Month: May 2009

Heat Stress

by National Peo National Peo No Comments

The days of summer are upon us here in Arizona and the rest of the country is only a couple weeks in back of us for the most part. Playing and doing yard work outside and for many working outside in the heat on a daily basis is just part of the job.

Unfortunately the majority of people don’t think about heat stress or dehydration until it is too late and they end up in the back of an ambulance on the way to the emergency room. Heat stress and dehydration sneak up on you gradually and can have devastating affects on the body which in the worse case scenario can lead to permanent organ damage or even death.

The body has to cope with two sources of heat, the first one being metabolic heat (the process of living and moving) and environmental heat. Also, the body only has two means of cooling, the primary is through radiation of body heat to the atmosphere and the second is evaporation through sweating.

When the body core temperature starts to rise due to activity, the brain tells the heart to beat faster and send all excess blood to the skin to get rid of the heat. When radiation can not dissipate heat fast enough, the brain tells the sweat glands to produce sweat for evaporation. As long as the ambient temperature is at or below 98.6 degrees with relatively low humidity, the body is able to dissipate excess heat. However, when the ambient temperature is above the normal body temperature of 96.8 degrees the bodies cooling system becomes less efficient. The higher the ambient temperature goes, the less efficient the cooling system becomes and the body starts to absorb heat from the environment.

There are several risk factors that increase your possibility of heat related stress and they are:

  • Age – infants, young children and the elderly have trouble dealing with heat.
  • People over the age of forty.
  • Obesity and overweight people have trouble with heat.
  • People in poor physical condition have trouble with heat.
  • People with coronary problems have trouble with the heat.
  • Use of illegal drugs affects how the body cools and deals with heat.
  • Use of certain prescription drugs may have the same effects as illegal drugs.
  • Use of alcohol and caffeinated drinks accelerates dehydration in the heat.
  • High blood pressure affects how the body deals with heat.
  • People with liver or kidney problems have trouble with the heat.
  • Respiratory problems affect how the body deals with the heat and cooling.
  • Diabetes reduces the ability of the body to deal with the heat.
  • If you are already sick with a fever.
  • If you are sleep deprived the body can not deal with the heat properly.
  • If you have a poor diet or are on a low salt diet the body has trouble with the heat.
  • If you have already suffered heat cramps, heat exhaustion or heat stroke, you are more prone to suffer it again, at a lower temperature, with faster onset and more severe symptoms.

There are five different types of heat related stress and almost every one has experienced at least one of the least dangerous.

Transient Heat – Occurs when you travel from a cool environment (Canada) to Phoenix, Arizona in the middle of the summer. It will take the body approximately seven days to acclimate to the new environment as long as the body is properly hydrated.

Heat Rash (Prickly Heat) – Occurs when the sweat glands become plugged and can not sweat. The sweat glands become inflamed, bumps form, the skin turns red and itches like poison ivy.

Keep the affected area(s) clean, dry and use a medicated powder until the rash clears up.

Heat Cramps – Occurs when the big muscles of the legs, arms and shoulders start to become dehydrated and a loss of electrolytes and salts from the body takes place in the body. The cramps can occur during or several hours after exertion.

If you are still working or playing, stop and rest in a cool area, drink cool water or a sport drink to replenish liquids, electrolytes and salts in the body.

Heat Exhaustion (Serious) – Occurs when the body is dehydrated and is absorbing heat. The symptoms are fatigue, weakness, dizziness, faint, nausea, headache, cool moist skin, normal or slightly elevated temperature, rapid pulse, pale or flushed skin.

Move the person to a cool area to rest, sip cool water or sport drink, sponge down, use hose or shower to dissipate heat and cool the body. The person needs to medical attention as soon as possible.

Heat Stroke (Life Threatening) – Occurs when the body thermostat stops working and the brain shuts down sweating to conserve the little bit of water remaining and the body starts to absorb more environmental heat. Symptoms include hot dry skin; skin is flushed, red or bluish, confusion, rapid pulse, convulsions, elevated core temperature (105 degrees or more), and unconsciousness. This may be fatal or cause permanent damage to the brain, heart, lungs, liver, kidneys or muscles.

This is a medical emergency, dial 911 immediately, time is critical and every minute counts in this situation. Remove the person to a cool location, remove clothing, sponge or hose them down or immerse in water. Do not give any fluids if the person is conscious because the person will not keep it down.

Heat related illness is preventable through training, monitoring the work environment and making sure the employees stay hydrated and take frequent short breaks to help cool down.

In parts of the country where temperatures very seldom reach the high 90’s and a heat wave hits with temperatures in excess of 100 or 105 degrees, work and play activity should be curtailed until the temperature drops.

In Arizona approximately 29 people die every year due to heat stroke and approximately 4 of those are work related.

HEAT KILLS.