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LONG COVID: What to do when you spot the signs

LONG COVID: What to do when you spot the signs
Sick woman lying in bed

Long covid is defined by NICE1 as ‘signs and symptoms that continue or develop after acute Covid-19…[including]… both ongoing symptomatic Covid-19 (from four to 12 weeks) and post-Covid-19 syndrome (12 weeks or more)’. Around 10% of those who have tested positive for Covid-19 are symptomatic for 12 weeks or more and the range of possible symptoms is wide (see below). This article will cover the initial assessment of a patient with possible long Covid.

  • Cardiac/respiratory – shortness of breath, reduced exercise tolerance, chest pain, palpitations and cough
  • Neurological – dizziness, memory loss, difficulty in concentrating, headache, sensory symptoms (pins and needles/numbness), delirium (more common in older patients)
  • General – fatigue, insomnia, ongoing fever
  • Psychiatric – anxiety, depression, symptoms of post-traumatic stress disorder
  • Gastrointestinal – diarrhoea, nausea, abdominal pain, reduced appetite and weight
  • Skin – rashes and chilblains on the toes (so-called ‘covid toes’)
  • Metabolic – worsening of diabetes control
  • Musculoskeletal – joint and muscle pain and weakness
  • ENT – tinnitus, sore throat, ear pain, prolonged loss of taste and smell

The first thing to do is to exclude red flags which might indicate severe disease needing acute referral to hospital. You might consider stroke, pulmonary embolism, acute coronary syndrome and acute arrhythmia, which could present with sudden onset weakness, new chest pain, shortness of breath, palpitations, drowsiness or syncope on exertion. Oxygen saturations below 94% should always make you consider admission. Whilst we are all keen to avoid sending patients to hospital at the moment, make sure that you don’t adjust your referral threshold too high – sick patients still need acute assessment in secondary care.

Remember that not every patient with long Covid will have had a positive Covid test, or positive antibodies.1 For much of 2020, only those who were admitted got tested;3 patients treated at home were presumed positive on the basis of symptoms. We also know that positive antibody tests reduce over time,4 so negative antibody tests can’t exclude long covid.

It is also true that not everybody who is unwell after having Covid will have long Covid; remember your core clinical skills of history taking and be open to other diagnoses. An open mind, and an open style of history taking is important at the first appointment and every subsequent time that the patient is seen. Allow the patient to speak for as long as they need to, without interruption, and note down all the symptoms that concern them. This will be useful for future appointments, even if you can’t deal with everything today. After that, use a more closed consultation style to exclude acute severe conditions, and to ask about any specific symptoms that you think are important. Negative answers can be just as important as positive ones and should also be documented in the notes.

An initial examination might include pulse, blood pressure, temperature and oxygen saturations. If your patient is describing fatigue and shortness of breath then it is useful to know if this is associated with desaturation. The Covid oximetry @home scheme5 lends pulse oximeters to patients with Covid, to see if they are desaturating. You may have something similar in your area for patients with symptoms of long Covid, or your patient may have already bought a meter, as many did during the pandemic. Ask the patient to do the things that make them fatigued/short of breath whilst wearing a pulse oximeter and to record the results. A drop to below 94% is concerning, although for some patients with chronic lung disease their normal may be below 94%, in which case you should interpret the readings with their baseline values in mind.

You can also test for exertional desaturation in your clinic; these tests have not been specifically validated for long Covid, but are used for other lung conditions. Examples include the one minute sit to stand test (the patient goes from sitting to standing as many times as they can in one minute) and the 40-step test (the patient takes 40 steps on a flat surface).6 As long as the patient has normal resting saturations, these tests are unlikely to cause harm, but they should be stopped if there is significant shortness of breath and once desaturation has been proven (even if the test is not finished).

One prominent feature of long Covid is postural tachycardia syndrome (PoTS). This was known as a clinical entity before Covid and is caused by poor functioning of the autonomic nervous system, which regulates bodily functions such as heart rate, respiratory rate and blood pressure. Symptoms of PoTS might include palpitations, sweating and light-headedness which crucially appear on standing or sitting but improve when the patient lies down. PoTS is usually diagnosed in secondary care by means of a tilt table; the patient is strapped to a bed which tilts to a variety of angles and their pulse, blood pressure and symptoms are measured during the test. We don’t have tilt tables in primary care, but we can do a ten-minute stand test. Check the patient’s pulse and blood pressure when they are sitting down and then ask them to stand up. Recheck pulse and blood pressure immediately on standing and after two, five and ten minutes of standing. An increase in heart rate of at least 30 beats per minute (40 if the patient is aged 19 or under), with no blood pressure drop, suggests PoTS and would indicate a need for outpatient referral.7  

Your patient might want to know if you are going to arrange any tests. The NICE guidance on long Covid suggests that you might want to consider full blood count, renal, liver and thyroid function, CRP, ferritin and BNP testing. Other tests might be indicated depending on what symptoms the patient presents with. Some of the symptoms of long Covid are also indications for an HIV test (e.g. chronic diarrhoea, weight loss and peripheral neuropathy) and in any case any patient who lives in an area of high prevalence (this includes the whole of London) and is having blood tests for another reason should always be offered an HIV test if they haven’t had one in the last year.9  Pain in the bones or muscles may indicate vitamin D deficiency,10 so this may also be worth testing for. All patients with ongoing respiratory symptoms 12 weeks after their initial Covid infection should have a chest x-ray, but a normal x-ray does not rule out long Covid.

The future direction of care for your patient will depend partly on their symptoms, partly on the results of any tests done, and partly on how services are arranged in your area. Long Covid clinics should ideally have the capacity to investigate cardiac and respiratory symptoms; some have been criticised for focusing entirely on psychological management. A group of healthcare professionals with long Covid have reported ‘dyspnoea, dry cough, fever, anosmia and debilitating disease…[as well as] other symptoms never experienced before…we all share difficulties accessing adequate health-care services…some of us have received misguided assessment and treatment in…long Covid clinics and encountered dismissive behaviour from some health professionals’;11 listening to your patient in an empathetic manner and not dismissing their symptoms is an important part of the care that they receive. Consider signposting them to ‘your Covid recovery’ and to practical help from their union or ACAS12 if they are having problems at work. This first appointment is likely to be the start of a long journey back to (hopefully) normal health, so make sure that it is as positive an experience as possible for the patient.


  11. Gorna R, MacDermott N, Rayner C et al. Long COVID guidelines need to reflect lived experience. The Lancet 2020; 397(10273): 455 – 457

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