This document provides clinical guidance for all staff involved in the care and management of children aged one to five years presenting to an Emergency Department (ED) in Queensland with a wheezing illness.
This guideline has been developed by senior ED clinicians and Paediatricians across Queensland, with specialist input from Paediatric Respiratory staff, Queensland Children’s Hospital, Brisbane. It has been endorsed for use across Queensland by the Queensland Emergency Care of Children Working Group in partnership with the Queensland Emergency Department Strategic Advisory Panel and the Healthcare Improvement Unit, Clinical Excellence Queensland.
Guidance for wheezing children aged less than one year can be found in the Bronchiolitis – Emergency management in children Guideline. For wheezing children over five years refer to the Asthma – Emergency management in children Guideline.
Wheeze is a continuous high-pitched sound with musical quality emitting from the chest during expiration1 often associated with increased work of breathing2. Pre-school wheeze is also referred to as reactive airways disease. Wheeze is a very common ED presentation in children that is usually caused by intercurrent viral infection or other environmental triggers. Evidence suggests that up to 30% of children will have at least one episode of wheezing prior to their third birthday,3 over half will have more than one episode4 and 60% will stop wheezing by six years of age.
The term asthma is not commonly used to describe a wheezing illness in pre-schoolers, as this cohort is heterogeneous and includes a spectrum of children from those with an episode of viral-induced wheeze to those with asthma1. Pre-schoolers commonly experience wheeze during discrete time periods, often in association with clinical evidence of viral infection, with symptoms absent between episodes. Repeated episodes tend to occur seasonally and it usually declines over time, improving by six years of age.
Viral infection is a common trigger but other triggers include tobacco smoke, allergen exposure, mist, crying, laughter and exercise.
Risk factors for a future diagnosis of asthma include:
Several clinical prediction models for future risk of asthma have been developed based on family history, presence of atopy, indirect evidence of airway inflammation (such as peripheral blood eosinophil count) and severity of pre-school wheeze. Further work in this area is needed before any conclusions can be drawn5.
The purpose of assessment (history taking and physical examination) is to:
Studies have shown while physicians can accurately identify wheeze, parents may not be able to do so.2 Ideally, the presence of a wheeze should be confirmed by a clinician.
History should include specific information on:
All health professionals have a role in advocating for their patients by advising parents about the increased risk of wheezing associated with parental smoking.
The child should be assessed within the time frame recommended by the triage category. General appearance, mental state and level of respiratory distress are the most important markers of illness severity.7 Signs of respiratory distress in pre-school children include accessory muscle use, abdominal breathing, intercostal recession, subcoastal recession and tracheal tug.
Wheeze may be absent due to severe airway obstruction or extreme fatigue. A “silent chest” (chest with little or no breath sounds) is a warning sign of life-threatening respiratory failure and/or respiratory arrest.
| Mild | Moderate | Severe | Life -threatening |
|---|---|---|---|
| Normal conscious state | Normal conscious state |
Agitated Restlessness Distressed |
Exhaustion Confused Altered level of consciousness |
| No accessory muscle use | Minimal accessory muscle use |
Moderate muscle use Nasal flaring Tracheal tug Hyperinflated chest |
Excessive muscle use Nasal flaring Tracheal tug Hyperinflated chest |
| Normal to a mild increase in respiratory rate | Tachypnoea |
Tachypnoea Dyspnoea Prolonged expiration |
Decreasing respiratory rate May only gasp occasionally |
| Normal pulse | Tachycardia | Tachycardia |
Decreasing heart rate Pulse may be hard to feel |
| Talks in sentences | Talks in phrases | Talks in 1 – 2-word gasps | Unable to talk |
| No central cyanosis | No central cyanosis | Cyanosis likely | Cyanosis |
| Variable wheeze | Moderate to loud wheeze | Often quiet wheeze | Often quiet wheeze (silent chest) |
| SpO2 more than 94% | SpO2 90 – 94% | SpO2 less than 90% | SpO2 less than 90% |
| Pulsus paradoxus not present | Pulsus paradoxus may be palpable | Pulsus paradoxus palpable | Pulsus paradoxus palpable |
Adapted from National Asthma Council Australia and Department of Health and Ageing, Australian Government6.
Wheeze is due to narrowing of intrathoracic airways and expiratory flow, irrespective of the underlying cause. Consider further investigation if assessment (history and examination) identifies any unusual features which suggest a non-viral cause.
| Respiratory |
|
| Other |
|
Investigations are not routinely recommended for a pre-school wheeze diagnosis2. They may be considered in a child with a severe or life-threatening exacerbation who is not responding to treatment, or an alternative diagnosis is being considered.
