Since initial publication of this post in early 2020, a substantial body of research evidence has emerged to investigate the efficacy & safety of supportive care interventions for COVID-19 recovery. This information now lacks key updates within the scientific literature.
As novel coronavirus (COVID-19) continues to spread, there has been a lack of discussion of basic nursing interventions known to improve outcomes for other infections. Many caregivers have also reported concerns after coaching their loved ones through upsetting signs of COVID-19 at home, like difficulty breathing and extreme tiredness. It is predicted that the ability to manage symptoms in the community has a significant impact on hospitalization rates for COVID-19. The aim of this document is to support communities — especially health professionals — with knowledge on how best to manage coronavirus symptoms among adults (18 years or older) currently in isolation/quarantine.
This working document starts the work of building a framework for COVID-19 symptom management. Following a review of research literature, four pillars of COVID-19 symptom management were identified. The current framework draws inspiration from evidence-based Enhanced Recovery after Surgery (ERAS) principles, which have dramatically improved post-surgical recovery times using a set of routine supportive care practices.
This content is provided for informational purposes only and is not intended to be a substitute for the advice of a health professional.
Please refer to official government information to assess your current risk of exposure to COVID-19, and to access appropriate health supports in your area.
[Last Review: Mar. 22, 2020]
General Consensus | Home exercise is an important factor in preserving function during a period of acute pulmonary illness. At the same time, home exercise can be unsafe for some people depending on the severity of Novel Coronavirus (COVID-19) symptoms or cardiovascular risk. Family or friends should initially observe all physical activity from a safe distance (e.g. greater than 2 meters distance or via videoconferencing) and it should be possible to contact emergency services from the exercise setting. Low-intensity physical activity is recommended as an initial starting point for home exercise among persons managing symptoms of COVID-19. People should stop exercising immediately and call for medical attention if they experience the following symptoms:
- Rapid loss of breath/extreme breathlessness
- Cannot speak after a short rest period
- Feeling dizzy or faint
- Chest pain or symptoms of a heart attack
- Severe pain
- Feeling ‘off’
Does strenuous exercise lower viral immunity, increasing the risk that COVID-19 will progress?
In the early 1990’s, it was commonly believed that vigorous or endurance exercise created a brief period, or “open window” period, for contracting an upper respiratory tract infection (URTI). This continues to be discussed within the literature, primarily because it is known that cortisol (a stress hormone with immuno-suppressive functions) temporarily spikes in response to vigorous or endurance exercise. Key studies informing this hypothesis include epidemiological studies of distance runners. Compared to matched controls, it was found that runners who participated in a distance running event reported twice the amount of URTI symptoms in the two week period following the race. This finding was also confirmed across multiple large-scale observational studies of marathon runners in the late 1980’s. These findings suggested the existence of a “J-shaped” curve, where people who over-train experienced more frequent and severe symptoms of a URTI. The mechanism behind these changes are that the body is known to temporarily modulate non-specific immune responses in order to reduce the inflammatory response immediately following exercise.
However, it has been suggested more recently that other factors associated with strenuous exercise may actually have a greater influence on the development of URTI symptoms. For example, specific nutrient deficits — such as protein deficiency — can temporarily impair immune function. Other influencing factors include: fatigue, psychological stress (anxiety), exposures to pathogens and exposures to large crowds. Therefore, for the common cold, vigorous exercise does not independently increase the intensity of URTI symptoms when related factors are controlled. It remains unknown whether vigorous or endurance exercise would cause a worsening of viral symptoms for persons living with COVID-19.
Does exercise enhance the body’s ability to identify and kill cells infected with the SARS-CoV-2 virus?
Although there is limited information available on how SARS-CoV-2 — the infectious agent that causes COVID-19 — interacts with the host immune system, emerging data suggests that the virus activates a cascade of non-specific (innate) immune responses which contributes extensively to the development of inflammation and flu-like symptoms. This inflammatory response eventually leads to atypical pneumonia, and appears to also produce an acute decline in respiratory function. In some people, this progresses further to acute respiratory distress syndrome, or ARDS.
