The NHS is at the forefront of the UK’s response to the covid-19 outbreak. Hospitals are already being overwhelmed with cases of suspected and confirmed covid-19 infection, with clinicians struggling to keep up with the variety of presentations and symptoms—from non-specific coryzal symptoms, fever and breathlessness, through to vague abdominal pain. This is made more challenging by the fact that coronavirus PCR testing is still taking up to 24 hours or more. 

We are in unprecedented territory. UK radiology departments are moving to “clean” and “covid” CT scanners, and the system is almost at breaking point even before the peak is upon us. NHS trusts have already been told to suspend all non-urgent elective surgery for three months. Those NHS Trusts that have been hit the worst are already cancelling elective imaging to create extra capacity. In contrast, many of those NHS trusts yet to experience the upsurge in cases of covid-19 are still scanning routine outpatients because there has not yet been a central direction to the contrary.

Radiologists now find themselves at the frontline of helping to manage the covid-19 outbreak. The chest x-ray (CXR) has emerged as the frontline diagnostic imaging test, in conjunction with clinical history and key blood markers: CRP and lymphopaenia. With PCR turnaround times lagging at 24-48 hours, these basic blood biomarkers have become the bedrock of covid-19 patient triage.

So, what have we learnt from our experience so far of providing radiology services during the covid-19 outbreak? 

Every suspected covid-19 patient presenting to the accident and emergency department is undergoing blood tests and a chest x-ray. Therefore, it has become critical for radiologists to review and “hot” report the chest x-ray urgently. While the lack of UK radiology capacity is a huge barrier to this, departmental resources have been redirected to prioritise chest x-ray reporting over any other imaging investigation. This is allowing more rapid determination of patients without covid-19 lung infection from probable cases of covid-19, especially when simple template reporting systems are employed to facilitate both faster reporting and report tracking.  

With at least 20% of the NHS workforce expected to be self-isolating at some stage during the pandemic, radiology departments must recognise the critical need to protect the radiographer workforce with appropriate personal protective equipment. Having multiple radiographers self-isolating for 2-week periods could well lead to a more widespread outbreak of covid-19 infection through the UK due to an inability to efficiently perform chest x-rays on unwell patients. With frontline clinicians now relying on rapidly reviewed chest x-rays to appropriately triage the sickest patients (whilst awaiting diagnostic PCR tests), this would add even more burden to an overstretched system.

With the most severely unwell covid-19 patients increasingly undergoing CT scanning for potential risk stratification, it has become necessary to review their CT scans while the patients are still on the CT scanning table. This also applies to patients undergoing CT chest scans for other conditions, as well as scans performed for abdominal pain, where the bottom of the lungs may be captured on the study. The reason for this extends beyond rapid clinical diagnosis. Such is the fear around contaminating non-infected patients with covid-19, this “hot CT scan” review has become necessary to assess whether the CT scanning equipment is likely to need a prolonged deep clean (in patients with features suspicious of covid-19 infection), or a shorter wipe-down. 

Inevitably we are already seeing several cases where patients who are not initially suspected of having covid-19 infection are being sent for CT scanning without appropriate sterile precautions, only for the scan to unexpectedly demonstrate coronavirus infection. This is emerging as a real issue in the attempt to keep the scanning environment clean and radiographers safe from infection. If at all possible, CT scan requests in more stable patients with fever or lymphopaenia are being temporarily put on hold until a confirmed covid-19 PCR result arrives. This is so radiologists can decide if the CT scan should take place on the “covid CT scanner” or the nominated “clean” CT scanner, thereby reducing the potential risk of contamination and further spread of infection.

This has been a steep learning curve for frontline clinicians. Such is the novel nature of this disease, decision making by clinical radiologists is emerging as one of the key parts of frontline triage. This is perhaps best demonstrated in patients presenting with abdominal pain and no respiratory symptoms to initially suggest covid-19 pulmonary infection. We all have a duty to share our experiences with colleagues, and learn from those ahead of us on the curve.

Samanjit S Hare, Consultant Chest Radiologist, Royal Free London NHS Foundation Trust. Twitter @lungdiagnosis

Jonathan Rodrigues, Consultant Chest Radiologist, Royal United Bath Hospitals Bath NHS Foundation Trust. Twitter @JCLRodrigues

Arjun Nair, Consultant Chest Radiologist, University College London Hospital. Twitter @lungradiologist

Graham Robinson, Consultant Chest Radiologist, Royal United Bath Hospitals Bath NHS Foundation Trust. Twitter @DrGRERobinson

All four authors are committee members of the British Society of Thoracic Imaging. Twitter: @BSTIImaging

Competing interests: None declared.

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