Heat stress, heat stroke and dehydration are common illnesses that can be caused by excessive exposure to hot weather. Nursing home residents are highly susceptible to heat related illnesses due to their medical conditions. They perspire less, which prevents the body from cooling itself. Many nursing home residents take medications that affect the body's natural ability to adjust to heat. For example, diuretics (sometimes prescribed for high blood pressure) prevent the body from storing fluids and restrict the opening of blood vessels near the skin's surface. Certain tranquilizers and drugs used to treat Parkinson's disease interfere with perspiring. Chronic conditions such as circulatory problems, diabetes, a previous stroke, or a damaged heart also upset the body's normal responses to heat.

Heat stress is the burden that hot weather places on the body, especially the heart, which must work harder to keep a normal body temperature. Early warning signs of heat stress include loss of appetite and feeling listless and uncomfortable. Serious warning signs are dizziness, rapid heartbeat, throbbing headache, breathing problems, chest pain, cramps, deepening urine colors, less frequent urination, diarrhea, nausea, vomiting and mental changes like delirium.

Heat stroke is the most serious heat-related illness. It occurs when the body becomes unable to control its temperature. The body's temperature rises rapidly, the sweating mechanism fails, and the body is unable to cool down. The body temperature may rise to 106 F or higher within 10 to 15 minutes. Heat stroke can cause death or permanent disability if emergency treatment is not provided.

Dehydration is a dangerous lack of water in the body caused by inadequate intake or excessive loss of fluids through sweating, vomiting or diarrhea.

Not only is it good sense to keep the elderly away from extreme conditions, it's also a federal law:

"To prevent illness, suffering and death caused by excessive heat, nursing homes are required to be well ventilated and to maintain comfortable and safe temperature levels at all times. Nursing homes that were certified for Medicare and/or Medi-Cal after October 1, 1990 must maintain a temperature between 71-82 degrees." (Title 42, Code of Federal Regulations, Section 483.15(h)(6))