Croup, Epiglottitis or Foreign Body? Upper Airway Obstruction in Children

Inspiratory stridor: localisation before diagnosis

Inspiratory stridor indicates obstruction of the extrathoracic airway, which may be supraglottic, glottic or subglottic. In children, even minor mucosal swelling has a marked effect because the airway is small and resistance rises disproportionately as the radius decreases. In the prehospital setting, the definitive diagnosis is therefore less important than three questions:

• How threatening is the obstruction right now?
• What is the most likely cause?
• Which measure will do no harm?

In stridor in children in particular, well-intentioned interventions can turn partial obstruction into complete obstruction. Examples include agitating the child, inspecting the throat or changing the child's position.

Key signs compared

Croup (subglottic laryngitis)

Croup is the most common cause of acute inspiratory stridor in young children. The typical triad is barking cough, hoarseness and inspiratory stridor. Onset is often at night, with low-grade fever. Affected children usually do not appear seriously ill, but they may deteriorate markedly when agitated.

Epiglottitis in children

Epiglottitis in children has become rare since the introduction of Hib vaccination, but it remains life-threatening. It should still be considered in vaccinated children, and other pathogens can also cause it. Warning signs are:

• acute onset with high fever and a toxic appearance
• drooling and painful swallowing
• muffled speech
• absence of a barking cough
• typical posture: sitting upright, leaning forward, with the mouth open

In this setting, quiet stridor is not a reason for reassurance.

Foreign body aspiration

The following findings are suggestive:

• sudden onset with a coughing fit, gagging or cyanosis
• a typical situation, such as eating nuts or playing with small objects
• no fever and no prodromal symptoms

The history is often the most powerful diagnostic tool, although the event itself is frequently unwitnessed.

Other differential diagnoses

• Bacterial tracheitis: onset resembles croup, followed by rapid deterioration with a toxic picture and no response to croup treatment.
• Anaphylaxis with laryngeal or tongue oedema: allergen exposure, urticaria and cardiovascular involvement. According to ERC 2025, adrenaline (epinephrine) 0.01 mg/kg IM applies (max. 0.5 mg; 1 mg/ml solution), for example 0.12 mg (= 0.12 ml) at 12 kg [2].
• Retropharyngeal or peritonsillar abscess: fever and difficulty swallowing, with torticollis (retropharyngeal) or trismus (peritonsillar).

Assessing severity

Assessment is primarily clinical and should involve as little handling as possible. Warning signs of impending decompensation are:

• stridor at rest rather than only when agitated
• marked recession (suprasternal, sternal, intercostal)
• tachypnoea above the age-appropriate normal range
• increasing agitation or, with a worse prognosis, apathy and reduced consciousness
• cyanosis and falling oxygen saturation; SpO₂ is a late sign
• stridor becoming quieter due to exhaustion: an alarm signal, not an improvement

As a guide to respiratory rate, ERC 2025 and RCUK 2025 give the following normal ranges [2, 146, 150]:

• 1 year: 20–50/min
• 2 years: 18–40/min
• 4 years: 17–33/min
• 6 years: 16–29/min

Clinical scores such as the Westley croup score can help to structure the assessment and document progress. They do not replace the overall clinical impression.

Core principle: keep the child calm

Whatever the cause, stress should be minimised while spontaneous breathing is maintained:

• Leave the child in the position they have chosen, usually sitting on a caregiver's lap. Do not lay the child down.
• No throat inspection with a tongue depressor if epiglottitis is suspected.
• Defer venous access, blood sampling and other painful procedures unless they are immediately necessary for treatment.
• Offer oxygen only as tolerated, for example held in front of the child by the caregiver.
• Keep monitoring to the essentials. Pulse oximetry is usually tolerated.
• Communicate calmly with the child and parents, and keep the number of people in the room to a minimum.

