Heat. It’s on my mind today. It’s a hot topic on everyone’s minds. We are all longing for a cool change. Some are even dreaming of the long term, when summer will give way to the milder days of autumn.
I learned a lot about heat when I worked in a nursery that grew aquatic plants. Quite a few men were unable to take the heat, and quit. I soldiered on, glad to have an income. I worked in the hothouse section, which was a number of tunnels fully enclosed by plastic. Some of the tunnels grew plants in large tanks of water. In others, the plants were grown in boxes of worm castings on shelves. Either way, it was hot. There was no air flow, and the humidity was maintained at dripping point to keep the plants from drying out. On really hot days, sometimes I would walk into a hothouse and my eyeballs would fog up because they were cooler than the air inside the hothouse. Heat headaches were common, and I had heatstroke twice. It wasn’t good. But all this heat got me wondering about what overheating does to the human body. It’s a hot topic!
SYMPTOMS OF HEAT EXHAUSTION
- Some of the early symptoms of heat exhaustion include:
- headaches
- nausea
- goose bumps
- shivering
- tingling feelings in the skin
- dizziness
- rapid heartbeat
- lethargy or sudden fatigue
- Muscle cramps
HEATSTROKE
- Heatstroke is a more serious illness, and is often diagnosed by one or two classic symptoms: a body temperature over 104 degrees Fahrenheit (40 degrees Celsius), and some kind of cognitive impairment – confusion, lethargy, or agitation. It is often accompanied by nausea, vomiting, dizziness, severe headache, rapid heartbeat and breathing, muscle weakness or cramps, lack of sweating, and in severe cases, seizures.
- Heatstroke causes mental impairment because nerve cells are especially vulnerable to heat stress. The brain has more nerve cells than any other part of the body, and is one of the first places to experience heat stress.
- Heatstroke is a serious illness and can cause shock, coma, kidney and brain damage, and even death.
WHAT TO DO FOR HEAT EXHAUSTION
- If you think you or someone else might be suffering from heat exhaustion, it’s important to act quickly. Left untreated, heat exhaustion can progress to heatstroke.
- Get out of the heat, if possible into an air conditioned room. If that’s not possible, seek shade.
- Remove tight, restrictive or excess clothing.
- Drink plenty of fluids – water is best. Avoid alcohol or other sugary drinks, as they can make heat exhaustion worse.
- If possible, get into a cool bath or shower, or place a cool wet cloth over your skin.
- If your symptoms have not eased in thirty minutes, you should seek medical attention.
WHAT TO DO FOR HEATSTROKE
If you think someone has heatstroke:
- Seek medical help right away.
- Get the victim into air conditioning or shade
- Remove restrictive or excess clothing
- Place a wet cloth on the skin. If you can fan the person with a book or some other object, it will create a breeze on the wet cloth, aiding it in cooling the victim.
- Wrap an ice pack in a cloth and place it under the armpits, on the groin or on the neck and back. These are areas of high blood flow, and as the blood passes the ice pack, it will help to cool the body down.
- If possible, get the victim into a cool shower or bath while waiting for help to arrive.
- Offer cool fluids to drink, but only if the victim is awake and able to drink normally.
SYMPTOMS THAT REQUIRE URGENT MEDICAL ATTENTION
Seek help urgently if you notice someone has the following symptoms:
- Mental confusion, irritability, delirium or stupor
- Seizures or loss of consciousness
- Skin that looks red (grey in the later stages) and feels hot and dry, but not sweaty,
- Difficulty breathing
- Shortness of breath or shallow, rapid breathing
- Frequent vomiting
- Rapid heartbeat
- Body temperature over 104 degrees (F) or 40 degrees (C)
HOT TOPIC: DID YOU KNOW?
- Seniors and babies are most at risk of heat related illness. If you have elderly neighbours or family members, keep an eye on them during hot weather to make sure they are ok. Seniors are more at risk because the body’s heat regulating mechanisms work less efficiently with age.
- Sweating a lot can lead to an imbalance of electrolytes in the body (ie magnesium, potassium, sodium and calcium), making the body vulnerable to a heat related illness.
- Overweight people are more at risk, as extra layers of body fat tend to retain heat.
- Heat related illness is more likely to occur in conditions of high humidity. This is because high levels of humidity prevent the body from cooling itself when sweat fails to evaporate from the skin.
- Strenuous work or exercise in hot weather increases the risk. Athletes and outdoor workers are in a higher risk category for heat related illness.
- Dehydration or insufficient fluid intake causes many cases of heat related illness. Always have water handy, and be aware of how much you are drinking on a hot day.
- Some medications, such as diuretics, antihistimines, some blood pressure and heart medications, laxatives, seizure medication, and some illegal drugs, such as amphetamines, may increase the risk of heat related illness. If you are unsure about a medication you’re taking, check with your doctor, and take it easy in the heat!
- People with heart disease and diabetes are in a higher risk category for heat related illness.
- A recent dehydrating illness, such as diarrhoea or vomiting, leads to a higher risk of heat exhaustion or heatstroke.
- Some people are born with impaired sweat gland function, leading to a greater risk of overheating.
- After a heat related illness, you will be sensitive to the heat for about a week. Take care not to overdo it.
- Professional treatment of heatstroke involves controlled, gradual cooling of the patient, intravenous or oral fluids to treat dehydration and replace electrolytes, and medication to control seizures if they occur.
- As the body’s core temperature increases, blood flow to the skin increases, which enables it to produce more sweat. However, this places a strain on the heart, of concern for those with poor cardiovascular health. As the sweat output increases, dehydration sets in, causing further strain on the heart.
PLAY IT SAFE IN THE HEAT
Commonsense and awareness of your limits go a long way towards the prevention of heat related illness. Here are a few simple tips:
- If you have a choice, plan your work and activities for early in the day or later in the afternoon. Avoid being outside in the middle of the day, if possible.
- Be aware that your need for water is going to be a lot greater than it is at milder temperatures. In extreme heat, take extra water and make sure you drink it regularly. Little and often is better than infrequent large amounts.
- Wear light coloured, loose fitting clothing
- It takes time for the body to acclimatize to heat (up to three weeks). During periods of acclimatization, take regular breaks in a cool place to allow your body time to adjust. Gradually increase the time you spend in the heat until you adjust to it.
- Don’t get caught out – monitor forecast conditions and plan accordingly.
- Use sunscreen, a hat, and an umbrella if appropriate.
- Avoid strenuous activity in the middle of the day – athletes and people playing sport need to be especially careful, particularly when coming from a place with a cooler climate.
Heat. A hot topic in an Australian summer! But for most people, it can be managed safely and effectively by following a common sense approach, being aware of the dangers, and alert for symptoms. And before we know it, autumn will be here. Goodbye heat!