During these hot summer days, you need to be very careful in the heat. Rising temperatures and humidity combined with any risk factors, such as dehydration or over exertional exercise may set you up to have a heat Injury.
Bodily Heat versus Environmental Heat
Body temperature is maintained within a narrow range by balancing heat load with heat dissipation. The body’s heat load results from both metabolic processes and absorption of heat from the environment. Evaporation is the principal mechanism of heat loss in a hot environment, but this becomes ineffective above a relative humidity of 75 percent. The other major methods of heat dissipation — radiation (emission of infrared electromagnetic energy), conduction (direct transfer of heat to an adjacent, cooler object) and convection (direct transfer of heat to convective air currents) — cannot efficiently transfer heat when environmental temperature exceeds skin temperature (typically 35ºC or 95ºF).
How Heat Injury Occurs
Heat-related illnesses result from excessive heat exposure caused by increased environmental heat, the inability of the body to dissipate it’s own internal heat or a combination of these two factors. Injuries can start small and escalate quickly and, often, unexpectedly.
Signs of Heat Injury
It is best to be alert to early signs of developing heat injury:
- Rash on the skin
- Swelling
- Lightheadedness
- Muscle cramps
Signs of Advanced Heat Injury
Advanced symptoms of a heat Injury can include the following:
- Fatigue or heat exhaustion (core body temp < 104)
- Increased heart rate
- Sweating
- Nausea
- Vomiting
- Dizziness
- Severe thirst
- Mental confusion
- Loss of consciousness
- Syncope
All of these can progress to heat stroke (core body temp > 104-105) unless cooling and rehydration is performed quickly. A heat stroke is very dangerous and evident with central nervous system impairment, obtunded, collapse, with abnormal electrolytes and internal vascular injuries possible.
How to Stay Safe in the Heat
It is best to stay safe in the heat by staying in shaded areas as much as possible when outdoors. If you know it’s going to be a hot day, have plans to have shade available, be it a sun umbrella, a tent or a shelter.
If exercising, make plans to do this as early in the hot summer days as possible, avoid exposure to peak sun intensity between 2-4 p.m. daily.
Have plenty of fluids available, including electrolyte supplementation or salt.
Be sure to prepare in advance of going into a hot climate with acclimatization efforts or training prior, to include proper daily hydration ahead of time, as well as maintaining thorough sleep hygiene and a rested state.
Talk to Your Provider
If you know you may be exposed to high heat conditions, seek the advice of your WakeMed primary care doctor ahead of time and build a plan together in preparation. Let your provider know if you have ever been victim to a heat injury in the past. Having had a prior heat injury can predispose you to a repeat injury.
About Michael Moore, MD
Dr. Moore’s clinical interests include prevention and treatment of diabetes, heart disease and hypertension. He is also interested in adolescent and sports medicine and committed to creating a wellness program for every patient. He embraces patient education and compassionate care with a goal of helping patients understand how to prevent disease, minimize its progression and establish a strong plan of action for best outcomes.
He completed his residency in family medicine at Womack Army Medical Center at Fort Bragg. He went on to complete 12 years of active duty, serving as a family physician and flight surgeon and earned more than a dozen military honors during his years of service.
Outside of medicine, Dr. Moore enjoys volunteering with his four children’s soccer and swimming programs. He is an avid soccer player and swimmer, and he also enjoys running, surfing and snowboarding as well as reading and music.
