Lower Respiratory Tract Obstruction Flashcards
What can intra-thoracic airway be divided into?
- Larger airways
2. smaller airways
What are the larger airway causes of obstruction?
Foreign body aspiration
Tracheomalacia
TB gland obstruction
What are the smaller airway causes of obstruction?
- Bronchiolitis
- Asthma
- Bronchiectasis
- Cystic fibrosis
- Cardiac failure
- Pneumonia with eosinophilia
Who are the typical ‘transient wheezers’?
- small for gestational age and born to mothers that smoked during pregnancy
- the wheezing usually occurs after a viral infection and disappears after 3 years
What organisms causes acute viral bronchiolitis?
- RSV in 75%
- Adenovirus
- metapneumovirus
When does acute viral bronchiolitis usually occur?
In winter
At what ages does acute viral bronchiolitis usually occur?
2-6 months but it can occur in children up to 2 years
What is the pathophysiology of acute viral bronchiolitis?
A mucous plug occurs which causes air trapping and hyperinflation of the lungs
Atelectasis can also occur because the air is able to get into the alveoli but it cannot go out causing collapse
What are the clinical signs of acute viral bronchiolitis?
- Starts as a upper airway infection that later becomes lower airway obstruction
- Coughing
- Wheezing
- Tachypnea
What can we expect on chest X-ray in bronchiolitis?
- Areas of air trapping
On examination what are the signs we can expect in a child with bronchiolitis?
- Barrel chest
- Hoovers sign
- Palpable liver-displaced downwards
- Wheezing
- Widespread crackles
- Decreased cardiac dullness
What organism will cause the most severe form of bronchiolitis?
Adenovirus
What is the management of bronchiolitis?
- Supportive
- oxygen nasal prongs with CPAP if needed to relieve hypoxia
- trial of nebulised salbutamol
- give oral feeds unless severely tachypnea if and distressed
- antibiotics are only indicated if there is possible evidence of secondary bacterial infection
What is bronchiolitis obliterans?
- bronchiolitis caused by organism adenovirus
- much more severe and treatment requires high concentrations of supplemental oxygen, and ventilation
- the children remain symptomatic for months after the acute attack with wheezing, air trapping and widespread crackles
How do we diagnose bronchiolitis obliterans?
On CT-we usually see localized areas of air trapping with decreased perfusion
What is the clinical definition for asthma?
Any child of any age presenting with >3 episodes of wheezing and/or dyspnea that responds to a bronchodilator has asthma until proven otherwise
What age is asthma more common in?
2-5 years
What is the pathophysiology of asthma?
- Smooth muscle spasm
- Inflammation with eosinophilia/lymphocyte infiltration
- Mucus plugging of small airways
How do we diagnose asthma?
- Family hx
- Patients symptoms
- Lung function tests
- Response to bronchodilator
- Allergy testing
What are the signs of allergic rhinitis/atrophy?
- Shiners
- Mouth breathing
- Allergic salute
What are the typical signs of asthma?
- Repeated episodes of tigh chest or wheezing
- Cough especially at night
- Signs better after bronchodilator
- Early morning waking
- Wheeze or cough after physical activity
What are the signs of an asthma attack?
- Anxiety and restlessness
- Tachycardia
- Intense wheezing on auscultation
What is mild intermittent asthma?
- Occurs once a month
- No night symptoms
- Normal lung function tests
- No recent hospital admission
What is persistent asthma?
- Occurs during the day and night
