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Signs of trouble to watch out for in extreme heat


With the heat dome over Ottawa bringing another day of extreme heat to the capital, there are signs to watch out for in yourself or others that could indicate serious medical problems.

The humidity, especially, can create risks because it inhibits our bodies' natural cooling mechanisms.

There are three major risks in extreme heat events: dehydration, heat exhaustion, and heat stroke.

Ottawa Medical Officer of Health Dr. Vera Etches says one of the primary pieces of advice — drink lots of water — is important because of how our bodies work.

"Your body is trying to keep cool by sweating and you lose fluids and you lose salt and dehydration is one thing that can happen," she says.

Signs of dehydration include:

  • Thirst
  • Dry skin
  • Fatigue
  • Light headedness
  • Confusion
  • Dry mouth
  • Increased heart rate
  • Increased breathing rate
  • Less frequent urination

"Moving along the severity of symptoms, you can get into heat exhaustion," Etches says. "You might start to have headaches and feel dizzy. These things can be treated by getting someone to a cool place."

Other signs of heat exhaustion include:

  • Blurred vision
  • Nausea or upset stomach
  • Vomiting
  • Sluggishness or fatigue
  • Thirst
  • Profuse sweating
  • Moderate increase in body temperature

Ottawa paramedics treated six people for heat-related illnesses during the first two days of the heat wave. Two men were treated for heat stroke on Monday after exercising outside, while two people were treated for heat stroke on Tuesday after spending "several hours outside."

A paramedic spokesperson says a man was treated for mild heat exhaustion while at work on Monday.

Etches says finding shade or even making it yourself with an umbrella or parasol can help, if you can't get somewhere cool.

"If people stay in a hot environment and aren't able to keep cool, you can get to the dangerous level of heat stroke," Etches says. "It does need immediate emergency attention. That's when your body's not able to cool and you might even get confusion, disorientation, and hallucinations."

Other signs of heat stroke include:

  • Dizziness
  • Disorientation, agitation or confusion
  • Sluggishness or fatigue
  • Seizures
  • Hot dry skin
  • Increased body (inner) temperature
  • Loss of consciousness
  • Rapid heart beat

Heat stroke can be fatal. If you or someone you know is experiencing heat stroke, call 9-1-1 immediately and try to get to a cool, dry place as soon as possible.

"You might not be someone who thinks it could apply to you, but if you're exerting yourself outside, if you're pregnant or taking certain medications, it can put you at higher risk," she says. "I'm asking everyone to pay more attention and be cautious."

Older adults and infants are at greater risk, as well as people with chronic illnesses.

The heat warning for Ottawa calls for daytime highs of 30 to 35 C with humidex values of 40 to 45, with little relief at night, as lows are expected to be 18 to 23 C with humidex values of 26 to 30. The daytime high is expected to be below 30 on Friday, with cooler temperatures and a possibility of rain the forecast for the weekend.

WIth files from CTV News Ottawa's Josh Pringle Top Stories


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