Prehospital treatment

Croup in the emergency setting

• Systemic corticosteroids (e.g. dexamethasone or prednisolone) are considered first-line treatment. In a cooperative child, oral administration is usually sufficient and is less distressing than an injection. Follow the current paediatric guideline, the summary of product characteristics and local SOPs for dose and formulation.
• Nebulised adrenaline may be considered in moderate to severe cases. Its onset is rapid, but its effect is time-limited, and symptoms may recur. Monitoring in hospital is therefore required after inhalation. Dose according to the current guideline and summary of product characteristics.
• Cold or humidified air is traditionally recommended. Evidence for any effect is limited, and it must not delay drug treatment.
• Give oxygen for hypoxaemia.
• The following favour transport to hospital:
  • persistent stridor at rest
  • recession
  • hypoxaemia
  • the need for adrenaline inhalation
  • an uncertain home situation
  • diagnostic doubt

Suspected epiglottitis

Airway management is not the prehospital priority. The aim is rapid, gentle transport:

• Transport the child sitting up, accompanied by the caregiver, without invasive procedures.
• Pre-alert the receiving hospital early so that anaesthesia and ENT or paediatric surgery are ready.
• The airway is ideally secured under controlled conditions in the operating theatre, with a surgical airway available as an option.
• Antibiotic therapy is started in hospital once the airway is secured or the child is stabilised. The choice of agent follows the current guideline.

Foreign body

The deciding factor is how effective the cough is [2]:

• Effective cough: encourage coughing and do not intervene. Observe closely and bring the child to hospital, as bronchoscopic evaluation is usually required.
• Ineffective cough, child conscious: back blows and compressions according to the ERC 2025 paediatric algorithm. In infants, chest thrusts are used instead of abdominal thrusts.
• Unconsciousness: start resuscitation according to the PLS algorithm. During laryngoscopy, look for a visible foreign body and remove it with Magill forceps. No blind finger sweeps.

Limits of prehospital measures

Prehospital intubation of a child with severe upper airway obstruction is a high-risk procedure. The view is limited, the glottis is narrowed, and spontaneous breathing may be lost entirely. As long as the child is breathing spontaneously and oxygenated, prompt transport is usually the safer option.

If respiratory arrest or complete obstruction occurs:

• Bag-mask ventilation using a two-person technique, an oropharyngeal (Guedel) airway and PEEP if needed. This is often possible even in epiglottitis, although the evidence is based mainly on case reports.
• Supraglottic airway devices are of limited effectiveness in supraglottic swelling or subglottic obstruction.
• Intubation: According to ERC 2025, cuffed tubes are recommended for all children. The formula 3.5 + age/4 gives, for example, an internal diameter of 4.0 mm at 2 years of age [2]. If swelling is present, have smaller tube sizes ready as well. Limit cuff pressure according to the manufacturer's instructions.
• Weight: If the actual weight is not known, the APLS formula provides an estimate: for ages 1–5 years, 2 × age + 8 kg [148].
• Emergency cricothyroidotomy: This is technically difficult in small children because of their small anatomical structures. Evidence for needle and surgical techniques is limited. It remains a last resort according to the local algorithm.

Structured preparation reduces the burden in this situation. This includes equipment in several sizes, clearly assigned roles and a weight-based dose overview, such as the paediatric emergency table in the compendium.

Key messages

• Inspiratory stridor indicates extrathoracic obstruction. The history distinguishes between infection, acute toxicity and an aspiration event.
• Keep the child calm and in their chosen posture. Do not inspect the throat with a tongue depressor if epiglottitis is suspected.
• In croup, corticosteroids are first-line treatment and nebulised adrenaline is the escalation step. Dose according to the current guideline and summary of product characteristics.
• In suspected epiglottitis, transport gently, pre-alert early and secure the airway in hospital.
• For a foreign body, choose the approach according to the effectiveness of the cough, as per ERC 2025.
• Stridor that becomes quieter and apathy are signs of exhaustion, not improvement.

References

• [2] Djakow J, Turner NM, Skellett S et al. European Resuscitation Council Guidelines 2025 Paediatric Life Support. Resuscitation 2025;215 Suppl 1:110767.
• [146] Resuscitation Council UK. Paediatric advanced life support algorithm – 2025 Resuscitation Guidelines sowie Paediatric Life Support Guideline 2025, Tabelle 1 „Approximate normal values“.
• [148] Advanced Life Support Group (ALSG). Advanced Paediatric Life Support (APLS) – A Practical Approach to Emergencies. Altersformeln zur Gewichtsschätzung.
• [150] Fleming S, Thompson M, Stevens R et al. Normal ranges of heart rate and respiratory rate in children from birth to 18 years of age: a systematic review of observational studies. Lancet 2011;377:1011–1018.

This article does not replace clinical judgement in the individual case or the current summary of product characteristics and guidelines.