Don't fry: 3 stages of heat stroke you need to know

This weekend, a dangerous heat wave will blanket roughly two-thirds of the nation, with officials from Wisconsin to Boston declaring heat emergencies. On Saturday, more than 100 local heat records are expected to be broken, as temperatures remain high even at night, according to the National Weather Service.

So, it's critical to stay cool. That's especially true for seniors, small children, and people who actively participate in outdoor activities, such as construction workers and athletes.

Feeling dizzy or sluggish outside on a scorching day could be your body signaling a more serious condition.

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Concerns over health as heat wave hits much of U.S.

02:11

Don't ignore these three stages of heat-related illnesses:

1. Heat cramps

The first stage is heat cramps. Severe muscle spasms occur as a result of salt and water loss following exertion, most often in the hands, calves, and feet. Muscle spasms can spontaneously stop on their own, but lingering symptoms of soreness often persist for 24-48 hours.

2. Heat exhaustion

Next is actual heat exhaustion. More than just feeling fatigued, heat exhaustion is a serious condition caused by exposure to high temperatures, humidity, and strenuous physical activity.

It occurs when the body’s core temperature increases to 101-104 degrees Fahrenheit.

Symptoms include:

• headache
• low-grade fever
• nausea or vomiting
• increased thirst
• generalized weakness
• muscle ache or cramping

Feeling agitated and anxious are common and some people may even faint as blood pressure tries to compensate, but ultimately lowers. This deregulation by heat exhaustion can lead to stoke or other a life threatening conditions, if left untreated.

3. Heat stroke

The final stage is heat stroke and is considered a medical emergency — get help fast. This potentially fatal condition is a result of prolonged heat exposure or physical exertion. A heat stroke is characterized when the body’s core temperature reaches 104 degrees Fahrenheit or higher.

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Symptoms include:

• confusion due to lack of blood flow to the brain
• reddened dry skin
• lack of sweat
• organ failure
• convulsions or seizure.

Fortunately, these conditions are preventable with some simple preparation and paying close attention to your body. Some safety tips include:

• Frequent hydration: drink a cup of water every hour.
• Avoiding alcohol use — alcohol and even caffeine can actually dehydrate the body.
• Monitoring the temperature — check the outside temp throughout the day.
• Limit strenuous activity — particularly during peak hours of the day 11 a.m. - 4 p.m.

Other ways to monitor how your body is doing when in the heat is to check the color of your urine — dark yellow urine means time to hydrate. One would expect to sweat a lot if out in the sun, but if there is decreased sweating it’s another sign of dehydration so limit any strenuous activity.

If someone else shows danger signs of heat exhaustion:

• Move the person out of the heat and place them in a cool environment.
• Place cold water on the individual.
• Have the person drink cool water or a non-alcoholic, non-caffeinated beverage.
• Remove tight or heavy clothing.
• Take the individual’s temperature if a thermometer is readily available.
• Call for assistance if needed and monitor the individual closely.

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