Asthma

Developed in collaboration with CASA Medical.

Asthma is a long-term lung disease affecting people of all ages. It is caused by inflammation and muscle tightness around the airways, which make it harder to breath. Symptoms can include coughing, wheezing, shortness of breath and chest tightness. These symptoms can be mild or severe and can come and go over time. It can be controlled but not cured.

In clinical practice, asthma is defined by the presence of both the following:

• excessive variation in lung function (‘variable airflow limitation’, i.e. variation in expiratory airflow that is greater than that seen in healthy people)
• respiratory symptoms (e.g. wheeze, shortness of breath, cough, chest tightness) that vary over time and may be present or absent at any point in time. 

Asthma is often under diagnosed and under treated. Untreated asthma is usually characterised by chronic inflammation involving many cells and cellular elements, airway hyperresponsiveness, and intermittent airway narrowing (due to bronchoconstriction, congestion or oedema of bronchial mucosa, mucus, or a combination of these).

Asthma, a severe and chronic condition, impacts 1 out of 9 Australians and New Zealanders. While there is presently no cure, effective management strategies enable most individuals with asthma to lead fulfilling lives. Asthma entails having sensitive airways, prone to inflammation or swelling upon exposure to certain triggers. Trigger-induced changes in the airways include thickening of airway walls, accumulation of mucus, and constriction due to muscle tightening around the airways, collectively impeding normal breathing. A diagnosis of asthma is typically made by a doctor through a comprehensive assessment of medical history, symptoms, and possibly lung function tests like spirometry. Asthma can be diagnosed at any stage of life, underscoring the importance of ongoing monitoring and management.

Asthma should be managed as outlined in the Australian Asthma Handbook or NZ Guidelines. Reliever medication (bronchodilator such as salbutamol) must always be readily accessible while flying or operating.

Pilot and controller information

Stop flying or operating and report to ME or CAA NZ for any of the following:

• With asthma symptoms
• An asthma attack requiring emergency treatment, hospitalisation or significant symptoms not responding to your inhaler medication
• Use of regular oral corticosteroid medication > 10mg/day
• You are advised by a health professional that you are not fit to fly or operate

Aeromedical implications

Effect of aviation on the condition

• Mild hypoxia with altitude
• Gas trapping
• Stress and workload related to flying or operating
• Cold dry air at altitude may provoke symptoms
• Smoke and fumes may provoke symptoms

Effect of the condition on aviation

• Acute incapacitation from severe bronchoconstriction/asthma attack.  
• Worsening hypoxia leading to cognitive impairment.
• Severe dyspnoea impairs speech and communication.

Approach to medical certification

Important factors in aeromedical decision making are:

Based on the condition

Factors that are considered in the stability of asthma eg:

• Absence of current or recent history of asthma symptoms
• Increase in FEV1 (change of 12% from baseline for adults and ≥ 200ml) 10–15 minutes after administration of bronchodilator.
• Variation in lung function (at least 20% change in FEV1) when measured repeatedly over time (e.g. spirometry on separate visits).
• Variation in serial peak expiratory flow (diurnal variability of more than 10%) - if done. 

Based on treatment

• Longer term oral steroid treatment > 10mg per day (or equivalent) or monoclonal antibody treatment for prevention will be assessed case by case.
• Demonstrated compliance with their treatment plan

Demonstrated stability

• Asymptomatic and no limitations on activities
• No hospitalisations/emergency department treatment in last 12 months
• No requirement for oral or intravenous steroids
• Short-acting beta agonist use >1 canister/month

Risk assessment protocol - information required

New cases

Risk assessment is based on history, active symptoms, response to medical management, precipitants, and frequency of asthma attacks.   Consideration should be given to history of hospital admissions, use of oral corticosteroids, and regular high doses of inhaled corticosteroids.  Spirometry pre and post bronchodilator is helpful in the assessment of reversible bronchoconstriction.

A previous diagnosis of asthma, if mild, well managed and asymptomatic, is not necessarily a bar to certification.  Asthma that is well managed with inhaled corticosteroids can be safe in the aviation environment with few occurrences in flight.

A history of childhood asthma which has never recurred is typically not a concern for certification.

Please complete the CAA Respiratory examination report (24067-213) [DOCX 39 KB]

• Confirmed diagnosis
  • Report from treating doctor or respiratory specialist
• Clinical status
  • Progress
  • Reliever use – what and how often
  • Preventative therapy – low to moderate doses of ICS only
  • Exacerbations (precipitating factors / frequency / severity / steroid use / hospitalisations).
• Investigations conducted
  • Spirometry results pre and post bronchodilator (mandatory within past 3 months)
  • Bronchial challenge test (if undertaken)
  • Other tests and interventions previously undertaken
• Management
  • Treatment
  • Side-effects
  • Monitoring /peak flow diary
  • Asthma management plan
  • Follow-up plan
  • Previous specialist reports if available.

Renewal

Treating Doctor’s Report, specialist report and CAA Respiratory examination report (24067-213) [DOCX 39 KB]

• Clinical status
  • Progress
  • Reliever use – what and how often
  • Preventative therapy – low to moderate doses of ICS only
  • Exacerbations (precipitating factors / frequency / severity / steroid use / hospitalisations).
• Investigations conducted since last review
  • Spirometry results pre and post bronchodilator (mandatory within past 3 months)
  • Bronchial challenge test (if undertaken)
  • Other tests and interventions previously undertaken
• Management
• Treatment
• Side-effects
• Monitoring /peak flow diary
• Asthma management plan
• Follow-up plan

ME aeromedical decision guide

If ALL the criteria in the table below the ME may proceed with medical certification. Evidence supporting the ME’s decision (for example reports and results) must be sent to CAA AvMed.

ME must confirm	Tick
Treating specialist/GP finds condition is stable on current management and no changes recommended
Symptoms: Stable and well-controlled (either on or off medication) Yes for all the following Asymptomatic and no limitations on activities Use of oral steroids for exacerbations – no more than 2 times annually In the last year No in-patient hospitalisations No more than 2 outpatient/ GP/urgent care visits for exacerbations (with symptoms fully resolved)
ACCEPTABLE medications One or more of the following Level 1 –3 treatment as per Australian Asthma Handbook/ NZ guidelines Leukotriene receptor agonist eg montelukast Pilots/controllers with acute exacerbations – a short 10-day course of up to 50mg daily oral steroids (prednisone) may be cleared by ME when well. MEs must advise pilots/controllers not to fly or operate until the course of steroids is completed, and the individual is symptom free. NOT ACCEPTABLE Regular prednisone > 10mg daily Biologics and non-biologics – eg Monoclonal antibodies
Lung function tests Current within the last 3 months FEV1, FVC greater than 80% predicted FEV1/FVC ratio are to or greater than 75%
ME considers safe to certify

An AMC referral to CAA NZ Aviation Medicine teams is required if a pilot’s or controller’s condition does not meet all the above criteria and they consent to their condition being considered under flexibility to the CAR 67 rules.

Recommended conditions of medical certificate:

• Required to carry a bronchodilator inhaler when flying or controlling

ME letters

Asthma medical certificate letter [DOCX 21 KB]

Asthma 020 operational restrictions letter [DOCX 28 KB]