Bronchiolitis Flashcards
(21 cards)
What is bronchiolitis?
Inflammation and infection in the bronchioles - small airways of the lungs.
What is the most common cause of bronchiolitis?
Usually caused by a virus. Respiratory syncytial virus (RSV) is the most common cause.
When is bronchiolitis common and in what age group?
In winter. Generally occurs in children <1 year, most common in children <6 months. Can rarely be diagnosed in children up to 2 years old, particularly in ex-premature babies with chronic lung disease.
What is the difference between the effects of a virus on adults and babies?
In adults, the swelling and mucus are proportionally small, having little noticeable effect on breathing. In infants, even the smallest amount of inflammation and mucus has a significant effect on their ability to circulate air.
What are the effects of bronchiolitis on a baby’s breathing?
Causes harsh breath sounds, wheeze, and crackles.
How will a baby with bronchiolitis present?
- coryzal symptoms - runny nose, snotty nose, sneezing, mucus in throat, watery eyes
- signs of resp distress
- dyspnoea
- tachypnoea
- poor feeding
- mild fever - under 39 degrees (if high grade fever, suspect smth else)
- apnoeas - episodes where the child stops breathing
- wheeze and crackles heard on ausculation
What are some signs of respiratory distress?
- raised RR
- use of accessory muscles - SCM, abdominal and intercostal muscles
- intercostal and subcostal recessions
- nasal flaring
- head bobbing
- tracheal tugging
- cyanosis
- abnormal airway noises
What abnormal airway sounds can you hear?
Wheezing, grunting, stridor.
What is wheezing?
Wheezing is a whistling sound caused by narrowed airways, typically heard during expiration.
What is grunting?
Grunting is caused by exhaling with the glottis partially closed to increase positive end-expiratory pressure.
What is stridor?
Stridor is a high-pitched inspiratory noise caused by obstruction of the upper airway, for example in croup.
What investigation can be used to confirm the cause of bronchiolitis?
Nasopharyngeal aspiration.
What is the course of RSV?
- bronchiolitis usually starts as an URTI with coryzal symptoms
- half get better spontaneously
- other half develop chest symptoms over the first 1-2 days
- symptoms worst on days 3/4 and last 7 to 10 days total
- most pts fully recover within 2-3wks
What are infants with bronchiolitis more likely to have in childhood?
A viral induced wheeze during childhood.
When would you admit a baby with bronchiolitis?
- presence of grunting
- if parents are not confident in their ability to manage at home or difficult accessing medical help from home
- <3 months old or any pre existing conditions eg. premature, downs syndrome, CF
- 50-75% or less of their normal intake of milk
- clinical dehydration
- RR>70
- O2 <92%
- cyanosis
- moderate to severe resp distress - eg. deep recessions or head bobbing
- apnoeas
How do you manage bronchiolitis?
- ensure adequate intake - orally, NG tube, IV fluids
- saline nasal drops and nasal suctioning - help clear nasal secretions esp. prior to feeding
- supplementary oxygen - if o2 sats <92%
- ventilatory support if needed
- keep child upright as much as possible when awake - help them breathe easier
- children’s paracetamol to babies and children >2months old or ibuprofen to babies and children >3months old
What is used for ventilatory support in bronchiolitis?
- low flow oxygen
- high flow humidified oxygen via a tight nasal cannula (Airvo or optiflow)→ (air and oxygen) to oxygenate the lungs and prevent airways from collapsing
- continuous positive airway pressure (CPAP) → involves using a sealed nasal cannula to deliver much higher and more controlled pressure/PEEP
- intubation and ventilation → insert an endotracheal tube into the trachea to fully control breathing using mechanical ventilation
What are some signs of poor ventilation?
- assess ventilation with capillary blood gas - foot
- rising co2 - shows that airways are collapsed and can’t clear waste co2
- falling pH- shows co2 is increasing and they’re not able to buffer the acidosis that this creates = respiratory acidosis
- if also hypoxic = type 2 respiratory failure
What is used as prevention against RSV?
Palivizumab, a monoclonal antibody that targets RSV, given as a monthly injection for high-risk babies.
How does the prevention against RSV work?
- not a true vaccine as it doesn’t stimulating the infants immune system
- it provides passive protection by circulating the body until the virus is encountered → then it works as an antibody against the virus → activating the immune system to fight the virus
- the levels of circulating antibodies decreased over time, which is why a monthly injection is needed
What can be done to prevent bronchiolitis and spreading the virus?
Wash hands often, clean toys and surfaces, use disposable tissues, keep newborns away from colds, don’t smoke around the child.