Venous blood gas (VBG) will allow monitoring of carbon dioxide, in addition to serum potassium, lactate and glucose as markers of potential Salbutamol toxicity. CXR may assist if considering an alternate diagnosis or to exclude complications of acute asthma such as collapse, pneumothorax or pneumomediastinum.
Viral PCR testing is not routinely recommended unless the result will alter management, for example some vulnerable children may require Influenza or Covid specific treatment.
Refer to the flowchart [PDF 656.48 KB] for a summary of the recommended emergency management and medications for a pre-school child with a wheezing illness:
Management is comprised of medications targeted at relieving acute bronchospasm, alleviating lower airway inflammation, and providing respiratory support in the form of oxygen and non-invasive ventilation. Corticosteroids may not be indicated in children with pre-school wheeze, especially those who present for the first time or with mild to moderate wheeze.
Frequent repeated clinical assessment is the best indicator to guide management.
Salbutamol (short acting inhaled beta2 agonist) is recommended for all pre-schoolers with wheeze7. Clinical review of the child post salbutamol is essential to determine treatment response. Wheeze alone, without increased work of beathing, is not necessarily an indication for salbutamol. The patient should be medically assessed no later than one hour after salbutamol administration to ensure the patient has responded to salbutamol. Providing hourly observation allows for review of the respiratory parameters (see table above) and if a further dose of salbutamol is needed. Parental concern or desaturation may prompt a review prior to this and salbutamol may be required prior to the 1 hour reassessment. Thus a patient may stretch with hourly increments after their initial dosing or they may be able to go straight to 3 hourly salbutamol.
Monitor oxygen saturations continuously if administering Salbutamol more often than every two hours. Bronchodilators may produce a paradoxical effect in children with underlying structural abnormalities such as bronchomalacia or tracheomalacia7.
| Metered dose inhaler (MDI) 100 micrograms (via spacer +/- mask*) | Age 1 to 5 years: 6 puffs |
| Nebulised | Age 1 to 5 years: 2.5 mg |
| Salbutamol burst | Administer three doses as above at twenty-minute intervals |
| Continuous nebulised Salbutamol | Use two 5 mg/1 mL nebules and replenish where reservoir empty. |
* Use mask also if unable to form a reliable seal on spacer
Cumulative Salbutamol doses can cause agitation, tremor, tachycardia, tachypnoea and rarely, hypertension. Raised lactate, hypokalaemia and raised glucose on VBG are markers of salbutamol toxicity.
Stretching the time between Salbutamol doses should be based on an assessment on the child. This should be done in collaboration with the child and caregiver30 and include:
A Cochrane review of the effect of adding an anticholinergic bronchodilator (Ipratroprium bromide) to salbutamol, shows reduced rate of hospital admission and improved side effect profile9. While there is no conclusive evidence for anticholinergics in children with mild exacerbations, it should be considered for children with moderate to severe symptoms in conjunction with Salbutamol MDI or combined with Salbutamol in nebuliser reservoir8.
| Metered dose inhaler (MDI) 20 micrograms* | Age 1-5 years: 4 puffs (84 micrograms) via spacer every twenty minutes for three doses |
| Nebulised | Age 1-5 years: 250 micrograms nebulised every twenty minutes for three doses |
Steroids are recommended for pre-school children with wheeze with:
Consider steroids for pre-school children with a history suggestive of an asthma phenotype e.g. atopy10.
While the evidence is still evolving, steroids are not currently recommended for initial therapy of pre-school children who present for the first time or infrequently with mild to moderate wheeze. A recent UK metanalysis concluded that Prednisone had a clear benefit at reduced length of hospital stay in children with viral associated wheeze11.
The traditional oral corticosteroid of choice is oral Prednisone/Prednisolone. However, dexamethasone has been shown to be non-inferior to prednisone and has the advantage of being a single dose, eliminating the need for steroids on discharge12,13.
| Dexamethasone (oral/IM/IV) |
Single dose on day 1 of 0.6mg/kg (maximum 16mg)12. The IV Dexamethasone preparation can be given orally, is tasteless and well tolerated in children. If IV stock is unavailable or in short supply, give oral liquid suspension noting the taste is unpleasant. Dexamethasone 0.5mg and 4mg tablets are available but they are not easily dispersed in water to give a partial dose. Doses that can be rounded to half or full tablet size can however be crushed and dispersed in water13. |
| Prednisolone (oral) |
Day 1: 2 mg/kg (maximum 50 mg) Day 2 and 3: 1 mg/kg (maximum 50mg) Can extend course to five days if still symptomatic after three-day course |
Seek senior emergency/paediatric input as per local practice for children requiring steroids IV. Consider seeking paediatric critical care input (onsite or via RSQ).
