Respiratory system

Fifth stage

د.فارس الصواف

Pediatric

Lec-2 16/11/2016

Respiratory

Acute bronchitis

Very common in neonate.

Commonly viral, rarely bacteria.
Preceded by upper respiratory tract infection. Followed by dry cough.
Older children may experience chest pain exacerbating by coughing.

Investigation No need

CXR may be normal or show peri-bronchial thickening.

Treatment

No need for hospital admission. Supportive measure:
1. Humidification (steam inhaler) 2. Rest
3. Change position

4. Expectorant not helpful 5. Antibiotic not indicated

6. Cough suppressant not helpful.

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Pneumonias

Definition

Inflammation of the lung parenchyma due to infectious and non-infectious agents.

Etiology

Age
Bacteria
Virus
other
Neonate
Group B streptococci* G -ve bacilli
E. coli
Streptococcus pneumoniae H.influnzae Chlamydia trachomatis
3 months
Streptococcus pneumoniae H.influnzae
RSV * Rhinovirus Influenza virus
Chlamydia trachomatis
4months - 4 years
Streptococcus pneumoniae
Group A streptococci Staph. aureus
RSV*
>5 years
Streptococcus* pneumoniae H.influnzae Mycoplasma pneumoniae
Influenza virus RSV
Legionella pnemophilia Chlamydia pneumophilia
Age
Bacteria
Virus
other
Neonate
Group B streptococci* G -ve bacilli
E. coli
Streptococcus pneumoniae H.influnzae Chlamydia trachomatis
3 months
Streptococcus pneumoniae H.influnzae
RSV * Rhinovirus Influenza virus
Chlamydia trachomatis
4months - 4 years
Streptococcus pneumoniae
Group A streptococci Staph. aureus
RSV*
>5 years
Streptococcus* pneumoniae H.influnzae Mycoplasma pneumoniae
Influenza virus RSV
Legionella pnemophilia Chlamydia pneumophilia
* most common m.o in that age group


N.B:

in neonate, there is no viral infection only bacteria. The neonate catch group B streptococci from birth canal during delivery and G -ve bacilli from mother rectum.
Virus cause bronchopneumonia (generalized) Bacteria cause lobar pneumonia (localized)

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Symptoms and signs 1. Respiratory distress 2. Dyspnoea

3. Tachypnea

4. Grunting (pathognomonic) 5. flaring nostrils

6. tachycardia 7. fatigability
8. interested recession, sub costal retraction 9. fever, malaise, vomiting, delirium, anxiety
10.lower lobe pneumonia may cause abdominal pain

11.upper lobe pneumonia may cause CNS manifestation (Neuk stiffness.

physical finding:

1. diminished breath sound

2. scattered rhonchi & crackles 3. lobar consolidation
4. dull to percussion

5. increase diminished breath sound. 6. bronchial breathing

7. palpable liver due to downward displacement of the diaphragm or due to CHF 8. signs of CHF
9. abdominal distension (paralytic ileus)

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Differentiate between Bacterial and viral pneumonia

Bacteria

Virus

Fever

High

Slight


Respiratory symptoms

Severe

Less severe

Neurological symptoms

Present

Absent

Pleuritic chest pain

Present

Absent

WBC

Leukocytosis (PMN)

Lymphocytosis or normal

Onset

Abrupt and not preceded by URTI
Take few days and preceded by URTI

Chest

Lobar consolidation

Bilateral infiltration

Diagnosis

Culture

isolation

Investigation

From age and clinical history
Sputum for culture and serology not beneficial
Blood culture positive only in 10% in bacterial pneumonia
CXR may show lobar consolidation in bacterial pneumonia and bilateral infiltrate in viral pneumonia.


Staph pneumonia

Very severe, stormy, fatal course .

Respiratory distress, dyspnoea, bacteraemia, septicaemia toxic and may collapse.  High fever
affect young babies & may cause Broncho pulmonary fistula

CXR: characteristic may show pleural effusion, empyema, pneumatocele.

Treatment

Admission to hospital Oxygen

Hydration: IV fluid

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Parenteral antibiotic (Anti-staph.) give 2 antibiotic Flucloxacillin 100 mg/kg in two divided dose Or Clindamycin + Vancomycin.

