Ischemic Stroke and Covid-19
“Typical” Covid-19 Symptoms
When people think of Covid-19 symptoms, they rightly think of the more common symptoms like fever, chills, cough, difficulty breathing, fatigue, headache, muscle aches, a loss of taste or smell (anosmia), nausea, vomiting, or diarrhea .However, there are a variety of neurological symptoms and syndromes (a collection of symptoms in a particular pattern) that have been discovered to occur due to Covid-19. Curiously, not all people who have serious neurological syndromes from Covid-19 have very prominent or severe “typical” symptoms.
What are the Neurological Syndromes seen with Covid-19?
Even though Covid-19 is thought of as a respiratory – or lung – disease, one of the most common symptoms is actually thought to be due to a neurological problem: a loss of smell, or anosmia. While it is not fully understood, the current theory is that the Covid-19 virus causes a problem with the function of the olfactory sensory neurons, which are the nerve cells responsible for transmitting smells to the brain. This anosmia commonly is only temporary, but it can persist. This can lead to a loss of appetite and weight loss, as the sense of smell is highly associated with taste and food intake.
A much more rare and possibly life threatening neurological syndrome is one called hemorrhagic necrotizing encephalitis due to Covid-19. In this condition, there is significant severe inflammation in the deeper portions of the brain and brainstem, often with bleeding within those areas. This causes the person to have profound confusion, become lethargic or comatose, have difficulty breathing, seizures, and more. It is important for medical providers to suspect this and evaluate for it, as treating it early with steroids or other immunotherapies can result in a full recovery in an otherwise deadly process. MRI of the brain, lumbar puncture for cerebrospinal fluid analysis, and other testing may be used.
Like other viral illnesses, occasionally people who have Covid-19 can have a delayed inflammatory condition affecting the peripheral nerves, called Guillain Barre syndrome. This causes abnormal sensation (sometimes a “pins and needles” feeling) in the hands and feet and progressive weakness of the extremities with a loss of reflexes. This can be treated with immunotherapies and physical therapy. EMG (nerve and muscle testing), lumbar puncture, and imaging of the spinal cord and brain may be necessary to make this diagnosis.More and more, ischemic stroke is being tied to Covid-19. We will focus on this neurological manifestation of Covid-19 now.
Covid-19 and Stroke Risk
Research has shown that people Covid-19 have a higher risk of ischemic stroke – damage to the brain from a lack of blood flow causing the brain to not have enough oxygen and glucose – than the average population. About 1.3% of people who test positive with Covid-19 have had an associated stroke. This is much higher than other viruses such as influenza.
In a large stroke database – the Get With The Guidelines registry – various information was analyzed on Covid-19 patients who had stroke in 2020. This showed that these stroke patients were younger, had more severe strokes, had more disability, and had a higher rate of death than stroke patients who did not have Covid-19. This shows the importance of further studying this phenomenon and taking steps to improve care.
How does Covid-19 Cause Stroke?
Covid-19 has been shown to cause stroke through a variety of mechanisms.
This virus causes significant inflammation in the body. This includes the inner linings of blood vessels – the endothelium – which can cause small blood vessels to spasm or tighten down. This can cause the brain in that region to not have enough blood flow.
Covid-19 can also cause certain people to be more likely to form blood clots in various parts of the body. This is called a “hypercoagulable state.” This can result in blood clots in the veins of the leg (called a Deep Vein Thrombosis or DVT) or the lungs (called a Pulmonary Embolism or PE), but in the case of Covid-19 it can also cause a blood clot (or thrombus) to form in the arteries of the head or neck, such as the carotid artery. The carotid artery is the large artery in the front part of a person’s neck on either side of the larynx or “Adam’s apple.
There are also indirect ways that Covid-19 causes stroke, as when it affects the heart. The virus has several negative effects on the heart, some of which can affect the brain. Covid-19 can cause a cardiomyopathy where the heart muscle does not pump or empty the chambers of the heart well, leading to risk for a blood clot forming and then dislodging to travel to the brain. It also can cause the heart to go into an abnormal heart rhythm called atrial fibrillation where clots can form in the top chamber of the heart and then travel to the brain. As this is a new and evolving virus, there are likely other ways that Covid-19 increases stroke risk that have yet to be fully discovered or described.