Emerging evidence suggests that SARS-CoV-2 will progress to a symptomatic COVID-19 infection when a person exhausts their supply of cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells, which are necessary for the effective control of new viral infections in the body. While individuals continue to have an inflammatory response, the virus itself appears to exhaust the antiviral component of both non-specific and specific immune responses.
Interestingly, a single bout of vigorous exercise is widely known to produce a profound rise in circulating lymphocytes. The rise in lymphocytes in peripheral blood is also one of most commonly reproduced findings in human exercise physiology. There is also known to be a dramatic but transient rise in the functional capacity of lymphocytes after vigorous exercise. Similarly, strong evidence supports the idea that exercise induces a state of “immune surveillance” for viral pathogens. So, while exercise does dampen the non-specific component of immunity, it does not appear to cause immune suppression within the acquired (specific) branch of immunity which is important to viral protection.
Therefore, vigorous exercise is likely to enhance a person’s immune system capacity in the short term by augmenting specific immune responses. This temporarily enhances the ability of the body to detect and destroy SARS-CoV-2 infected cells. Exercise also appears to reduce non-specific immune responses which, in turn, reduce the negative impacts from inflammation in the body. These positive impacts are likely counterbalanced by several functional limitations that the disease creates, making it difficult to exercise safely.
What are the risks of exercising with COVID-19 symptoms?
The main risk of exercise among people with respiratory illness is related to the added stress it can place on the body. Many people with flu-like symptoms report significant muscle aches, fatigue and exertion in response to simple movements like walking on level. In the case of COVID-19, there is the additional pressure of breathlessness among many people affected by the disease. These limitations are important, as a person can easily overload their cardiac or respiratory capacity during exercise. The main risk, therefore, is a serious cardiac or respiratory concern during exercise.
Extensive research supports the idea that early mobilization and therapeutic exercise — even while ventilated — can positively impact the course of Acute Respiratory Distress Syndrome (ARDS) in ICU. The positive effect of exercise on ARDS outcomes in ICU settings appears to be mediated by:
- Reversal of the process of Acute Lung Injury (ALI) induced muscle wasting
- Reduced systemic inflammation, by modulation of non-specific host defenses (lower neutrophilic influx into alveolar space, reduced GCSF and reduced cytokine expression)
- Increase in diaphragmatic strength, reducing the physical work of breathing at rest
- Improved blood flow (perfusion) to key structures within the lungs, improving gas exchange
Therefore, it is wise for a person exercising at home to initially have supervision (at a distance) by a family or friend. It is also important to have telephone access to emergency medical responders, should exercise induce a major event. To prevent these risks, exercise should initially be well-tolerated and not induce any significant distress. A review of evidence for ICU patients with ARDS found that low to moderate exercise intensity (5-25 min twice daily) seemed to be protective and induce significantly positive outcomes in a controlled setting.
Do home exercise programs exist for people with mild COVID-19 symptoms?
Yes. Low-intensity home exercise programs exist, and are especially safe when supervised (at a safe distance) by a care provider, family member or friend. The Canadian Centre for Activity and Aging has endorsed the Home Support Exercise Program, which is commonly used as a safe exercise program among older-adults with respiratory conditions in home care settings. Some exercises may need to be adapted to ensure safety among people living with COVID-19 symptoms.
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[Last Review: Mar. 25, 2020]
General Consensus | Difficulty breathing at rest or while lying flat may indicate an urgent respiratory condition requiring immediate assessment by a health professional. In the case of Novel Coronavirus (COVID-19), breathlessness is also a sign of more severe disease presentation. Shortness of breath at rest, in fact, is often accompanied by other severe symptoms. It is recommended to seek professional health advice if shortness of breath occurs at home.
If coping with shortness of breath at home, deep breathing is generally recognized as safe to reduce symptom distress. It is recommended to start with a deep breathing technique where the person breathes in deeply through their nose, and breathes out fully through their mouth. This is to ensure that the person completing deep breathing exercises will breathe out longer than they breathe in, while also providing an opportunity for full lung expansion. Forced expiratory methods are also generally known to improve obstructive processes associated with inflammation in the bronchi of the lung. However, these additional techniques may require coaching and professional support.
