The COVID-19 pandemic has made comprehensive evaluation to enable an accurate diagnosis to be reached while minimising the risk for cross-infection more challenging. This new position statement offers pragmatic advice on diagnosis based on history, physical examination and presenting symptoms.
The recommendations from PCRS recognise that certain procedures with the potential for droplet or aerosol formation such as spirometry may not currently be possible or appropriate.
PCRS recommends that for patients in whom a diagnosis of asthma is suspected, a trial of treatment with peak flow monitoring is already the recommended approach.
For those with suspected COPD, peak expiratory flow rate (PEFR) can be informative although it is necessary to ensure the patient is well trained to undertake PEFR independently. Training can take place via video consultation.
Confirmatory spirometry can be deferred for when it is considered safe and is readily available. Diagnostic spirometry should be reserved for those in whom the diagnosis is equivocal and is necessary to determine the appropriate treatment course. When testing procedures with the potential for cross-infection are considered necessary, the patient should ideally be referred to a networked respiratory diagnostic service.
The recommendations bring together the cross-functional experience of PCRS members on the safest and most appropriate approach when evaluating patients presenting with respiratory symptoms. Dr Noel Baxter, GP and PCRS Policy Forum Chair said: ‘Many practitioners may have concerns about how they can effectively diagnose patients presenting with respiratory symptoms during COVID-19. But it is essential that patients presenting with respiratory symptoms continue to be properly assessed by a healthcare professional.’
Carol Stonham, PCRS Executive Chair, added: ‘This guidance helps to restate best practice and offers some clarity for practitioners, especially nurses who conduct diagnostic tests including spirometry, as they continue to adapt to the changes and challenging conditions caused by COVID-19.’
DIAGNOSTIC TESTS IN ASTHMA
PEFR diary measurements can be carried out safely at home. If PEFR evaluation in clinic is considered necessary this can be carried out using the patient’s own PEF meter and disposable mouthpiece in a room with an open window or outside the building.
Only patients with an intermediate probability of asthma should be considered for further investigations.
Spirometry will show airways obstruction less than half the time even when the person is subsequently diagnosed with asthma. It is frequently normal in patients with asthma unless they are experiencing a current worsening of symptoms. The potential for droplet formation and therefore viral transmission means that spirometry should be used for asthma diagnosis at present.
FeNO is still not widely available in the majority of primary health care settings, and while useful, cannot be considered essential at this time. QALYs calculated in NICE asthma guidance are no longer applicable because they were based on reusable devices and single use cartridges. As it is not safe to use the device between patients, the device cost prohibits single patient use.
DIAGNOSTIC TESTS IN COPD
The diagnosis of COPD can only be made if fixed airflow obstruction without reversibility is demonstrated, unless there is evidence of emphysema on a CT scan.
In the absence of spirometry, PEFR <75% predicted demonstrates a degree of airflow obstruction.
Serial measurement over 2 weeks that does not vary but remains low despite use of salbutamol for symptom relief would suggest fixed airflow obstruction and is suspicious for COPD in the context of supporting clinical history.
Patients who do not have variation in peak flow should have an empirical trial of dual bronchodilator therapy.
Any provisional diagnosis of COPD should be confirmed with spirometry when it becomes available again. Record in the patient’s notes that spirometric confirmation of obstruction without reversibility is required at a later date.
PCRS. Diagnostic work up of the patient presenting with respiratory symptoms during the COVID-19 pandemic; 24 June 2020. https://www.pcrs-uk.org/resource/diagnostic-work-patient-presenting-respiratory-symptoms-during-covid-19-pandemic