Bronchiolitis Flashcards
What is bronchiolitis?
Viral infection of the bronchioles
Which virus commonly causes bronchiolitis?
respiratory syncytial virus
Which age group is most commonly affected by bronchiolitis?
< 2yo
Which seasons have higher incidence of bronchiolitis
Winter and spring
Describe the pathophysiology of bronchiolitis
Proliferation of goblet cells causing excess mucus production
IgE mediated type 1 allergic reaction causing inflammation
Bronchiolar constriction
Infiltration of lymphocytes causing submucosal oedema
Infiltration of cytokines and chemokines
The combination of mucus, oedema and increased cells in the bronchioles leads to a ball-valve effect resulting in hyperinflation, increased airway resistance, atelectasis and ventilation-perfusion mismatch
List some risk factors of bronchiolitis
Being breast fed for less than 2 months
Smoke exposure
Having siblings who attend nursery or school
Chronic lung disease due to prematurity
List the clinical features of bronchiolitis
Increasing symptoms over 2-5 days Low grade fever Nasal congestion Rhinorrhoea Cough Feeding difficulty
List the examination findings of bronchiolitis
Tachypnoea Grunting Nasal flaring Intercostal, subcostal or supraclavicular recessions Inspiratory crackles Expiratory wheeze Hyperinflated chest Cyanosis or pallor
Give the differential diagnosis of bronchiolitis
Pneumonia Croup Cystic fibrosis Heart failure Bronchitis
What investigations would you do for bronchiolitis?
Nasopharyngeal aspirate or throat swab - RSV rapud testing and viral cultures
Blood and urine culture if child is pyrexic
FBC
Blood gas (ABG) if severely unwell
Imaging - CXR
What features are seen on CXR in bronchiolitis
Hyperinflation Focal atelectasis Air trapping Flattened diaphragm Peri bronchial cuffing
Describe the management of bronchiolitis
Home or hospital
Supportive management - fluids, good nutrition and temperature control
When should an urgent referral to hospital be made?
Apnoea Child looks unwell Severe respiratory distress Central cyanosis Oxygen sats <92% RR >60 Inadequate fluid intake (50-75% usual volume) Clinical dehydration
What management should occur in hospital for bronchiolitis
Oxygen if sats <92%
Fluids via NG or OG tube if inadequate oral intake
CPAP if impending resp failure
Upper airway suctioning if there are upper airway secretions or apnoea
When should a bronchiolitis patient be discharged?
Clinically stable
Taking adequate oral fluids
Maintaining sats >92% for more than 4hrs
