Risk of stroke during peak hot weather.

At this time, the efficiency of blood pumping to the organs in the body, including the brain, is reduced. A person who has been outdoors in hot weather and suddenly enters a cold room is also at risk of stroke, because blood vessels constrict suddenly, increasing blood pressure.

Heatstroke, if not detected and treated promptly, can exacerbate risk factors and potentially be life-threatening or lead to severe long-term consequences such as speech impairment, paralysis, and lifelong disability. Therefore, early recognition of heatstroke symptoms, or those caused by other factors in general, is crucial and determines the patient's chances of survival.

Here are some signs that may indicate someone is having a heatstroke: headache, dizziness, blurred vision, high body temperature but no sweating, numbness or weakness, weakness on one side or the whole body, facial asymmetry, seizures, rapid heartbeat, shallow breathing, mental disturbances, disorientation, fainting… This may be followed by circulatory collapse and coma.

Without prompt medical attention, people who suffer heatstroke may face life-threatening risks.

Besides the risk of stroke, during hot weather, if people don't know how to take care of and protect their health, they are very susceptible to heatstroke.

Heatstroke, also known as heat shock, is a condition characterized by severe hyperthermia (>40°C) accompanied by dysfunction of organs such as the nervous, circulatory, and respiratory systems, caused by the effects of hot weather and/or excessive physical activity.

Heatstroke is caused by prolonged exposure to high temperatures combined with dehydration. In urban areas, heatstroke is even more likely during prolonged heatwaves due to lack of wind, poor air quality, and burning asphalt.

Heatstroke often occurs at midday during intense heat and high levels of ultraviolet radiation, combined with working in hot, humid conditions with poor air circulation.

Mild initial symptoms include: rapid heartbeat, rapid breathing, flushed skin, possibly sweating, accompanied by dizziness, lightheadedness, headache, and nausea.

More severe symptoms may occur if not treated promptly: hypotension, neurological dysfunction including altered consciousness, agitation, delirium, confusion, seizures, and coma.

When body temperature rises too high, it can cause severe electrolyte imbalances, disrupt homeostasis, and potentially lead to bleeding (conjunctival hemorrhage, hematuria, etc.) due to severe coagulation disorders. In more severe cases, it can cause multiple organ failure, resulting in death.

The hour following severe heatstroke is known as the "golden hour" for emergency treatment. Therefore, when providing emergency care for heatstroke, utmost attention must be paid to initial first aid at the scene.

How can we prevent it?

To prevent strokes, doctors recommend that elderly people avoid outdoor activities between 10 am and 4 pm on hot days. In the morning, they should engage in light activities such as Tai Chi, yoga, or cycling, and avoid strenuous exercise.

Elderly people often exercise in the afternoon. However, on extremely hot days with high temperatures, it's not advisable to exercise, because although the temperature drops in the afternoon, the outdoor temperature remains very high.

In addition, elderly people need to pay special attention to their care regimen. They should eat and drink easily digestible liquids and soft foods, plenty of green vegetables and fruits; and make an effort to drink plenty of water regularly to compensate for the body's water deficiency. In particular, they should not wait until they are thirsty to drink; they should drink at least 2 liters of water per day.

During hot weather, high humidity and dehydration through breathing and sweating can disrupt blood clotting and cause strokes.

Patients with multiple underlying health conditions need to take their medication regularly. Because of the hot weather, elderly people often feel tired and uncomfortable, so skipping medication can be very dangerous, especially for those with chronic diseases such as diabetes, hypertension, and cardiovascular disease.

During hot weather, families use air conditioners continuously. However, families with elderly people or young children should set the temperature between 27 and 29 degrees Celsius and add a fan or humidifier. During cooler periods, avoid overusing air conditioners and open windows to ventilate the room.

Elderly people should avoid sudden changes in environment, such as going from an air-conditioned room to the hot sun; they need a buffer space to avoid thermal shock. In addition, to avoid serious complications, they should seek immediate medical attention for diagnosis and treatment if any unusual symptoms appear.

In cases of heatstroke, according to guidelines, when encountering someone suffering from heatstroke, immediately take the following steps: Move the patient to a cool, well-ventilated place (shade, in a cool vehicle or house, etc.) and call for help, especially emergency medical assistance.

Clear the airway, perform artificial respiration and chest compressions if the patient is unconscious and has no pulse. Immediately apply cooling measures to lower body temperature. Measure body temperature (if a thermometer is available).

Remove the patient's clothing and apply warm water to their body, then use a fan to increase evaporation (the patient should lie on their side or be supported with their hand on their knee so that the skin surface can receive as much airflow as possible).

Apply cold compresses or ice packs to the armpits, groin, and neck. Give plenty of water or electrolyte solution if the patient is conscious and able to drink.

Transporting patients in air-conditioned vehicles or with windows open ensures that the patient's temperature remains cool throughout the journey.

Some recommended measures to prevent heatstroke include limiting outdoor activities during hot weather: The period from 11 am to 3 pm is when the intensity of the sun is highest, so outdoor work should be avoided.

If you have to go outside, you need to cover your body by wearing loose, light-colored clothing, a wide-brimmed hat, and using sunscreen.

Drink plenty of fluids: To avoid dehydration, everyone should drink at least 8 glasses of fluids (water, fruit juice, or vegetable juice) each day. Since heat-related disorders can also result from salt loss, electrolyte-rich sports drinks can be helpful on hot days.

Avoid showering with cold water after being in hot weather: After exercising or being outdoors in the sun, your heart rate is still high, your body temperature is high, and your pores are dilated. Showering immediately will prevent blood from circulating to vital parts of the body, leading to localized ischemia of the heart and brain.

You should rest to allow your body temperature to cool down, drink plenty of water to replenish fluids, and let the sweat dry. After showering, you shouldn't immediately go into an air-conditioned room with the temperature set too low.