Mycoplasma pneumonia

Atypical pneumonia
extra-pulmonary feature: fever, malaise, headache poor response to Penicillin
-ve culture, need Special culture
need specific investigation (cold agglutinin, PCR, Mycoplasma specific IgG level) Diffuse bilateral infiltrate
Age>5 years


Treatment

Azithromycin (10-20mg/ Kg) single dose for 7-10 days, fluoroquinolone also effective clinical improved in 3-6 days
Radiological improvement need 6-8 weeks
Antibiotics should be stopped once clinical improvement occur.

indication for Hospital admission for pneumonia

1. Multiple lobe opacity 2. Sickle cell anemia
3. previous cardiac or pulmonary disease 4. No response to oral antibiotic
5. Not compliant parent 6. Need O2
7. Baby <6 months
8. Severe respiratory distress. 9. Toxic
10.Poor oral intake 11.Vomiting 12.Dehydration 13.Immune deficiency

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Complications

Local spread: to intrathoracic structure (especially in Staph.aurues, Strept.pyogens and Strept.pneumoniae)


Pleural effusion Empyema
Pericarditis

Systemic spread: septicaemia Meningitis

Superlative arthritis Osteomyelitis

Slowly resolving pneumonia Causes

1. Bacteria (resistance) 2. Virus
3. Poor compliance 4. Empyema
5. Noxious M.O (T.B pneumonia) 6. F.B inhalation (bronchoscope)
7. Congenital tracheoesophageal fistula (barium swallow)
8. Cystic fibrosis (sweat chloride test + clubbing of fingers + malabsorption ) 9. Immune deficiency

Recurrent pneumonia

More than 2 pneumonia/year or > 3 pneumonia in his life. Causes : 1. Cystic fibrosis.
2. Sickle cell anemia.
3. As above in slowly resolving pneumonia

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Asthma Most common chronic disease in children.
Chronic inflammation of lung airway result in episodic attack of airway obstruction (bronchospasm) due to airway hyper responsiveness due to various immunological & non-immunological exposure triggers.

Common cause of morbidity.

Further episode worsens the condition.

Trigger

1. Exercises 2. Crying
3. Laughter

4. Hyperventilation

5. Common viral infection

6. Aero inhalant allergen (dust mite, melds, indoor allergen) 7. Season allergen (pollens)

8. Environment (tobacco smoking) 9. Air pollution
10.Noxious strong odour 11.Cold dry airs 12.Occupational allergen 13.Drugs (aspirin, B-blocker) 14.Additives

Pathology

Hyper responsiveness result in:

1. spasm (bronchospasm due to smooth muscle contraction ). 2. edema.

3. Excessive mucous secretions

All these lead to air way obstruction.

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Signs & symptoms

Intermittent dry cough Dyspnoea
Wheeze (expiratory) Chest tightness
+ve family history of atopy

Symptoms of asthma worse at night Physical findings: -

Wheeze.

Rhonchi, crepitation.

Diminished breath sound.


In sever inspiratory & expiratory wheeze & silent chest.

Differential diagnosis

1. Bronchiolitis due to RSV. 2. Foreign body inhalation 3. GERD
4. Mucociliary clearance disorder: cystic fibrosis & bronchiectasis 5. Vascular ring
6. Tracheomalasia

7. Pulmonary sequestration 8. Interstitial lung disease 9. Heart failure

10.Tracheoesophageal fistula 11.Immune deficiency 12.Anaphylaxis
13.Allergy

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Investigation Clinical

CXR: Normal or Hyperinflation, flat diaphragm, narrow mediastinum.

N.B: we do x-ray at first attack to exclude other DDx, unnecessary thereafter unless suspect complication (atelectasis, pneumothorax, pneumo mediastinum)

Pulmonary function test: objective measure to measure the degree of airways obstruction:


A. spirometry: FEV1/FVC ratio according to age, gender, height, ethnicity. Usually can do it after 6 years of age.

FEV1/FVS < 60 % .......... Severe obstruction

FEV1/FVS 60_80 % ...... Moderate FEV1/FVS > 80% ........... Mild

B. Peak expiratory flowmeter (PEF): Simple device, home used, at morning three attempts & take the highest attempt. Used to show response to bronchodilator

Skin prick test: in atopic

Complete blood picture: show eosinophilia

Sputum eosinophil

Level of IgE (RAST) Radio Allegro Sorbent Test.