How do breathing exercises relieve shortness of breath from COVID-19?
Unlike other chronic respiratory conditions (like COPD or asthma), COVID-19 typically progresses to atypical pneumonia. This type of pneumonia is often called “walking pneumonia” as it can be accompanied by few respiratory secretions and a non-productive (dry) cough. If a chest computed tomography (CT) scan is performed on a person at this stage of COVID-19 infection, ground glass opacities are likely to be visible. These opacities — small black voids within the lung — are likely caused by alveoli and other air spaces of the lungs filling with fluid as a side-effect of a severe inflammatory response. Much like an acute exacerbation of COPD, this is likely a neutrophil-mediated inflammatory response.
Because of the pathophysiology of COVID-19, persons suffering from shortness of breath are not likely to require help clearing thick secretions from the lungs, nor do they need to improve the effectiveness of their cough. Instead, the primary goals of breathing exercises among a person with COVID-19 include improving lung capacity by:
- Promoting drainage of transudate (thin, clear fluids) within the alveoli
- Reversing obstructive processes (trapped air) due to bronchoconstriction and inflammation of the lung
- Improving perfusion (circulation) to inflamed areas of the lung
The primary goal of respiratory exercises, therefore, is to adapt breathing to accommodate an acute inflammatory response in the lung.
What breathing techniques can help manage shortness of breath symptoms from COVID-19?
Many breathing techniques exist to manage breathing difficulties. Especially if wheezing is present, one effective strategy is to combine abdominal breathing with pursed-lip breathing — see Video Example 1. This combined breathing technique can help someone to catch their breath.
Another powerful breathing exercise that is easily taught is the Active Cycle of Breathing Technique (ACBT)— see Video Example 2. This strategy was designed to help to clear mucous from the the lungs, although it may also have an effect on clearing thin fluids (transudate) that is common with COVID-19 infection.
ACBT breathing consists of 3 phases:
- Breathing Control
- Deep Breathing
- Huffing or Controlled Coughing
Breathing Control | Breathing control helps relieve chest tightness and symptoms of panic by giving people back conscious control over their breath. The primary goal is to start by decreasing the sense of panic, and then helping the person regain control over their breathing pattern. It is recommended to continue practicing breathing control until a person feels more able to control their breathing, and relaxed. If someone cannot catch their breath after some time, urgent medical attention is warranted.
Basic Strategies for Breathing Control
- If you can, breathe in and out gently through your nose.
- If you must breathe through your mouth, try breathing with ‘pursed lips’ to increase the time spent in expiration.
- Let go of any muscle tension with every breath out. Relax your your shoulders with each breath out.
- Slowly, with each breath, try to slow your breathing rate.
- Relax and focus on your breathing. Try closing your eyes to focus on your breathing more effectively.
Deep Breathing | Deep breathing exercises promote maximal inspiration to help expand the lungs. This is known to increase blood oxygenation as well as induce a relaxation response in the body. Deep breathing exercises are usually enhanced with coaching from a trained health professional such as a Respiratory Therapist, nurse specialist or physiotherapist.
Basic Strategies for Deep Breathing
- Continue to relax your muscles with every breath out. Focus on relaxing your chest muscles (ribs) and shoulders as you breathe out.
- Take a long, slow, deep breath in your nose.
- After breathing in fully, hold the air in your lungs for about 3 seconds before breathing out.
- Without forcing the air out, breathe out with relaxed muscle tone. Do not force the breath out, so it sounds like a sigh.
- Repeat 3 – 5 times. If feeling light-headed, go back to the breathing control (1st step) of the cycle.
Huffing or Controlled Coughing | In the case of COVID-19, huffing may help displace transudate (thin, clear fluids) within the alveoli into the bronchioles where they can be coughed up as sputum. Huffing is simply a forced (strong) expiration, where there person breathes forcefully out with an open cough (like they are trying to fog up a mirror). People can try different intensities of huffing. However, this final stage of breathing often induces productive coughing. Producing phlegm which is a sign of effective huffing technique, or forced expiration, and is encouraged.
