Pediatirc/ Asthma

General notes:
 10 -15% of school age children have by asthma.
 It is the commonest chronic disease in children.
 It is a common cause of hospital admission, emergency admission, absent from school,
doctor visit, and have high risk of death.
 Asthma is chronic inflammatory condition of airway lead obstruction of airways due to
hyper -responsiveness to trigger factors ( allergens).
 The word asthma give bad impression to the parents ((so don’t say asthma)).

Etiology: It is multifactorial disease :

 Genetic, biological, environmental.
 Family history of asthma in one or both of parents or any other allergic conditions: al lergic
rhinitis, eczema, frequent sneezing, atopy.
 Triggers of asthma:
o exercise
o stress
o crying
o laughter
o hyperventilation
o Viral infection: RSV  commonest trigger is viral infection.
o inhalant allergens (animal danders, pollens, house dust mites)
o Tobacco smoke
o Cold air dry exposure.
o Air pollutants.
o Strong odors.
o Anxiety.
 Conditions worse asthma (precipitate the attack):
o Sinusitis.
o Allergic rhinitis.

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o GERD :which is very commo n in children & renders the management difficult, the

mechanism explain this as f ollows: -
1. Recurrent emesis  aspiration.
2. Vagally stimulated bronchospasm (reflux) .

Pathology:

 Inflammation.
 Allergic condition  IgE and eosinophilis .
 Edema.
 Thick secretion.
 Collagen deposition.
 All lead to airway obstruction.

Clinical features:

1. Cough .
2. wheeze (intermittent, inspiratory and expiratory)
3. Dyspnea.
4. Chest tightness.
 All the above features are worse at night.
 In the day, the symptoms are more in physical activity (exertion).

Clinical exam:

 Tachypnea.
 Retractions.
 Decrease breath sounds.
 Inspiratory & expiratory wheeze.
 Silent chest
 Crackles (because of increased production of secretion due to mucus gland hypertrophy).
 Note  no clubbing in asthma (but in CF there is clubbing).
 In asthma  hyperventilation (acidosis) and hypoventilation (alkalosis)

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Signs of severity:

 Tachypnea
 Tachycardia
 Inability to talk
 Diaphoresis
 Pulsus paradoxus (may be absent)
 Tripod position
 Altered mental state
 Cyanosis
 Wheezy chest or silent chest.
 Diminished breath sounds.
 No air entry or exchange.

Investigations:

 Chest X -ray ( CXR ):
o Is indicated in:
1- First attac k to exclude other DDx (no need to repeat CXR in the other attack).
2- If we treating the patient with his good compliance but the patient condition still
NOT stable, perform CXR to diagnose complications or to exclude other Diseases.
o Findings like pneumothorax, atelectasis, mediastinum widening
 Peak expiratory flow (PEF) :
o Very important but is ind icated in children who are 6 years old age o r greater,
because it needs cooperation.
o Told to child to blow forcefully and take the highest readings after 3 att empts, and
Compa re the results according to AGE , SEX , and ETHINICITY .
o PEF test  easy, cheap, done at home.
o FEV1/FVC must be >80%  it means good control of asthma.
o If between 60 -80  it is fairly controlled.
o If <60%  poorly controlled (severe attack).
o FEV1 is important to change the treatment.
 Complete blood picture (CBP): eosinophils >4% is heralded for persistent asthma.
 Sputum (for eosinophils)  not necessary
 Blood culture (it is NOT so necessary to be done)
 Prick skin test  important test for children, any suspected allergens injected SC on
for earm, till development of wheal (p ositive test ).

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 Measuring of IgE by RAST test ( radio allergo sorbent test).

 Electrolyte and blood gases  done in severe asthma.

Differential Diagnoses:

 GERD.
 TEF (H -type).
 Foreign body inhalation.
 Bronchiolitis.
 Interstitial lung disease.
 Broncho -pulmonary dysplasia (or mycosis).
 Cystic fibrosis (rare) .

Treatment of asthma:

1- Checkup asthma  every 2 -4 weeks until you achieve good control then do checkup 2 -4
times per year.
2- Control of triggers  precipitating factors and co -morbidity (treat them).
3- Pharmaco -therapy  long term control therapy (controller) – quick relief therapy
(reliever or rescue ).
4- Education  of child and parents, action plan, how to take steroid at home, how to use
drugs, house cleaning.

