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The Heat is On

When the dog days of August get too hot to handle, there's no need to get all steamed up.

Hot Weather Tips

Taking preventive measures to avoid heat stress can help you remain light-hearted when temperatures soar.

  • Stay in the coolest environment available, preferably air-conditioned. If you are using a fan, keep windows open that are in shaded areas if possible. If the temperature is above 90 and no air conditioning is available, spend time in air-conditioned public places like the mall, movies or library.
  • Drink plenty of cool water. Avoid alcohol, which can impact your ability to sweat properly, and caffeine, which is a natural diuretic. For congestive heart failure patients, there's a delicate balance between draining excess fluid and avoiding dehydration - these individuals should watch their weight to ensure that they are not gaining or losing fluid.
  • Eat light, easily digested food. Avoid hot or heavy foods that will increase your core temperature during digestion.
  • Dress in light-colored, loose-fitting, breathable clothing so sweat can evaporate. In the hot sun, cover up with a hat and sunscreen.
  • Limit outdoor activity during midday when temperatures are highest. Try to rest often in shady areas so that your body's thermostat will have a chance to recover.
  • Exercise in controlled temperature settings. You can stay active during the hottest heat wave by visiting an indoor gym or pool, walking in shopping mall, taking a fitness class or even ice skating at an indoor rink!

Why Heat Can Be Hazardous

"Engaging in outdoor activities in hot and humid conditions can be hard on your heart," said Dr. Airley E. Fish, a cardiologist who practices at the CVI in Boston, Chelsea and Needham. "The heart works to circulate blood and oxygen to muscles while the body attempts to cool itself by sweating. Sweating too much decreases blood volume and makes your heart work harder to circulate blood. This state of dehydration can raise your body temperature and cause heat-related injuries."

Who is at risk for heat stroke?

Some people have a greater than average risk for heat stroke. They include:

  • People with heart disease or high blood pressure or those who take certain medications may be more vulnerable to extreme heat.
  • People over age 65, whose bodies do not control temperature as well as a younger individual.
  • People who are overweight, since their bodies may hold more heat than someone with normal body weight.
  • Infants and children aged 4 or under, who can dehydrate quickly because of their small size.

Trouble Signs and Solutions

In extreme temperatures, people can experience heat cramps, heat exhaustion or heat stroke. Here are the systems and remedies for each of these heat-related ailments.

Heat cramps

Heat cramps are muscle cramps usually experienced in the stomach, arms or legs during heavy activity.


It is best for the person experiencing heat cramps is to sit quietly in a cool place and drink sips of water, clear juice, or a sports drink. Applying pressure or gentle massage can help relieve the cramps. If the cramping continues after an hour, seek medical attention.

Heat exhaustion

Heat exhaustion can occur from excess exposure to or activity in extreme heat.


Symptoms for heat exhaustion can include:

  • Heavy sweating
  • Breathlessness
  • Fast but weak pulse
  • Paleness
  • Nausea or vomiting
  • Dizziness
  • Tiredness
  • Headache
  • Weakness
  • Fainting
  • Muscle cramps


Cool the person experiencing heat exhaustion by placing them in an air-conditioned room or shaded area. They should remove excess clothing, sip cool water, and rest. Applying cool, wet cloth or towels on the skin or taking a cool shower or bath can help. If the symptoms are severe, or if the person has heart disease or high blood pressure, medical help should be called right away.

Heat stroke

Heat stroke is a life-threatening condition that requires immediate medical attention. The body can no longer cool down through sweating, body temperature can quickly rise to 106°F or higher and damage to major organs or even death can occur.


Symptoms for heat stroke include:

  • Hot dry skin
  • Fever higher than 102°F
  • Quick pulse
  • Headache
  • Nausea or vomiting
  • Confusion or unconsciousness


While awaiting help, cool the person experiencing heat stroke in an air-conditioned room, in the shade or by fanning. Apply cool water with wet cloths, a bath or shower or even light spray from a garden hose. The person's muscles may begin to twitch - if this occurs, do not place anything in the person's mouth and do not give them anything to drink. If vomiting occurs, place the person on their side to keep their airway open. Continue cooling efforts until body temperature drops to 102°F. If emergency medical personnel are delayed, call the hospital emergency room for further instructions.

Keep Your Cool

Signs of heat stress can be avoided by using common sense during a hot spell. Don't forget old fashioned remedies like eating frozen fruit or popsicles, keeping a water spritzer or outdoor sprinkler handy or finding a spot to sit in a cool basement. When it's hot, hot, hot - make sure you're not!


Posted August 2010

Contact Information

CardioVascular Institute at
Beth Israel Deaconess Medical Center
330 Brookline Avenue
Boston, MA 02215