Are there other more advanced breathing strategies that a health professional can administer?
Aside from medication therapies, a physiotherapist trained in respiratory care can provide advanced chest physiotherapy modalities to persons with acute respiratory symptoms related to atypical pneumonia. Postural drainage is a promising intervention for persons with COVID-19 related shortness of breath.
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Management of Fever
[Last Review: Mar. 23, 2020]
General Consensus | Most mild cases of Novel Coronavirus (COVID-19) produce a fever and dry cough. It is important to note that people with COVID-19 who have fever are highly contagious, even if they suppress fever with medication. Rest and other supportive care strategies are commonly recommended during this period. This includes preventing dehydration by consuming plenty of fluids, and monitoring for urgent signs (e.g. acute confusion, seizures or loss of consciousness) which require assessment by a medical professional. There is currently scientific debate on whether or not it is helpful to suppress mild-to-moderate fevers (body temperature ≤ 39.9 °C) with certain NSAIDs — like ibuprofen — among persons with COVID-19. However, in cases where an adult develops a core body temperature exceeding 40.0°C (104.0°F) or when they are short of breath at rest, it is recommended to take immediate action to reduce fever symptoms.
Generally safe interventions to alleviate fever symptoms include:
- Wearing light clothing and removing heavy blankets
- Applying a cool cloth to the forehead
- Promoting adequate intake of clear fluids
- Using OTC medications as directed to reduce fever
- If shivering, using a blanket to reduce shivering. (Shivering increases body temperature and places increased metabolic demands on the body.)
Does fever help or harm the body’s ability to clear viral infections?
In response to cellular damage as well as the actions of specific immune system cells, the body will commonly undergo an acute phase prior to the onset of fever. This response occurs after the release of acute phase proteins into the blood. Acute phase proteins — also known as cytokines — are sensed quickly within the bloodstream by the hypothalamus. The hypothalamus is a small part of the brain that regulates body temperature, among other things. Because many cytokines start a cascade of inflammatory responses within the body, fever is typically accompanied by other flu-like symptoms like muscle aches. In most cases, a mild-to-moderate fever will work in tandem with other inflammatory processes to help the body to clear a viral infection.
Across a broad selection of animal species, fever is generally considered to be a protective immune response against viral infection. Hippocrates had even claimed that he could heal any disease if only he could provoke a fever. (It is worthy of note that infectious diseases were a commonly untreatable medical concern in Ancient Greece.) Provoking someone to live with a low-grade fever over an extended period of time is also known to enhance the clearance of some viral pathogens, like Hepatitis C. Finally, emerging research on viral pneumonia (e.g. Influenza-like Illness) also encourages a permissive approach to treating fever symptoms in order to enhance the immune system response to illness.
Is it dangerous to not treat a mild fever if I have symptoms related to COVID-19?
It depends. Febrile illness will dramatically increase the metabolic demands placed on the body and, therefore, oxygen and caloric demands. As a result, sustained symptoms of fever are potentially dangerous for people experiencing:
- Core body temperature > 40.0°C (104.0°F)
- Shortness of breath at rest
- Dehydration or malnutrition
- Heart or lung disease
- Acute neurological concerns (e.g. brain injury or stroke)
- An inability to sleep
- Severe, disabling symptoms
- Other medical conditions, such as endocrine disorders
Fever may also present additional risks for people suffering from acute kidney injury following a period of dehydration. In many of these cases, it is recommended to consult with a health-care provider via phone for specific management advice.
On the other hand, a growing number of researchers assert that a mild-to-moderate fever between 38.0 – 40.0°C (100.0 – 104.0°F) may be protective for most patients. A randomized controlled trial was initiated on antipyretic treatments and its impact on clinical outcomes in ICU. It is noteworthy that this trial was halted prematurely after interim data analysis because there were 7 deaths within the aggressively-treated fever cohort (multiple interventions for fever > 38.5°C ) compared to only 1 death in the permissive fever cohort (treatment initiated when temperature > 40°C). Other studies have found no significant difference in clinical outcomes among patients who received antipyretic treatment, suggesting treatment to suppress fever does not improve clinical outcomes among most acutely-ill patients. Finally, although high-grade fevers commonly cause seizures among children, there is limited evidence that the use of antipyretics actually prevents these complications.
Is ibuprofen safe to take for fever symptoms related to COVID-19?
The safety of non-steroidal anti-inflammatory drugs (NSAIDs) — including ibuprofen — for treating COVID-19 symptoms is currently unknown. For people already prescribed NSAIDs, they are encouraged to continue taking these medications until they can speak with a medical professional. That said, some experts within the U.K. and Europe have recommended against use of anti-inflammatory medications (specifically, ibuprofen) based on anecdotal associations between high-dose NSAID use and more severe trajectories of COVID-19 illness among young adults in France. On Mar. 23, 2020, the European Medicines Agency clarified that the use of ibuprofen for the control of COVID-19 symptoms remains under investigation. Until these questions are answered, other OTC medication options (like acetaminophen) could be a safer first-line option for fever suppression in COVID-19.
Prior to the onset of COVID-19, there have been documented concerns with the cardiovascular, gastrointestinal and renal safety profile of many NSAID’s when used above the maximum recommended dosage. There has also been research into the use of anti-inflammatory medications among people facing infection with traditional coronaviruses. The immune response against other coronaviruses are typically mediated by mast cells, which release cytokines and other inflammatory factors to isolate the virus in lung tissue. NSAIDs, on the other hand, work by inhibiting the cycloxygenase enzyme which in turn reduces mast cell activity in lung tissue.
While this temporarily helps to reduce inflammation alongside fever, the use of NSAIDs may also mildly reduce the ability of mast cells to respond to novel pathogens in lung tissues. It is yet unknown whether this produces a net positive or negative effect on the course of the disease. Since the majority of COVID-19 cases do not result in death, subtle changes in morbidity and mortality are not easily detected. However, emerging evidence suggests the sustained use of anti-inflammatory drugs could increase morbidity and mortality for other (non-COVID-19) viral pneumonias.
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[Last Review: Mar. 28, 2020]
General Consensus | Specific nutrient deficiencies are known to impact the immune response to viral pathogens, including Novel Coronavirus (COVID-19). Especially within northern climates, many people are Vitamin D deficient and can benefit from taking a Vitamin D supplement. Correcting specific nutrient deficiencies — particularly Vitamin D serum levels — is generally recognized as safe and effective at augmenting the natural immune response within the body.
Emerging data also suggests that COVID-19 infection may reduce a person’s ability to smell and taste food, potentially making food less palatable. This is of concern because severe flu-like symptoms associated with COVID-19 are likely to produce mild-to-moderate anorexia and dehydration. If COVID-19 also affects taste and smell, it is generally accepted that fever symptoms would be accompanied by significantly reduced food and fluid intake. This is expected to significantly increase the risk of malnutrition occurring during the acute period of COVID-19 infection. It is highly recommended for persons with flu-like symptoms from COVID-19 to:
- Consume plenty of clear fluids through the day.
- Consciously seek out high-protein foods, even if not hungry.
- Consider the value of trying stronger-flavored or bland foods if your usual go-to foods suddenly taste unpleasant.
Does a short period of malnutrition lower the body’s ability to fight COVID-19 infection?
Yes. Malnourished patients are more vulnerable to viral infection, and are also more likely to have a more severe course of Influenza-like Illness. Protein-calorie malnutrition also has a significant cumulative impact on immune response. Malnutrition resulting in protein catabolism (breakdown) results in an immediate reduction in the number of circulating B and T lymphocytes within the blood. The production of key inflammatory proteins — such as IL-6 and TNF-α — is also significantly reduced when protein catabolism occurs. Both lymphocytes and inflammatory proteins are necessary for a sustained viral response in the body.
Malnutrition is associated with worse clinical outcomes and increased risk of death among persons with active Influenza infections. Similarly, among patients who were provided with supplemental protein, their viral immune response is known to be significantly stronger against common pathogens. This effect is well-documented, particularly as a cause of primary immune deficiency within developing countries with food scarcity. Among severely malnourished patients, almost all host immune responses are diminished.
Among patients who died from COVID-19 infection, emerging data about their patient characteristics also appears to the significant role that nutrition plays in disease recovery. This is an expected finding, as both the action and expression of lymphocytes is significantly reduced during periods of malnutrition. Paradoxically, the innate immune response (particularly inflammatory proteins such as IFN) are can cause anorexia and protein catabolism, or breakdown. This response generally results from the interaction of inflammatory proteins with the hypothalamic-pituitary axis, causing the release of multiple proteins including leptin and catecholamines. While this stress response can promote healing of damaged tissues and neutralization of ROS over time, it also leads to loss of appetite, muscle breakdown and immunosuppression.
At the same time, protein overload is also not beneficial. Multiple studies of Acute Respiratory Distress Syndome (ARDS) in ICU settings have found that early enteral feeding is actually associated with worse clinical outcomes. There is also no evidence that the early initiation of parenteral (IV) nutrition among persons hospitalized for ARDS has any benefit on clinical outcomes. Protein-calorie supplementation appears to augment the body’s natural immune response to viral respiratory illnesses. Similarly, malnutrition is associated with worse outcomes in this group.
Despite the positive clinical impact of protein-calorie supplementation on acute respiratory infections, overfeeding is not recommended. Overfeeding, in fact, has been known to suppress autophagy. Autophagy is a key cellular repair process whereby cells “eat” themselves as a means to rebuilding healthier cells and tissues. While the significance of suppressing autophagy remains up for debate, it is hypothesized that overfeeding prevents the body from clearing intracellular damage through this process. Therefore, one promising area for the treatment of COVID-19 related malnutrition is inducing a rapid-cycling fasting state where a person has a bolus intake of high-protein meals amidst short (3 hour) fasting periods during the day. It is currently unclear, however, whether this approach would improve or worsen clinical outcomes.
Can some nutritional supplements improve the immune response against COVID-19?
While there is much speculation on particular micro-nutrients that may help fight COVID-19, there is limited clinical data available from which to draw any solid conclusions. There are, however a few emerging perspectives within the research literature on COVID-19:
- Antioxidant Support. The pathophysiology of the SARS-CoV-2 virus (COVID-19) is complex. However, one key process associated with COVID-19 infection is that neutrophils eventually move into the lungs, releasing Reactive Oxygen Species (ROS) in the process. These chemical mediators damage cellular tissues, in turn producing a stronger inflammatory response. While this is often effective for bacterial infections, the non-specific immune response tends to be an inefficient method for fighting viruses in the lower respiratory tract. Antioxidants are likely to neutralize ROS somewhat, and are mentioned as a possible intervention to preserve lung function as COVID-19 progresses. Many potent antioxidants come from food, including colourful vegetables and fruit.
- Zinc. Although it is currently unknown whether hydroxychloroquine (HCQ) can effect a COVID-19 cure, one scientific explanation is that HCQ appears to alter cellular uptake of zinc within infected cells in the lung. There is extensive study of the effect of zinc lozenges on reduction in the frequency and severity of traditional coronavirus infections, and it appears that zinc does have some positive impact on recovery from the common cold. Emerging laboratory research also suggests that zinc may inhibit the replication of SARS-CoV-2 RNA, among other things.
Other theories have cited the positive potential of specific nutraceuticals (e.g. Vitamin C, Melatonin, Selenium, Astralagus, Ginger root, Ginseng) which are largely based on comparative physiology. As a result, the use of other supplements in the context of COVID-19 should be discussed with a health professional and remains of unknown clinical significance. While the science behind the SARS-CoV-2 virus continues to be investigated, it is possible that these supplements may help. However, it is also possible that the use of specific natural health products may cause a more rapid progression of COVID-19. For these reasons, adjunct treatments and nutraceuticals are not mentioned in the ERACE working document at this time.
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