Treatment Four keys:

1. Check-up: every 2-4 wks. until control achieved, then 2-3 times per years to maintain a good control.

2. Eliminate the triggers

3. Pharmacotherapy

4. Education: how to use inhaler, symptoms of disease, side effect of drug .

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Pharmacotherapy: two type of drugs

1. Long term controller drug 2. Quick reliever rescue drugs

Long term controller drug:

1. Inhaled corticosteroids (ICS) such as beclomethasone, betamethasone & budesonide dry powder inhaler, spacer, nebulizer, inhaler, rinse the month with water to prevent candidiasis or dysphonia.

2. Long acting inhaled B-against (LABA) salmeterol, formoterol.

3. Theophylline: bronchodilator & anti-inflammatory. Not used nowadays because of narrow therapeutic range and many drug interactions.

4. NSAID: promoline, nedocromil very effective for exercise 2-4 time daily

5. Leukotriene modifier: montelukast, zafirlukast


6. Anti IgE monoclonal antibodies: omalizumab

Quick reliever rescue drugs

1. Short acting B-agonist (SABA) salbutamol, terbutaline.

Side effect: tachycardia, tremor, hypokalaemia.

2. Short course systemic steroid: 1-2mg/kg/day orally for 3-10 days.

3. Anticholinergic: ipratropium bromide with SABA .

Step up -step down classification of asthma 1. Mild intermittent ≤ 2day/weeks
≤2 bad night /months

Rx: only reliever on need (best SABA).

2. Mild persistent: >2day symptom/week

>2 bad night /month

Rx: 1 controlled at regular base (low dose ICS) + reliever on need

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3. Moderate persistent: daily symptoms,

> 1bad night/week

Rx: 2 controllers (best low or moderate doseICS +LABA) + reliever on need

4. Sever persistent: continuous symptoms

frequent bad night

Rx : 3 controls ICS + LABA + short course oral systemic steroid

Three comorbid conditions make asthma difficult to control 1. Rhinitis

2. Sinusitis also called indirect triggers 3. GERD

Prognosis

35% recurrent wheeze and cough in the pre-school age. 2/3 of patient grow out of it in pre-teen ages.
1/3 continue as asthma in later childhood and adult.

Prophylaxis

Encourage breast feeding Discourage smocking
Good hygiene, active life style

Rural area better than urban area

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Complications Atelectasis

Respiratory failure

Pneumothorax & pneumomediastinum Death

Collapse

Severe asthma exacerbation (SAE) Status asthmaticus Risk factor

1. Male gender


2. Air pollution, tobacco smoking 3. Younger uneducated mother 4. Poverty
5. Crowding

6. Previous severe attack

7. Previous rapidly occurring attacks 8. Chronic wheezier
9. Poor compliance to drugs 10.Low birth wt. 11.Allergens

Symptoms and Signs

Dyspnea, tachypnea, use of accessory muscle of respirations, silent chest, inability to talk, excessive sweating, tripod position, pulsus paradoxus , poor air exchange, cyanosis ,respiratory muscle fatigue & respiratory failure & may die .

PSO2 <90 %

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Treatment

Admission to hospital (ICU)

 Oxygen (oxygen saturation should be above 92%) Hydration

CXR if there is complication (atelectasis, pneumothorax) Complete electrolyte may be abnormal.
SABA nebulizer every 20 min Systemic steroid
Monitoring


Ipratropium bromide, terbutaline, adrenaline 0.1 mg /kg

Aminophylline infusion 5mg/kg loading dose IV slowly for 30 min then 1mg/kg/hr infusion

Mg sulphate, Hilux

Mechanical ventilation

Discharge after 2-3 days but continue short rescue drugs and short course systemic steroid for 2-3 days.

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