Extreme Heat Takes a Toll on Our Health and Life

A woman drinking water on a warm day. (iStockphoto/Thinkstock)
A woman drinking water on a warm day. (iStockphoto/Thinkstock)

There are two kinds of people. People who like heat in moderation and those who like heat in extreme. Then there is a third group of people who like extreme cold weather. Nature took care of this group by turning them into polar bears.

I am a person who likes heat in moderation. My friends say I should be the last person on earth (that is little far fetched, isn’t it?) to complain about heat.

I was born and raised in Musoma and Mwanza on Lake Victoria. I would call the weather in those two places is not bad. Nice and warm all year round. Then I went to a boarding school in Dar-es-salaam, on the shores of Indian Ocean. Wow, the weather is hot and humid. White shorts and shirts were the norm on weekends. On school days, khaki shorts and white shirt.

Those were the days. I was young and healthy. Heat wasn’t a big deal. I didn’t have hairy legs or varicose veins sticking out of my ugly legs. I didn’t have all the scars from childhood injuries showing off from my multi coloured legs. Wearing shorts was cool.

Now things are different. Once you get to male or female menopause, your tolerance for heat is not the same. Your kidneys start to pack-in if you do not drink enough water. And among the aging population, extreme heat causes a substantial number of deaths.

For example, the European heatwave of 2003 resulted in more than 70,000 deaths, About 30 per cent of which were attributed to heatstroke, hyperthermia or dehydration. Canadians too die of extreme heat. Reports indicate that extreme heat recently contributed to 106 deaths in Montréal, Quebec, and 156 deaths in Vancouver, British Columbia.

People who have chronic physical conditions (cardiovascular, pulmonary, renal and neurologic disease, diabetes and obesity) and those with mental illness are vulnerable to extreme heat. Older people, children and people who are very physically active in the heat are also at higher risk for heat-related illness.

Common drugs such as antipsychotic agents, antidepressant medications (e.g., selective serotonin reuptake inhibitors, lithium), diuretic agents, antihistamines, anticholinergic agents and anti-Parkinson agents can increase risk by interfering with thermoregulatory mechanisms, says an article in the Canadian Medical Association Journal (CMAJ July 10, 2012).

What is heat exhaustion?

Heat exhaustion is the most common heat illness, says the CMAJ article. Although the patient may have hot skin and be flushed and sweating, his or her core temperature is below 40°C.

What is heatstroke?

In heatstroke, the core temperature is above 40°C, the patient’s mental status may change, and he or she may become incoherent or unconscious, says the article. In classic heatstroke, the skin is usually hot, red and dry. In exertional heatstroke, there is profuse sweating after high-intensity physical activity.

Heatstroke is a medical emergency. It can progress rapidly to multiorgan dysfunction and death. Treatment must be immediate and consists of rapid cooling (evaporative cooling for classic heatstroke; ice-water baths for young adults and people with exertional heat stroke). Careful attention should be paid to the patient’s hydration and electrolyte balance to restore blood pressure and tissue perfusion.

Death from heat exposure is preventable by increasing fluid intake and reducing activity levels during hot weather. Cool or air-conditioned environments for people most vulnerable to heat also helps. Some communities have heat alert and response systems that include issuing public health messages, opening cooling centres and extending hours for public swimming pools.

Enjoy the summer but be careful.

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Dehydration Can Be A Serious Problem

It is only mid-April and I can feel the heat. I feel dry and thirsty most days. My urine is dark and concentrated. That means I am losing more water than I take in. Most of the water I am losing is during exercise and walking 18 holes on a golf course on a hot day.

Where am losing my water from?

A healthy individual loses water from exposure to high environmental temperature or from strenuous exercise. If you are not well then you may lose water because you are on a diuretic, you may have diarrhea or fever and you may be a diabetic or have kidney problems.

Earliest symptoms of dehydration are thirst and decreased output of concentrated urine. Thirst is not always a reliable indicator of dehydration. Urinary output and concentration is more reliable. Dark coloured or amber urine indicates our body needs more water.

