways are so tight it is not possible for the child to move enough air through the airways to create a wheeze. This might be associated with reduce respiratory effort due to fatigue.
o A less experienced practitioner may think because there is no respiratory distress and no wheeze the child is not as unwell, however in reality this a silent chest is life threatening.
ABGs not very commonly used in acute management
pathophysiology of bronchiolitis
- When a virus affects the airways of adults, the swelling and mucus are proportionally so small that it has little noticeable effect on breathing.
- The airways of infants are very small to begin with, and when there is even the smallest amount of inflammation and mucus in the airway it has a significant effect on the infants ability to circulate air to the alveoli and back out.
- This causes the harsh breath sounds, wheeze and crackles heard on auscultation when listening to a bronchiolitic baby’s chest.
presentation of bronchiolitis
- Coryzal symptoms. These are the typical symptoms of a viral upper respiratory tract infection: running or snotty nose, sneezing, mucus in throat and watery eyes.
- Signs of respiratory distress
- Dyspnoea (heavy laboured breathing)
- Tachypnoea (fast breathing)
- Poor feeding
- Mild fever (under 39ºC)
- Apnoeas are episodes where the child stops breathing
- Wheeze and crackles on auscultation