Consider in a child with severe or life-threatening wheeze who cannot tolerate oral medication or is not responding to inhaled bronchodilators and oral corticosteroids.
| Hydrocortisone (IV) | 4 mg/kg (maximum 100 mg) then every six hours on day one |
| OR Methylprednisolone (IV) | 1 mg/kg (maximum 60 mg) then every six hours on day one |
Seek senior emergency/paediatric input as per local practice for child requiring magnesium sulphate. Consider contacting paediatric critical care.
Consider in child with severe/life-threatening respiratory distress who is not responding to inhaled bronchodilators and corticosteroids.
Magnesium sulphate is thought to act by decreasing the uptake of calcium by bronchial smooth muscle cells, which leads to bronchodilation. In addition, it may have a role in inhibiting mast cell degranulation, which reduces inflammatory mediators14. There is no clear evidence to support use for the treatment of pre-school wheeze15.
Prescribe Magnesium in mmols and administer using safety software syringe drivers.
Administer Magnesium sulphate using safety software syringe drivers with a standard concentration of 0.5 mmol/ml. Each Magnesium sulphate 50% vial has a strength of 2 mmol/ml. Once the dose is drawn up, the dose should be diluted to a standard concentration of 0.5 mmol/ml e.g. a 10 kg child, the Magnesium sulphate dose is 0.2mmol/kg = 2 mmol. Draw up 1mL from the 2 mmol/ml vial and then dilute the dose to 4ml with a compatible fluid to give a standard concentration of 0.5 mmol/ml. Administer through a safety software syringe driver over 20 minutes.
| Bolus dose |
0.2 mmol/kg (equivalent to 50 mg/kg) given intravenously over 20 minutes (max 10 mmol/dose = equivalent to 2,500 mg) Doses up to 0.4 mmol/kg (maximum of 10 mmol) have been used. Must be administered in syringe driver using safety software. |
| Side effects | Usually minor, including epigastric or facial warmth and flushing, pain and/or numbness at infusion site and dry mouth. Severe reactions include allergy, hypotension, respiratory depression and circulatory collapse. |
| Monitoring |
Full cardiac monitoring with blood pressure every five minutes. Cease infusion if hypotension persists. Monitor knee reflexes if repeating dose to assess for magnesium toxicity which can result in respiratory failure. Cease magnesium if reflexes absent. |
Contact paediatric critical care specialists (onsite or via RSQ) for children requiring Salbutamol IV.
Salbutamol IV is only recommended for children with a very severe acute wheeze.16
Administer an initial bolus dose and monitor closely for signs of Salbutamol toxicity. Slow or cease infusion if significant concerns. Evaluate the clinical response to this initial dose and consider progression to a Salbutamol IV infusion.
| Bolus dose | 15 microgram/kg (maximum 300 micrograms) infused over twenty minutes |
| Infusion | 0.5-1 microgram/kg/min (maximum 40 micrograms per min). Higher doses may be required under the direction of the PMC or Intensivist. |
| Side effects | Cumulative doses of Salbutamol can cause agitation, tremor, tachycardia, tachypnoea and rarely, hypertension. Raised lactate, hypokalaemia and raised glucose on VBG are markers of Salbutamol toxicity. |
| Monitoring |
Full cardiac monitoring Monitor venous potassium levels. |
Contact paediatric critical care specialists (onsite or via RSQ) prior to administering Aminophylline IV.
Traditionally, Aminophylline IV has been used in children with severe wheeze who are unresponsive to maximum doses of bronchodilators and steroids in the critical care setting. Aminophylline improves lung function within six hours of treatment, however there is limited improvement in symptoms, and no reduction in duration of hospital admission17. It is also associated with numerous side effects including vomiting4. Aminophylline should not be given as an intravenous infusion in the patient already taking oral Theophylline. Please see CREDD for dosing.