Types of inhalers:

 Metered dose inhaler  suitable for older children.
 Spacer  for younger children.
 Dry powder inhaler
 Nebulizer (the best one but needs electricity).

Long term control therapy (controller):

1- Inhaled corticosteroids:
 Examples: beclomethasone, fluticasone, budesonide.

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 Good ant -inflammatory agents.

 Good in control of acute attacks.
 After use of inhaled corticosteroids  wash child mouth to get loss side effect like
dysphonia and oropharyngeal candidiasis (for low dose) and systemic steroid side
effects (for high dose).
2- Inhaled long acting B agonist (LABA):
 Salmeterol (delayed onset of action) and formoterol (start after 10 min)
 Formoterol is better.
 Duration of action 12 hours.
 Not use in acute attacks.
 Give it twice daily.
3- Theophylline:
 Old drug, out of use.
 Narrow therapeutic window.
 Variation of effects.
 A lot of side effects (hypotension, seizure).
 Use sustained release theophylline.
 Has bronchodilator and anti -inflammatory effects.
4- NSAID:
 Like cromolyn and sodium nedochrolene and Ental.
 2-5 times per day.
 No side effects.
5- Leukotrienes antagonists (modifier):
 Montelukast  above 1 year age.
 Zafirlukast  above 5 years age.
 Ziluten  above 10 years age.
 All give as chewable tablets (4 -5 mg/day) at night.
6- Anti -IgE:
 Like Omalizumab .
 May produce anaphylaxis.
 They are monoclonal antibodies against IgE  block IgE binding site.
 Is given for those >12yrs old.

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 It is expensive and NOT available.

 M ay produce anaphylaxis .
7- Anti - interleukin 5:
 It is monoclonal antibodies.
 Like mepolizumab .

Quick relief therapy (reliever or rescue):

1- Short acting B agonist (SABA).
 Inhaled  Side effects less than oral one.
 Side effects like tachycardia, hyperkalemia, tremor.
 It is bronchodilator.
 Like salbutamol, albuterol .
 0.5 ml  for less than 5 years // 1 ml  for more than 5 years ((only ml, not ml/kg)
 Very effective.
 Give it with 2 ml of normal saline  use nebulizer .
 Oral is as effective as parenteral .
2- Systemic steroids:
 Used in severe or moderate asthma.
 Give short c ourse 3 -10 days or 5 -7 days .
 No need for tapering.
 They are the best anti -inflammatory .
 You can give corticosteroids for 2 weeks without tapering.
 Side effects  hypertension, short stature, weight gain, hypokalemia, cataract,
glaucoma, reduced immunity.
 Under -utilization of steroids lead to bad prognosis.
3- Inhaled anti -cholinergic:
 Like ipratropium bromide.
 Used with SABA.

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Stages of asthma:

 Mild intermittent :
o Less than 2 days symptoms / week.
o Less than 2 bad nights / month.
o Rescue treatment only, no need for controllers.
 Mild persistent :
o More than 2 days symptoms / week.
o More than 2 bad nights / month.
o Rescue treatment + one controller agent (low dose inhaled CS) .
 Moderate persistent :
o Daily symptoms / week .
o More than 1 bad night / week.
o Rescue treatment + 2 controllers ( inhaled CS & theophylline ).
 Severe persistent :
o Frequent night & days symptoms.
o Rescue treatment + 3 controllers (High dose inhaled CS + LABA +/ - systemic steroids).

Prognosis:

 Asthma is recurrent disease.
 Two third of child  treat completely.
 One third of child  still with adult asthma.
 Normal PaCO2 is b ad ominous sign that indicates r espiratory failure (normal PaCO2
should be<40).

Status asthmaticus:

 History of severe attacks.
 Low birth weight.
 Occur in male gender.
 Treatment:
 Admission to ICU  Monitoring  two r escue treatment  Inhaled and systemic
corticosteroids  aminophylline infusion  Mg sulfate (IV 75 mg/kg)  ipratropium
bromide  terbutaline  adrenaline (0.01 mg/kg) SC or IM (very painful)  Ventilator.
 No need for  Oral beta 2 agonist / Ketotifen (anti -histamine) / Antibiotics / Oral
bronchodilators (side effects).