THERMAL EMERGENCIES –
Heat Stroke, Causes, Predisposing Factors,
Emergency Care Procedures
and Treatment
THERMAL EMERGENCIES – Heat Stroke, Causes, Predisposing Factors, Emergency Care Procedures and Treatment
Thermal or heat emergencies fall into three categories of increasing severity: Heat cramps, heat exhaustion and heatstroke. Heat emergencies are caused by prolonged exposure to extreme heat. The following are common causes of heat emergencies: alcohol use, dehydration, heart disease, high temperatures or humidity, medications such as diuretics, neuroleptics, phenothiazines, and anticholinergics, prolonged or excessive exercise, sweat gland problems and too much clothing.
HEAT STROKE
Heat stroke is defined as increase in body temperature or hyperthermia that exceeds 41 degree celcius with lack of sweating associated with mental confusion. This is the most serious type of heat emergency. It is life-threatening and requires immediate and aggressive treatment. Heat stroke occurs when the body’s heat regulating mechanism fails. Heat stroke is a serious life threatening emergency wherein the victim’s cooling system has failed and prolonged high body temperature will likely result in brain damage or death.
Heat stroke usually results from doing heavy work in hot environments usually accompanied by inadequate fluid intake. Infants, children, obese adults and elderly people are more prone to heat stroke than young and healthy adults.
CAUSES OF HEAT STROKE
Working or exercising in hot conditions or weather without drinking enough fluids is the main cause of heat stroke. Heavy clothing and some skin conditions can also contribute to the occurrence of heat stroke. You can get heat stroke by not replacing lost fluids over days or weeks, or you can bring it on in a few hours by exercising strenuously on a hot day without drinking plenty of liquids first.
Liquids help to cool us down by allowing the body to produce sweat. However, liquids are also necessary for bodily functions, such as keeping up blood pressure. You can lose large amounts of body fluid in the form of sweat without noticing any effects, but at certain point the body will reserve the remaining fluid for vital functions, and stop sweating. The body’s core temperature shoots up, and cells start dying. Sweat evaporates more rapidly in dry weather, cooling the body more effectively than in humid weather. When working in humid conditions, the core temperature rises more rapidly.
PREDISPOSING FACTORS
- Non-acclimatization to high temperatures
- Pre-existing illness with fever
- High humidity
- Obesity
- Diabetes
- Alcoholism
- Birth defect with absence of sweat gland (Ectodermal dysplasia)
- Excess physical exertion or exercise
- Administration of sweat inhibiting drugs
SIGNS AND SYMPTOMS
The victim’s skin is hot, red and usually dry. The body temperature is very high, sometimes as high as 105 degrees. Deep breaths followed by shallow breathing, a rapid strong pulse followed by rapid, weak pulse, dilated pupils, headache, dizziness, restlessness, loss of consciousness/possible coma, hallucination, confusion, agitation, disorientation and possibly seizures or muscular twitching.
EMERGENCY CARE PROCEDURES
- Remember, heat stroke is a life-threatening emergency and requires prompt action
- Rapidly cool the victim in any manner possible
- Get victim out of the sun into a cooler area
- Remove clothing and wrap with wet towels or sheets if possible
- If cold packs or ice bags are available, pack one under each armpit, behind each knee, one on the groin, one on each wrist and one on each side of the neck
- The patient’s clothes have to be loosened so as to allow active air circulation
- Body and limbs have to be massaged in order to improve the blood circulation within body
- Do not give victim anything by mouth
- Provide victim high concentration of oxygen
- Victim must be transported to definitive care as soon as possible
- Drugs to treat epileptic fits are administered, if the need arises
- Shock is treated by supplying the body with sufficient fluids and by administering drugs, which increases the efficiency of the heart
TREATMENT
Immediate treatment for heat stroke is essential as death or permanent brain damage can occur within minutes. Emergency treatment is focused on cooling the patient as quickly as possible to a core body temperature 38.9 degree celcius. Cooling may be done by spraying water on the body, covering the patient with sheets soaked in ice water, or placing ice packs in the patient’s armpits and groin area. The patient’s temperature is not lowered further because they may start to shiver, and shivering will raise their internal temperature again.
If the patient is conscious, they may be given additional oxygen to breathe and intravenous fluids to restore their blood volume. In most cases these fluids will contain sugar in order to lower the risk of liver failure. Patients who are having muscle cramps or convulsions are usually given benzodiazepine tranquilizers, which relax the muscles and reduce the risk of damage to muscle tissue. The patient will be kept in the hospital for at least forty-eight hours after emergency treatment and monitored for brain damage, signs of liver failure, or other complications. This period of observation is necessary because heat stroke can damage almost all major body systems.