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Croup
Bronchiolitis
Acute Wheeze or Asthma in Paediatrics
Inhalers for Adults with Asthma
Greener Inhaler Prescribing
Bi-Level NIV S/T Guidelines for CCU Phase
Bi-Level NIV S/T Guidelines for ED Phase
Chronic Cough Pathway
Paediatric Bronchiolitis
Exacerbation of COPD
Chronic Obstructive Pulmonary Disease
Legionnaires Disease
Interstitial Lung Disease
Oxygen Therapy
Acute Asthma
Pleural Effusion
Spontaneous Pneumothorax
Community Acquired Pneumonia (CAP)
Breathlessness with Abnormal CXR
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Croup
Last updated 31st January 2024
Definition
- Croup, also called viral laryngotracheitis, is an inflammation of the larynx and trachea secondary to a viral infection.
- Based on its presenting symptoms Croup can be defined as a syndrome consisting of cough, stridor, hoarseness and varying degrees of difficulty breathing.
Background
- Croup affects the larynx and trachea, and sometimes the inflammation extends into the bronchi.
- It is usually caused by parainfluenza 1 virus, which peaks every 2 years in the Autumn.
- Other viral aetiologies include influenza, adenovirus, metapneumovirus, RSV and mycoplasma.
- Children aged 6-36 months are most susceptible to croup because of their smaller airways.
- Interestingly, a family history of croup increases risk of infection four-fold, whilst males are slightly more prone to it than females – this is likely due to slight anatomical variation in the respiratory tract between female and male infants.
- Whilst generally considered a self-limiting illness and benign in most cases, croup can rapidly become life-threatening with airway obstruction. Only 5% of children are hospitalised, whilst 0.3% of children require a period of intubation. The mortality rate is low at 0.5% of those who are intubated.
- Volume of stridor does not correlate with degree of airway obstruction. Because children have small airways a slight level of inflammation can significantly reduce their airway diameter leading to rapid deterioration.
Presentation
- Typically, there is a preceding coryzal illness with croup developing over several days.
- The symptoms are classically worse at night and typically last between 3 and 5 days but can last up to a week.
- Croup usually causes:
- Harsh barking cough (“seal-like”)
- Stridor (due to subglottic tracheal inflammation causing partial airway obstruction)
- Hoarse voice. It often is worse at night/early hours of the morning – and that is most common time for presentation of respiratory distress.
- Key points in history:
- Duration of symptoms
- What they were doing prior to onset of stridor
- Any ill contacts
- Immunisation history (if not Hib vaccinated – think of epiglottitis)
- Red flags in the child with stridor include:
- Acute/sudden onset
- Sore throat
- Toxic-looking
- Drooling
- Systemic signs (GI upset, hypotension, urticaria)
- Key differentials for the child with stridor include – anaphylaxis, acute epiglottitis, bacterialtracheitis, foreign body.
Assessment
- Croup is predominantly an airway problem and observation followed by intervention with minimal examination is usually sufficient initially.
- The child will usually adopt a position to limit their airway obstruction when sitting on parent/carer’s knee – it is important not to interfere with this.
- Limit examination of the child as increasing their stress increases stridor and respiratory distress.
- Do not attempt ENT examination or cannulation unless absolutely essential – and only once anaesthetic support/senior present.
- The Westley croup score is validated and commonly used in clinical practice (Table 1). Children with croup can be divided into four levels of severity:
- Airway
- Usually have stridor – stridor at rest is indication for nebulised adrenaline
- A quiet stridor or stridor at rest that then ceases is extremely concerning for impending airway obstruction→move to resuscitation bay and inform senior
- Keep calm, keep the parent and child calm
- Alert senior to presence of any airway concerns
- Breathing
- Assess and record RR and SaO2 whilst minimising distress
- If acute respiratory distress or cyanotic→move to resuscitation bay and inform senior
- Provide oxygen if hypoxic – if the child will not tolerate a facemask hand it to the parent for wafting oxygen
- If able listen to chest for wheeze, to rule out other causes of hypoxia/respiratory distress
- Circulation
- Assess and record HR and central capillary refill time
- BP measurement is usually too distressing
- If shocked → more to resuscitation bay and alert senior
- Disability
- If any concerns about GCS for example drowsy or lethargic alert senior
- When they are more settled check BM – this can increase agitation and unless essential can be left until after stridor is dealt with
- Exposure
- Assess and record temperature
- After initial management undertake thorough history and examination of child.
Management
- Children with croup should be made comfortable and care should be taken to avoid agitating the child, such as using a non-contact form of oxygen delivery e.g. allowing the child’s care-giver to deliver oxygen using a ‘wafting’ technique.
- Oxygen should be administered to any child with oxygen saturation <92% on air.
Medication Treatment
Medication | Dosage | Guidance | Evidence |
---|---|---|---|
Adrenaline | Treatment is with 0.5mL/kg of 1:1,000 concentration to a maximum dose of 5mL | Nebulised adrenaline is only used in children with severe and life-threatening croup. Adrenaline does allow time for an experienced team including a senior anaesthetist to be gathered as well as rapidly improving the patient's distress | Double blind randomised control trials of this treatment demonstrate an improvement within 30min and last up to 2 hours. As the effect wears off, the child's symptoms return to base line level, however a proportion of children deteriorate even further. |
Dexamethasone | - Oral dexamethasone 0.15 mg/kg (Max dose 4mg) - Can be given IV or IM Max dose (6.6mg) - There is no difference in efficacy between oral and intramuscular dexamethasone. | There is evidence that a dose of 0.15mg/kg leads to the reduction in croup scores, admission rates and length of stay in hospital | In children with severe or impending respiratory failure, there is an absolute risk reduction of 1.1% in the rate of intubation |
Budesonide | 2mg of nebulised budesonide | If the child is vomiting nebulised budesonide can be used. However, nebulised budesonide can agitate the child whilst being delivered. |
Monitoring
- The respiratory rate, work of breathing, oxygen saturation and pulse rate should be carefully monitored.
- The work of breathing, respiratory rate, volume of stridor and pulse rate should decrease if the treatment is working.
Prognosis
- Despite early treatment of croup with steroids, some children do not respond and can deteriorate. Nebulised adrenaline causes a dramatic short term improvement in symptoms but in some patients there is a rebound effect with rapid deterioration.
- Referral to a senior paediatric trained doctor and early consideration of PICU involvement is essential.
Discharge
- Children with mild croup normally can be discharged home following a single dose of dexamethasone. Children who are discharged home, advice must be given to a parent and documented in the notes
- Children presenting with moderate croup need to be observed for a minimum of four hours following a dose of dexamethasone and then re-assessed on a paediatric ward. Those with severe croup must be admitted into hospital.
Safety Alert
- 20% of children presenting with acute stridor do not have croup. If an alternative diagnosis is not sought then serious differentials could be missed.
- In children who present with a sudden onset of stridor a foreign body should be considered.
- Children with epiglottitis should not have the oropharynx examined as this can cause total airway obstruction. Diagnosis is clinical and confirmed when the child is intubated.