Skin has an important role to play in water and electrolyte balance. Skin is the largest organ of our body and protects us from environment. Skin is constantly exposed to sun, wind and other injuries.

Skin has a capacity to excrete fluid and electrolytes. It plays an important role in maintaining body temperature. When a person feels hot the blood vessels in the skin dilate and sweat secretion increases. The body loses heat by radiation from the large amount of blood circulating through the dilated blood vessels in the skin and by evaporation of sweat.

Sweat glands are found in almost every part of the skin. They normally release a little fluid all the time, and as this fluid evaporates, our body cools off. If we need to cool off then these glands can get stimulated to be more active. They secrete even more fluid and help us cool off more thanks to skin temperature nerve endings.

Oil glands (sebaceous glands) produce oil secretion known as sebum. The sebum spreads on the skin. It prevents excess water loss, lubricates and softens the skin and hair.

Mild dehydration can cause symptoms such as weakness, dizziness and fatigue. Severe dehydration is a life-threatening medical emergency. Mild to moderate dehydration can be corrected by consuming more fluids. Severe cases of dehydration require immediate medical treatment.

To prevent dehydration one must consume plenty of fluids and foods high in water. It is best to start this the day before strenuous exercise. Producing lots of clear, dilute urine is a good indication that you’re well hydrated. Drink two glasses of water before your exercise. During the physical activity, drink more fluids at regular intervals, and continue drinking water or other fluids after the physical activity is done.

As we get into warmer days, a bottle of water should become your good friend. Again, remember, don’t wait to feel thirsty. Prevent dehydration before it gets to you.

Start reading the preview of my book A Doctor's Journey for free on Amazon. Available on Kindle for $2.99!

Dehydration

It is early May and I can feel the heat. I feel dry and thirsty most days. My urine is dark and concentrated. That means I am losing more water than I take in. Most of the water I am losing is during exercise and walking 18 holes on a golf course on a hot day.

Where am losing my water from?

A healthy individual loses water from exposure to high environmental temperature or from strenuous exercise. If you are not well then you may lose water because you are on a diuretic, you may have diarrhea or fever and you may be a diabetic or have kidney problems.

Earliest symptoms of dehydration are thirst and decreased output of concentrated urine. Thirst is not always a reliable indicator of dehydration. Urinary output and concentration is more reliable. Dark coluored or amber urine indicates our body needs more water.

Skin has an important role to play in water and electrolyte balance. Skin is the largest organ of our body and protects us from environment. Skin is constantly exposed to sun, wind and other injuries.

Skin has a capacity to excrete fluid and electrolytes. It plays an important role in maintaining body temperature. When a person feels hot the blood vessels in the skin dilate and sweat secretion increases. The body loses heat by radiation from the large amount of blood circulating through the dilated blood vessels in the skin and by evaporation of sweat.

Sweat glands are found in almost every part of the skin. They normally release a little fluid all the time, and as this fluid evaporates, our body cools off. If we need to cool off then these glands can get stimulated to be more active. They secrete even more fluid and help us cool off more thanks to skin temperature nerve endings.

Oil glands (sebaceous glands) produce oil secretion known as sebum. The sebum spreads on the skin. It prevents excess water loss, lubricates and softens the skin and hair.

Mild dehydration can cause symptoms such as weakness, dizziness and fatigue. Severe dehydration is a life-threatening medical emergency. Mild to moderate dehydration can be corrected by consuming more fluids. Severe cases of dehydration require immediate medical treatment.

To prevent dehydration one must consume plenty of fluids and foods high in water. It is best to start this the day before strenuous exercise. Producing lots of clear, dilute urine is a good indication that you’re well hydrated. Drink two glasses of water before your exercise. During the physical activity, drink more fluids at regular intervals, and continue drinking water or other fluids after the physical activity is done.

As we get into warmer days, a bottle of water should become your good friend. Again, remember, don’t wait to feel thirsty. Prevent dehydration before it gets to you.

Start reading the preview of my book A Doctor's Journey for free on Amazon. Available on Kindle for $2.99!