A report from the front line

Dr Kathryn Ryan, Chair of the Clinical Biochemistry Specialty Advisory Committee, and consultant clinical biochemist at Belfast Health and Social Care Trust explains how clinical biochemistry is vital in monitoring patients with COVID-19, and reflects on her time working in critical care during the pandemic.

In March 2020, in a speech referring to the escalating number of cases of COVID-19, the head of the World Health Organization said, ‘Our key message is: test, test, test.’ And this pandemic has highlighted the indispensable role of healthcare laboratories in identification and management of patients infected with SARS-CoV-2. The focus has justifiably been on our colleagues in virology who rapidly implemented testing for SARS-CoV-2 and then, at pace, expanded the volume of tests available. However, all laboratory disciplines have discovered their specific role in the pandemic. Laboratory tests are performed for four main purposes: diagnosis, screening, monitoring and research. My own specialty is clinical biochemistry. Our laboratories analyse the chemicals present in blood, urine and other body fluids in order to diagnose disease, screen for pre-symptomatic conditions, assess prognosis and monitor treatment. In patients with COVID-19, clinical biochemistry tests are largely performed to assess prognosis and monitor the course of the disease in patients.

In Belfast, patients with COVID-19 who did not require critical care were admitted to the Mater Infirmorum Hospital. Patients who needed intensive support were cared for in Belfast City Hospital, which was repurposed as the Northern Ireland Nightingale Hospital. Biochemistry tests, along with clinical assessment, guided the admission of patients and escalation of their care. We measured blood oxygen and carbon dioxide to provide an initial measure of disease severity.

In March, when hospitals in Lombardy, France, and Madrid, Spain, were struggling to manage the number of acute admissions, lead clinicians in our trust developed a strategy to increase acute medical and critical care capacity.

During hospital admission, we monitored kidney function and electrolytes, such as sodium and potassium, to guide fluid replacement and indicate if haemodialysis, to purify the blood, was required in the most ill patients. However, the key role of biochemistry in COVID-19 was the measurement of inflammatory markers. These measurements assisted in establishing prognosis, stratifying risk and therefore guiding resource allocation. As more evidence is gathered from studies of patients with COVID-19, it may be possible to use a combination of clinical features and biochemical tests to determine more accurately who needs hospital admission, identify deteriorating patients who need intensive support and guide the use of specific therapies. My colleagues and I therefore had a role in advising which biochemistry tests would be useful, how frequently they should be measured and how results are interpreted.

In March, when hospitals in Lombardy, France, and Madrid, Spain, were struggling to manage the number of acute admissions, lead clinicians in our trust developed a strategy to increase acute medical and critical care capacity. This included not only equipment but personnel. There had been a rapid downturn in elective care to reduce footfall in the hospital and potentially reduce transmission of COVID-19. My outpatient clinics in diabetes, lipids and inherited metabolic disease were paused.

There was a great sense of camaraderie: we watched the sun rise from our base in level 2 and there were many interesting coffee room conversations.

With routine work largely on hold, the chemical pathology team in our trust participated in training so that we could be allocated to critical care in the Nightingale Hospital. We were assigned to ‘pods’, or teams of six doctors, from a variety of specialties and grades. These pods were led by a consultant intensivist. Despite all the potential stress of working outside my specialty, in a new team and in the middle of lockdown, this was an immensely rewarding experience. There was a great sense of camaraderie: we watched the sun rise from our base in level 2 and there were many interesting coffee room conversations.

We were resident for 12-hour shifts, going into the unit in pairs using full personal protective equipment (PPE) for two hours at a time. There was a high level of responsibility to protect colleagues from infection and each person checked that their partner put on and removed PPE correctly. We paired up to maximise our skills and expertise, so an airway specialist would work with a doctor from another specialty. I enjoyed revising and then applying respiratory physiology; training how and when to change settings on a ventilator; learning how to prone (turn a patient onto their stomach); and also using some of my established skills in diabetes care and blood gas interpretation.

I am now appreciating a return to my usual role and reconnecting with my clinic patients and laboratory colleagues. While I could not have anticipated my short sabbatical in critical care medicine, it was a privilege to work with colleagues from many specialties and understand a little more of how the laboratory can support our patients and colleagues in the specific challenges they face.