Dr. Marla Shapiro: Why heat waves are so dangerous
Published Tuesday, July 17, 2012 8:46AM EDT
Last Updated Tuesday, August 14, 2012 7:42AM EDT
As Canadians who freeze much of the year, it seems unreasonable to complain about the heat. But with this extreme heat come serious health hazards.
So what exactly is the issue? As Health Canada explains, in the hot weather -- and even more so if you exercise -- our body heats up. We lose our heat by sweating and by contact with cooler air. With the high humidity, our body is even less efficient at sweating than it is with the heat alone. Bad combo -- high heat AND humidity!
Did you know that the heat wave in Europe in 2003 killed 70,000 people and the heat wave in Chicago in 1995 killed 700 people?
So who is at risk? Well, we all are, but the highest risk groups are older adults, infants and children, those with pre-existing conditions such as asthma, COPD, heart conditions and those who cannot understand how to care for themselves.
Heat can lead to the spectrum of heat stroke: exhaustion and fainting and even swelling related to heat. You can get heat rashes and heat cramps.
Symptoms such as dizziness and fainting, nausea and vomiting, headache, fast heart beat, difficulty breathing and being thirst are warning signs. If you are urinating less that too is worrisome.
Older people and people with chronic medical conditions may not sense that they are getting into trouble and they are more prone to heat stress. Chronic medical conditions can change the normal body response to heat. Prescription medications can slow down the body's ability to self regulate to heat. They can perspire less, for example.
Examples of medications that can put one more at risk for heat related illness include: psychotropic drugs, drugs that can affect function or behaviour; Parkinson's medication, which can inhibit sweating; tranquilizers; and so-called water pills or diuretics because they can dehydrate the body and interrupt the balance of electrolytes in our body.
When our body begins to shut down because of relentless high heat and humidity, our brain gets impacted, starting with confusion and ultimately loss of consciousness. The central nervous system and our circulatory systems will shut down in short order as well. One can even see kidney problems.
A great checklist of what to do during a heat wave can be found at the Red Cross website at www.redcross.org.
BEAT THE HEAT
- Prepare for the heat
- Watch for symptoms
- Stay hydrated- 2-4 glasses hourly
- Stay cool
- Take a break from the heat
- Avoid sun exposure
- Eat small meals more often
- Wear loose fitting clothing
- Check on friends and family
WHO IS AT RISK
- Fever and dehydration
- Heart Disease
- Mental illness
- Poor circulation and heart conditions
- Prescription drug use
- Alcohol use