Croup - GM Flashcards
another name for croup
laryngotracheobronchitis
what is croup
upper respiratory tract infection commonly caused by viral infection
what age does croup occur
aged 6months - 3 years old
croup presents primarily with
characteristic barking cough, inspiratory stridor, respiratory distress
which type of stridor does croup present with
inspiratory
pathophysiology of croup
upper respiratory tract infection inflames the mucosa in the larynx
this inflammation causes airway obstruction leading to turbulent airflow resulting in audible stridor
poiseuille’s law
resistance to laminar airway increase in inverse proportion to the fourth power of the radius of the lumen
therefore, a small reduction in airway radius (due to inflammation and secretions) dramatically increases resistance to airflow and therefore work of breathing
croup is most commonly caused by
parainfluenza viruses and respiratory syncytial virus (RSV) but can be caused by other viruses
risk factors
age: croup most commonly occurs in children aged 6-36 months
family history
male (the male:female ratio is 1.4:1)
congenital airway narrowing
hyperactive airways
acquired airway narrowing
features of croup on history
upper respiratory tract symptoms including coryza and nasal congestion/discharge
fever
hoarse voice
coryza
barking cough (often described as seal-like)
inspiratory stridor
symptoms worse at night
no history of inhaled foreign body
approach of clinical examination
clinical examination should not agitate the child as this will worsen respiratory distress
guidelines recommend minimal handing of the child
throat exmination is rarely required but may be considered if the diagnosis is unclear, but not if epiglottitis is suspected
ABCDE assessment
further exmination can be performed once the situation is stabilised, which may include ENT examination, examination of cervical lymph nodes, lung auscultation and assessment of rashes
typical clinical findings of croup
increased work of breathing: intercostal and sternal recession
agitation: in severe croup
lethargy: in severe croup
clinical severity of croup
loudness of stridor is not an indication of severity of croup
differential diagnosis
epiglottitis
upper airway abscess
foreign body inhalation
allergic reaction / anaphylaxis
injury to the airway
congenital airway anomalies (eg. laryngomalacia, tracheomalacia)
bronchogenic cyst
bacterial tracheitis
early Guillian barre syndrome
how to tell epiglottitis apart from croup
presents without the barking cough seen in croup, child will appear anxious, pale and toxic.
difficulty swallowing is associated with increased rolling, fever and typically patients sit in an upright position
these children should have minimal handling, do not examine the mouth
how to tell upper airway abscess apart from croup
such as peritonsillar, paraapharyngeal and retropharyngeal. may present with fevers, stiff neck, torticollis, drooling or hot potato voice
absence of barking cough
how to tell foreign body inhalation apart from croup
sudden onset stridor and respiratory distress with Hx of choking
may also present with a barking cough and stridor depending on the location of the obstruction
importantly, there will be no fever
diagnosis of croup
clinical diagnosis, does not require investigation
routine viral testing is not required as it does not change management
chest x-ray not indicated (except for those considered for paediatric critical care admission)
chest x-ray in croup
not required, but will demonstrate the steeple sign due to subglottic narrowing
general rules for management
all children whopresent to emergency department with croup should receive corticosteroids
additional treatment depend on severity and may include nebulised adrenaline
croup is self-limiting, management aims to reduce severity and avoid need for intubation
if the croup seems life threatening
assessing severity of symptoms
severe croup looks like
stridor at rest
marked recession
tracheal tug
drooling
pale or mottled
moderate croup looks like
stridor at rest
mild recession
+/- tracheal tug
child interested in surroundings
mild croup looks like
barking cough
hoarse cry
stridor soft or absent
no recession or tracheal tug
management of severe croup
nebulised adrenaline - can be repeated after 15 minutes
oxygen to correct hypoxia if present
dexamethasone
observe for minimum of 3 hours following dose of adrenaline, due to risk of rebound symptoms when adrenaline wears off
management of moderate croup
dexamethasone oral
observe closely over next hour
management of mild croup
oral dexmethasone
discharge home with written advice sheet
why do you have to monitor after nebulised adrenaline
due to risk of rebound symptoms after the adrenaline wears off
when to admit to hospital
severe croup
moderate to severe croup but with deterioration or repeated doses of adrenaline
toxic appearing child
oxygen requirement
inability to tolerate oral fluid intake
complications of croup
most children should resolve within 3 days
complications are uncommon but may include:
- secondary bacterial infections (including bacterial tracheitis, bronchopneumonia and pnuemonia)
- post obstructive pulmonary oedema
- pneumothorax
- pneumomediastinum
resuscitation
transfer to resus room and activate resus team
give nebulised adrenaline immidiatley
administer high flow oxygen (via non-rebreather mask)
call PCC, anaesthetics, and ENT assistance
prepare for intubation (ideally done in operating theatre by anaesthetic and ENT teams)
all severe and life threatening croup should be discussed with
discussed with a senoir doctor +/- the paediatric critical care unit
child should be admittd under general paediatric team
how to use corticosteroids for croup
steroids start working by 30 minutes and reduce time in hospital, instances of intubation and reduce likelihood of relapse after discharge
steroid therapy treats stridor, but does not resolve underlying viral symptoms
a single dose is usually all that is required for mild to moderate croup
which corticosteroid should ideally be used for all croup presentations
dexamethasone PO
which corticosteroid can you use if dexamethasone is not available
prednisolone PO
which carticosteroid can you use if oral steroids are not tolerated
Dexamethasone IM
which corticostroid should you use for severe cases of croup (ie. PCC candidates)
dexamethasone IV
discharge criteria for the child with croup
clinically improved
steroids recieved
no stridor at rest
no other clinical or social concerns