Tests to Assess Risk of Stroke in People with Covid-19
If a person has Covid-19 severe enough to require hospitalization and risk of stroke, typically a variety of tests will be performed to assess risk.Certain blood tests such as c-reactive protein, erythrocyte sedimentation rate, and ferritin will be checked to assess the level of inflammation in the body.
Other blood tests such as d-dimer, fibrinogen level, and cardiolipin antibodies will be checked to assess how likely the person is to form blood clots.
An ultrasound of the heart – or echocardiogram – will be done to assess heart function. EKG and cardiac monitoring will assess for any abnormal heart rhythms such as atrial fibrillation.
If a person has stroke-like symptoms – balance problems, problems with vision, a facial droop, arm or leg weakness or numbness, slurred speech or difficulty getting words out – it will be important to get a CT of the head to assess for any bleeding and imaging of the blood vessels of the head and neck to look for any clots.
Treatments in Covid-19 Patients to Prevent Stroke
Depending on various factors including the above testing, measures can be taken before a person has stroke-like symptoms in order to try to lower stroke risk.
If a person has stroke-like symptoms – balance problems, problems with vision, a facial droop, arm or leg weakness or numbness, slurred speech or difficulty getting words out – it will be important to get a CT of the head to assess for any bleeding and imaging of the blood vessels of the head and neck to look for any clots.
Treatments for Stroke in Covid-19 Patients
The treatments for acute ischemic stroke – or those started as soon as a stroke is recognized – are currently similar for strokes due to Covid-19 as those that are not. Thrombolytics – or clot busting medications – can be given if the person seeks care soon enough after symptoms start.If there is a blockage found in a large blood vessel, a procedure called a thrombectomy can be performed to use a device placed within the artery to suction or pull the clot out and restore blood flow.
If there is a blockage found in a large blood vessel, a procedure called a thrombectomy can be performed to use a device placed within the artery to suction or pull the clot out and restore blood flow.If blood tests show the person is in a hypercoagulable state, strong blood thinners or anticoagulants may be started much sooner than typical after stroke to help prevent another stroke.
Do Not Avoid Treatment for Stroke-Like Symptoms Due to Fear of Covid-19
Early onset of physical therapy, occupational therapy, and speech therapy should still be pursued with a focus on early rehab after stroke with Covid-19. These patients should not be alone without the services offered to other stroke patients, as they can benefit from these interventions.
During a pandemic, there is an understandable tendency to want to avoid or delay seeking medical care. This may be due to concern over being exposed to other people who may have Covid-19, to avoid exposing others if the person is known to have Covid-19, or to want to not burden a healthcare facility that is already straining in the setting of the pandemic.
To address these concerns, fortunately emergency departments and hospitals now have the proper protocols and supplies to help reduce risk of spreading Covid-19 among patients or staff, have a better supply of proper protective equipment, and have appropriate staffing to offer medical care to all.
It is particularly important to immediately seek care in the setting of stroke symptoms. Two treatments mentioned above – the thrombolytic clot busting therapies and clot-removing thrombectomy – are both very time sensitive treatments. If a person comes to the hospital too long after stroke symptoms, they may no longer be a candidate for any treatment and the damage may already be done. In the world of stroke, “time” is brain in the sense that the longer a stroke goes untreated, the more brain cells die, and the less treatment options are available. This is no different in a pandemic.
How is NeuroX Particularly Well-Suited for Helping People with Stroke and Covid-19?
As an advanced tele-medicine service, NeuroX is perfect for helping people with stroke and Covid-19. The technology can be used to offer Stroke Neurology expertise from a safe remote location in an emergency department, virtual video follow-up in a rehab facility that may not allow visits for people who are quarantined for Covid-19, and outpatient clinic follo- up that would otherwise have to be delayed due to quarantine policies and restrictions. With NeuroX, the stroke expert can safely evaluate and treat you wherever you are, despite Covid-19.