Contact paediatric critical care specialists (onsite or via RSQ) for children requiring Adrenaline IM
In life threatening bronchospasm, consider anaphylaxis
Consideration should be given for the role of intramuscular adrenaline, especially if there is a known history of anaphylaxis or new allergen exposure. Severe bronchoconstriction will limit Salbutamol efficacy via the inhalation route.
| < 10 kg | 100 microg (0.1mL of 1:1000) |
| 10-12 kg | 100 micrograms (0.1mL of 1:1000) |
| 13-15 kg | 150 micrograms (0.15mL of 1:1000) |
| 16-21 kg | 200 micrograms (0.2mL of 1:1000) |
| 22-34 kg | 300 micrograms (0.3mL of 1:1000) |
| 35-49 kg | 400 micrograms (0.4mL of 1:1000) |
| More than 50kg | 500 micrograms (0.5mL of 1:1000) |
Oxygen should be initiated for children who are hypoxic (saturations < 90%) once initial therapy has been delivered18. It is not uncommon for children to desaturate related to an initial V/Q mismatch during initiation of therapy or while asleep due to reduced respiratory effort. It is important to promptly review children who are desaturating to formulate an opinion of cause and therefore management. If considered due to respiratory failure, adjunct respiratory therapy should be considered such as HFNC.
Seek urgent paediatric critical care advice (onsite or via RSQ) if commencing HFNC therapy or NIV.
While early use of HFNC has not been shown to reduce length of hospital stay compared to standard oxygen therapy in infants with bronchiolitis19, HFNC therapy and NIV can be considered in patients with acute respiratory insufficiency who have not responded to standard therapies.
Consider HFNC therapy, CPAP or BiPAP for a child who:
Nebulised salbutamol can be delivered through specific HFNC circuits (900PT562) although delivery through the circuit may be inferior. Follow local policies and procedures for delivery and ongoing management of HFNC20. View View CHQ Nasal High Flow Therapy Guideline and Management of Severe Acute and Life-threatening Asthma in PICU.
Contact paediatric critical care specialists (onsite or via RSQ) if considering intubation and ventilation.
The following medications are not routinely recommended in the acute management of pre-school wheeze8:
Patients presenting to Emergency with recurrent flares of pre-school wheeze may benefit from a 3 month trial of a preventer if they have had several acute episodes in the previous 12 months. Consider introducing a preventer inhaler, such as Fluticasone, if any of the following criteria are met21.
Follow up should occur with the GP to determine efficacy of the trial at the end of 3 months.
| Medication | Management |
|---|---|
| Inhaled corticosteroids |
Dose (1-15 years of age): fluticasone propionate 50microg twice daily A RCT of long-term inhaled corticosteroid demonstrated improvement (smaller effect than school-aged-children and adults) in symptoms, exacerbation rates, lung function, and airway hyper-responsiveness22,23 |
On discharge a child should be provided with:
Follow-up
Clinicians can contact the services below if escalation of care outside of senior clinicians within the ED is needed, as per local practices. Transfer is recommended if the child requires a higher level of care.
| Includes children with the following (as a guide) | |
|---|---|
| |
| 1-4 years | 5-11 years |
|
|
| Reason for contact | Who to contact |
|---|---|
| For immediate onsite assistance including airway management | The most senior resources available onsite at the time as per local practices. Options may include:
|
| Paediatric critical care advice and assistance | Onsite or via Retrieval Services Queensland (RSQ). If no onsite paediatric critical care service contact RSQ on 1300 799 127:
RSQ (access via QH intranet) Notify early of child potentially requiring transfer. Consider early involvement of local paediatric/critical care service. In the event of retrieval, inform your local paediatric service. |
| May include children with |
|---|
|
| Reason for contact | Who to contact |
|---|---|
| Advice (including management, disposition or follow-up) |
Follow local practices. Options:
|
| Referral | First point of call is the onsite/local specialist or paediatric service |
| Do I need a critical transfer? |
|
| Request a non-critical inter-hospital transfer |
|
| Non-critical transfer forms |
|
Consider discharge for children who meet ALL of the following:
Consider a longer period observation in STTA or inpatient service for the despite looking well for a child with a history of sudden deterioration or admission to critical care despite looking well.
An assessment of the family’s ability to safely manage the child at home should be done as per the Pre-school Wheeze Disease Education Checklist [DOCM] (QH staff only) prior to discharge.
On discharge a child should be provided with:
Consider admission for child with:
Despite meeting the clinical discharge criteria admission may be considered for the following patients:
Considering admission to a STTA if:
Children who require bronchodilator therapy more frequently than one hourly require vigilant monitoring and regular review by medical staff. Unless specifically discussed with STTA medical and nursing staff, the child should remain in the acute assessment area of the ED.
During admission to STTA:
There is little evidence to support specific requirements and local practices will dictate criteria for admission from STTA to an inpatient ward. Consider admission for the following: