Capital Science Lectures | Issue 790: Improving the public's scientific literacy and building a strong health barrier for the elderly

This article is from the Capital Science Lecture Hall, which is hosted by the Beijing Association for Science and Technology, organized by the Beijing Science Center, and co-organized by the Beijing Science and Technology Newspaper. The lecture hall invites academicians and experts to give lectures every week to promote the scientific spirit, help the public establish scientific thinking, master basic scientific methods, and understand necessary scientific knowledge.

The COVID-19 pandemic has raised public awareness of health and made people fully aware of the importance and necessity of improving scientific literacy. How can the elderly recover scientifically after "Yang Kang"? How can we protect people's lives and health to the greatest extent?

This issue of Capital Science Lecture Hall invites Xu Zuojun, chief physician and professor of the Department of Respiratory and Critical Care Medicine of Peking Union Medical College Hospital, to authoritatively explain to the public how the elderly and their families should respond to the epidemic scientifically and jointly build a strong health barrier for the elderly.

Speakers:

Xu Zuojun, Chief Physician and Professor, Department of Respiratory and Critical Care Medicine, Peking Union Medical College Hospital

Symptoms of COVID-19 infection in the elderly

After being infected with the new coronavirus, most patients will experience symptoms such as fever, headache, body aches, fatigue, dry throat, etc. As the disease progresses, the body temperature will gradually return to normal after 3-5 days, and the general discomfort will gradually ease. During this process, upper respiratory tract symptoms may occur, such as nasal congestion, runny nose, cough, and decreased sense of smell and taste. The symptoms of the elderly and young people are basically the same, but they also have some of their own characteristics. For example, due to the poor reaction ability of the elderly, some cases only show low fever, so the severity of the disease cannot be judged by the temperature of the fever.

Some patients are asymptomatic or have only mild upper respiratory tract symptoms, such as sore throat, nasal congestion, runny nose, cough, etc. A small number of patients develop dyspnea and hypoxia symptoms one week after the onset of the disease, and even develop respiratory failure and multiple organ failure, and develop into severe or critical patients.

After being infected with the novel coronavirus, the elderly should focus on self-monitoring in five aspects. First, self-feeling, to see if there are symptoms such as fatigue, soreness, sore throat, nasal congestion, etc.; second, monitor body temperature, pay attention to whether the armpit temperature exceeds 37°C; third, monitor pulse, the normal pulse of a person is 60-100 beats/minute, if there are symptoms such as hypoxia and fever, the pulse will obviously increase; fourth, monitor breathing, the normal breathing frequency is 12-16 times/minute, when hypoxia and lung infection occur, breathing tends to become faster, can reach 18-20 times/minute, or even faster, which will cause breathing difficulties; fifth, monitor blood pressure, the normal blood pressure is 120/80 mmHg, the novel coronavirus infection may cause septic shock in patients, causing low blood pressure.

Clinically, COVID-19 infection can be divided into four types. Mild cases are mainly characterized by upper respiratory tract infection, with symptoms such as dry throat, sore throat, cough, and fever. Moderate cases are mainly characterized by persistent high fever for more than 3 days, or cough, shortness of breath, etc., but respiratory rate (RR) < 30 times/min, oxygen saturation > 93% when breathing air at rest, and characteristic COVID-19 pneumonia can be seen in imaging. Mild cases generally do not develop pneumonia, and moderate cases begin to develop milder pneumonia.

▲Self-monitoring methods for novel coronavirus infection (Photo provided by Xu Zuojun)

When any of the following conditions are met and cannot be explained by other reasons other than COVID-19 infection, the patient can be diagnosed as severe. These symptoms include: shortness of breath, respiratory rate (RR) ≥ 30 times/min; oxygen saturation ≤ 93% when breathing air at rest; arterial oxygen partial pressure (PaO2)/oxygen concentration (FiO2) ≤ 300 mmHg (1 mmHg = 0.133 kPa); clinical symptoms progressively worsen, and lung imaging shows significant progression of lesions > 50% within 24-48 hours.

When a patient has respiratory failure and requires mechanical ventilation, is in shock, or has other organ failure requiring intensive care unit (ICU) treatment, he or she can be diagnosed as a critically ill patient if any of these conditions occur.

The above are the specific standards for the clinical classification of the new coronavirus. It is very necessary to determine the classification for the treatment of patients, especially to formulate appropriate treatment strategies.

How to treat mild symptoms

For patients with mild COVID-19, respiratory tract infection is the main symptom. Those with high fever can use physical cooling and antipyretic drugs; those with severe cough and sputum can take antitussive and expectorant drugs. In addition, attention should be paid to ensuring adequate energy and nutritional intake, water and electrolyte balance, and maintaining a stable internal environment.

▲Drug treatment for mild COVID-19 infection (Photo courtesy of Xu Zuojun)

For the treatment of elderly COVID-19 patients, special attention should be paid to the key points of medication. For the elderly, since most patients suffer from multiple diseases at the same time, they need to take multiple drugs, which is prone to drug interactions and adverse reactions.

At the same time, the structure and function of the elderly's systems, organs, and tissues change, and their ability to tolerate, detoxify, excrete, and resist drug side effects is greatly reduced, and they are more likely to have adverse reactions when taking certain drugs. Therefore, the elderly need to pay special attention to the following points when taking medication.

The first is the principle of individualization, that is, individualized drug dosage treatment is carried out according to the age and weight of the elderly. The drug instructions usually indicate the conventional dosage, but the effect of a 30-year-old patient taking 500 mg of the drug and a 90-year-old patient taking 500 mg of the drug is obviously different, so treatment should be individualized as much as possible.

The second is the principle of priority treatment. Priority treatment means focusing on the main contradiction. For example, if an elderly person is infected with the new coronavirus and also has coronary heart disease, hypertension, or lung disease, the doctor needs to determine what the patient's main problem is and then give priority treatment. For other stable diseases, if the drugs do not interfere with each other, they can continue to be used. However, if priority treatment is needed for the new coronavirus infection, some other drugs can be postponed.

Another principle is to keep medication simple. The simpler the medication for the elderly, the better. If one medication can be used, try not to use two.

The second principle is to reduce the dosage of the drug. For patients with liver and kidney dysfunction and older people infected with the new coronavirus, the dosage of the drug can be appropriately reduced.

Finally, there is the principle of dietary adjustment. Because the absorption of some drugs may be related to diet, it is necessary to make some appropriate adjustments to the patient's diet.

Critical care for the elderly

The elderly are a high-risk group for developing severe COVID-19 and death. This is related to factors such as decreased immunity due to aging, decreased ciliary mucus clearance ability leading to decreased lung defense function, and the coexistence of multiple diseases.

People aged 65 and over, residents of nursing homes, those who have not been vaccinated against COVID-19, people with chronic diseases (cardiovascular disease, chronic kidney disease, diabetes, neurocognitive disorders, obesity, etc.), and people with various forms of immunosuppression (tumor radiotherapy and chemotherapy, organ or hematopoietic stem cell transplantation, congenital immunodeficiency, HIV infection, hormone/immunosuppressant/biological agent users, etc.) are prone to developing severe or critical illness. In addition, patients with liver disease and pregnant women are also at high risk of developing severe COVID-19.

▲People at high risk of severe COVID-19 (Photo provided by Xu Zuojun)

For elderly patients with severe COVID-19 infection, a variety of treatment methods can be used. The first is general treatment. Attention should be paid to monitoring the vital signs of the elderly, especially the oxygen saturation at rest and after activity, and the indicators related to the underlying disease should be monitored at the same time. Necessary laboratory tests, such as blood routine, urine routine, and biochemical indicators can also determine the severity of the disease. In order to prevent hypoxia, standardized and effective oxygen therapy measures should be given according to the condition of the elderly.

Antimicrobial drugs (antibiotics) should also be used for severe patients, because it is possible that after being infected with the new coronavirus, the patient's immune function will be further reduced, resulting in secondary bacterial infection. However, blind or inappropriate use of antimicrobial drugs should be avoided, especially the combined use of broad-spectrum antimicrobial drugs. At the same time, patients with underlying diseases should also be given corresponding treatment to prevent a worse prognosis.

In addition to general treatment, antiviral treatment is also a very important part of the treatment process. Because the elderly have a relatively weak ability to clear viruses, once the elderly are diagnosed with infection and the virus is still replicating in their bodies, antiviral drugs should be used as soon as possible, such as the combination package of namatevir tablets/ritonavir tablets (Paxlovid), azithromycin tablets, monoravir capsules, etc. In addition, there are some other methods of antiviral treatment, such as COVID-19 human immunoglobulin and convalescent plasma from recovered patients, which are also effective for patient recovery.

It is worth noting that Paxlovid has contraindications with many other drugs. Taking the table below as an example, the green part means that there is no contraindication with Paxlovid and it can be used at the same time; the red part means that there is a contraindication, that is, if Paxlovid is used, in principle, the drugs in the red area cannot be used; the pink area means use with caution; the yellow part means that it can be used, but special attention needs to be paid when using it.

▲Paxlovid incompatibility (Photo courtesy of Xu Zuojun)

During immunotherapy for elderly patients infected with COVID-19, glucocorticoids and interleukin-6 (IL-6) inhibitors are often used to reduce excessive immune damage to the body. In addition, anticoagulant therapy is used because COVID-19 not only damages the respiratory system, but also causes abnormal coagulation mechanisms and blood clots. In this case, preventive doses of anticoagulant therapy are routinely given to critically ill patients to improve their prognosis.

In addition, there is prone ventilation therapy. The specific operation method is to let severe COVID-19 patients lie face down to rest, which can improve oxygenation status. It is recommended to do this for no less than 12 hours a day.

Psychological intervention is also essential in the treatment of critically ill patients. When patients are overly nervous and anxious, psychological counseling should be strengthened and supplemented with drug treatment when necessary.

Scientific recovery after "Yang Kang"

Some time ago, after experiencing the peak of the epidemic, many people were in a state of "positive health". Some people's discomfort symptoms disappeared quickly, but for some people, the discomfort symptoms lasted for a month, two months, or even longer, so there is now a concept called "long COVID-19 syndrome". For example, some people have "positive" and although the virus has been cleared from their bodies, they still have symptoms such as coughing, sputum, muscle aches and bone pains all over the body, feel short of breath after a little activity, and even have myocarditis.

Regarding the question of whether people who have tested positive still need to wear masks when going out, at present, even if they have tested positive, it is best to keep the habit of wearing masks. After testing positive, the antibodies in the body can basically last for 3-6 months, which means that the chance of being infected with the same virus again in 3-6 months is small, but not absolutely impossible. In clinical practice, we have encountered very few patients who were infected again 2 or 3 months after being tested positive.

How to judge whether a patient has developed viral pneumonia and whether he needs to take antibiotics? Generally speaking, doctors can tell whether a patient has developed pneumonia through chest CT scans. Antibiotics are generally not needed for viral pneumonia. If there is a concurrent bacterial infection, antibiotics can be used.

How should we deal with the appearance of lung nodules? Do we need to take medicine? Nodular lesions in the lungs are sometimes caused by the new coronavirus. In this case, the virus should be treated. However, it is not ruled out that organizing pneumonia may occur after infection with the virus. In this case, glucocorticoids should be considered for treatment.

In addition, during intensive care treatment, patients and their families are worried about the appearance of "white lung". Generally speaking, when the inflammation of the lungs is severe and there is a lot of exudate, that is, when the white image area reaches 70%-80%, it is colloquially called "white lung" in clinical practice. Therefore, not all cases of lung inflammation are "white lung".

Some people cough for more than 3 weeks after "Yang Kang", but as long as there is no fever, no yellow sputum, and low white blood cell count, a little cough is normal and you don't need to be too nervous. If you feel that the cough is uncomfortable, you can use some cough medicine to relieve it.

Many people feel weak, easily fatigued, and even short of breath when walking after recovery. After these symptoms appear, the most important thing is to confirm whether there is a problem with the body. For example, you can take a chest CT scan first. If there is indeed a lesion in the lungs, then treatment is required.

However, if you experience chest tightness and shortness of breath, but your heart and lung tests are normal, then this is a symptom of "long COVID-19". After a period of rest, the symptoms may gradually subside. Therefore, if you experience the above symptoms, don't be overly nervous. Psychological adjustment is very important.

The same applies to symptoms such as sweating and muscle aches after treating "Yang Kang". As long as there is no obvious lesion in the body, the discomfort symptoms may disappear over time.

▲Function of the respiratory system (Photo provided by Xu Zuojun)

Regarding the question of how to resume exercise after "Yang Kang", there are two situations. If the patient's lungs have fully recovered and there are no obvious symptoms such as coughing and shortness of breath, normal activities can be carried out. However, if the lungs have recovered to normal and you still feel short of breath after activities, try not to do strenuous exercise. Because the lungs are an important organ for gas exchange, exercising when the lungs have not fully recovered will increase oxygen consumption and further aggravate hypoxia. Therefore, it is recommended that you wait until your body has fully recovered before doing scientific exercise.

(This issue’s pictures and videos are from the 790th Capital Science Lecture)

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