Speaker's Highlight

• Don Sin University of British Columbia, St. Paul Hospital (Canada)
  Kenneth R. Chapman Toronto General Hospital Research Institute (Canada)
• Parameswaran Nair McMaster University (Canada)
  Carolyn Calfee UCSF (U.S.A.)
• Gregory P. Downey University of Colorado School of Medicine (U.S.A.)
  David A. Schwartz University of Colorado School of Medicine (U.S.A.)
• Neil Schluger Tuberculosis Control Branch, California Department of Public Health (U.S.A.)
  Nick Kim Critical Care & Sleep Medicine, University of California San Diego (U.S.A.)
• Nicola Hananiah Baylor College of Medicine (U.S.A.)
  Jae-Joon Yim Seoul National University College of Medicine (Republic of Korea)
• Koichiro Asano Tokai University School of Medicine (Japan)
  Diahn-Warng Perng Taipei Veterans General Hospital (Taiwan)
• Konstantinos Kostikas University of Ioannina (Greece)
  Karin Klooster University Medical Center Groningen (Kingdom of the Netherlands)

• Managing Acute Asthma Exacerbations in the Intensive Care Unit

  Severe asthma can deteriorate rapidly from respiratory distress to exhaustion, dynamic hyperinflation and cardiovascular collapse. In the intensive care unit, treatment depends on recognising worsening airflow obstruction early, delivering bronchodilator therapy without delay and avoiding interventions that increase air trapping. The patient’s response over minutes and hours is often more informative than a single spirometry result, especially when fatigue or altered consciousness prevents reliable testing.

  Australian clinicians must also consider the circumstances surrounding an exacerbation. Melbourne’s seasonal thunderstorm asthma events, Sydney bushfire smoke, occupational exposures and limited access to regular preventer therapy in some rural communities can all influence presentation. A careful history should cover recent viral symptoms, allergen exposure, medication access, inhaler technique, previous ICU admissions and the patient’s written asthma action plan.

  Recognising Life-Threatening Airflow Obstruction

  Initial assessment follows an airway, breathing and circulation approach while treatment begins. Inability to speak in sentences, exhaustion, silent chest, cyanosis, confusion, poor respiratory effort, severe accessory muscle use and deteriorating oxygenation indicate a high-risk episode. Peak expiratory flow can help when feasible, but a critically unwell patient should not be delayed for a technically difficult measurement.

  Blood gas analysis is useful when there is severe distress, altered mental state or concern about ventilatory failure. A low or normal arterial carbon dioxide level may occur early because the patient is hyperventilating. A rising PaCO₂, worsening acidosis or falling respiratory rate suggests fatigue and inadequate alveolar ventilation. Chest imaging is not routine for every exacerbation, but it is appropriate when pneumothorax, pneumonia, pulmonary oedema or another diagnosis is suspected.

  First-Hour Treatment And Monitoring

  Give repeated or continuous inhaled salbutamol, usually through a nebuliser or metered-dose inhaler with a large-volume spacer, according to local ICU protocol. Add nebulised ipratropium in severe attacks. Oxygen should be titrated to correct hypoxaemia, commonly targeting an SpO₂ of about 92–96% in adults unless another condition requires a different range. Continuous cardiac monitoring is appropriate because beta-agonists may cause tachycardia, hypokalaemia and lactic acidosis.

  Systemic corticosteroids should be administered early, using intravenous hydrocortisone or methylprednisolone when oral treatment is not practical. Intravenous magnesium sulfate is a reasonable adjunct for severe bronchospasm that responds inadequately to initial therapy. Antibiotics should be reserved for a documented or strongly suspected bacterial infection; purulent sputum alone does not establish that diagnosis. Intravenous aminophylline and routine intravenous beta-agonist infusions generally have limited roles because toxicity can outweigh benefit.

  Frequent reassessment should include respiratory effort, speech, mental state, respiratory rate, heart rate, oxygen requirement, air entry and blood gas trends. A fall in wheeze is not necessarily improvement: a quieter chest in a tiring patient may reflect critically reduced airflow. Fluid management should be cautious, particularly when tachycardia, right-heart strain or the effects of positive pressure ventilation are present.

