This summer has been characterized by very high temperatures and high humidity. As a result, heat illness will affect many people this summer. Heat illness occurs when body temperature exceeds the individual's ability to dissipate that heat. The clinical characteristics of heat illness are commonly seen when the body temperature approaches 104 degrees Fahrenheit and when humidity is greater than 70%. Once the humidity is high, sweating becomes less effective at dissipating body heat and the core body temperature begins to rise.
Who's at Risk? What are the Risk Factors?
Heat illness is characterized by loss of sweating, confusion leading to coma, fast pulse, low blood pressure, heart failure and kidney failure. Patients with heat illness will not be able to notice the change so it's important that family members be alert for changes when the mercury begins to rise, especially in the very young and the very old who are most susceptible to heat illness.
Infants and the very young have a high surface area to mass ratio and will absorb heat from the environment more readily. The young also have no way to remove themselves from warm environments. If they are left unattended in a car or enclosed area without cooling, their body temperatures can rise very quickly. Teenage athletes are very prone to heat illness in the summer months when beginning training schedules for such activities as soccer and football.
The elderly frequently have heart disease, take medication that can lead to dehydration, and may live in enclosed environments that are not cooled. Many may have muscular, neurologic or psychiatric diseases that make them unable to remove themselves from those environments. There are many psychiatric drugs that predispose to heat illness. Obesity and alcohol abuse are very frequent risk factors for heat illness.
How do I Prevent Heat Illness?
If you know of someone with these risk factors for heat illness, you must take special precautions. Never leave children (or pets) in a closed automobile or closed space in a heated environment for any period of time. This is one of the leading causes of death in children (and pets) in the summertime. Check on the elderly frequently and if possible, make sure they have access to cooling measures. A mist bottle with a fan can be very effective. Avoid diuretics and alcohol in older individuals who do not have access to cooling. Take them to cooling shelters if necessary. Provide them with plenty of liquids and ice to stay cool and well hydrated. Open windows and install fans if they do not have cooling within their living areas. This can be a problem in inner cities because of the potential for crime. The elderly frequently remain in closed heated environments for safety and security reasons, but this will risk heat illness.
What Happens to the Kidneys When Someone Has Heat Illness?
Body temperatures in excess of 104 degrees Fahrenheit will cause significant problems for the kidneys. Dehydration will lead to low blood pressure and decreased kidney function. Many metabolic systems start to shut down in response to heat illness and a decline in kidney function is part of that abnormality in metabolic systems. There is breakdown of muscle tissue that results in kidney failure. Finally, heart failure and shock can lead to kidney failure during episodes of severe heat stroke. Avoid the use of non-steroidal anti-inflammatory drugs (NSAID's) such as Motrin, Ibuprofen, Advil, or Aleve during exposure to heated environments as this can lead to acute kidney failure.
What if I Suspect Heat Illness?
If you have someone who is warm and confused or delirious, not making any urine and breathing rapidly, you must get these folks to a cooler environment. You should activate emergency services to have them transported to an emergency facility. If you have access to fan, ice or cooling mist, you should place the patient in a cooler environment. If they are unconscious or poorly responsive, do not offer them oral liquids for fear of inducing aspiration and pneumonia. External cooling such as mists plus fan, ice packs to the head and neck, removing clothing and applying cool compresses can all be effective. An ice bath may occasionally be used in the most extreme circumstance, but getting the patient to emergency services is the most important. It is also important to protect the patient's airway so that they do not aspirate or stop breathing. It is best to call emergency services to assist with someone having difficulty with breathing.