  Ventilatory Support And Intubation

  Non-invasive ventilation may help a carefully selected, cooperative patient with persistent work of breathing, but it must never delay intubation. It is unsuitable when there is deteriorating consciousness, vomiting, severe agitation, inability to protect the airway, haemodynamic instability or rapidly worsening gas exchange. Close observation by an experienced ICU team is essential because positive pressure can worsen hyperinflation.

  Intubation is technically and physiologically hazardous. It should be considered for refractory hypoxaemia, progressive hypercapnia with acidosis, exhaustion, reduced consciousness, cardiac arrest or inability to maintain ventilation. Preparation should include senior airway support, vasopressor readiness and a plan for difficult haemodynamics. Ketamine may be useful for induction because of its bronchodilatory properties, although the choice should reflect patient factors and local practice.

  After intubation, ventilation should prioritise avoidance of dynamic hyperinflation rather than normalising carbon dioxide quickly. Use a low respiratory rate, modest tidal volume, high inspiratory flow and a prolonged expiratory time. Permissive hypercapnia may be accepted if pH remains clinically tolerable. Monitor for auto-PEEP, rising plateau pressure, hypotension and abrupt cardiovascular collapse. If severe hypotension occurs, disconnecting the ventilator briefly to allow trapped gas to escape may be lifesaving while other causes are assessed.

  Australian Factors In Emergency Care

  Environmental triggers matter in Australia. Smoke from major bushfires can worsen asthma across metropolitan and regional areas, while pollen-related thunderstorm asthma is particularly relevant in Victoria. Patients should be asked about outdoor exercise, workplace dust, mould, pets, vaping and exposure to smoke or air pollution. State and territory smoke-free legislation supports prevention, but household exposure and informal outdoor smoking can still affect vulnerable people.

  Access and prescribing patterns also shape outcomes. In remote Queensland, Western Australia and the Northern Territory, transport times and limited after-hours services may mean patients arrive later and sicker. In metropolitan centres such as Melbourne, Sydney and Brisbane, emergency departments may face surges during viral seasons or severe air-quality events. The Pharmaceutical Benefits Scheme, community pharmacies and availability of spacers influence whether patients can maintain inhaled corticosteroid treatment after discharge.

  Australian practice should align with current National Asthma Council Australia guidance, hospital protocols and medicines approved by the Therapeutic Goods Administration. Any off-label therapy, medication substitution or high-risk infusion should be governed by local policy, appropriate prescribing authority and clear documentation. Discharge planning must account for the patient’s ability to obtain medicines, understand written instructions and access follow-up care through a general practitioner or respiratory service.

  Practical Recommendations For ICU Teams

  A reliable care pathway can reduce variation during a rapidly evolving attack. Team members should identify the patient’s baseline severity, previous intubation history, usual preventer, recent reliever use and likely trigger while treatment is underway. Communication with paramedics, emergency clinicians, family and the receiving ward helps preserve details that may be lost during sedation or transfer.

  Before discharge from intensive care, the immediate crisis should be linked to long-term prevention. Check inhaler technique with the actual device, prescribe an appropriate anti-inflammatory preventer, update the written action plan and arrange follow-up. Where relevant, involve a pharmacist, asthma educator or Aboriginal and Torres Strait Islander health service to address practical barriers and culturally safe care.

  • Start inhaled bronchodilators and systemic corticosteroids promptly, with objective reassessment after each treatment phase.
  • Watch for fatigue, rising carbon dioxide, silent chest and worsening acidosis rather than relying on wheeze alone.
  • Use non-invasive ventilation selectively and prepare early for controlled intubation when deterioration continues.
  • Set the ventilator to allow prolonged expiration and actively monitor for auto-PEEP and dynamic hyperinflation.
  • Before discharge, address preventer access, spacer use, trigger reduction and follow-up through local Australian services.

  The safest approach combines rapid pharmacological treatment with disciplined reassessment and a ventilation strategy that respects the mechanics of severe airflow obstruction. In practice, early recognition, careful preparation for intubation and a clear prevention plan are the measures most likely to turn a dangerous ICU admission into a controlled recovery.

  Richard Russell Nuffield Department of Clinical Medicine, University of Oxford (United Kingdom)
• Mona Bafadhel King’s College London (United Kingdom)
  David Jackson Guy’s and St Thomas’ Hospital, King’s College London (United Kingdom)
• James Chalmers University of Dundee (United Kingdom)
  David Price University of Aberdeen (United Kingdom)