Hyperthermia Standing Order

HYPERTHERMIA (Heat Illness) State of unusually high core body temp Predisposing Factors: 1. Age of the patient: less tolerable in peds and geriatric. 2. Health of the patient: i.e. diabetics can become hyperthermic more easily because of the damage DM inflicts on their autonomic nervous system (thermoregulatory input, vasodilation, perspiration) 3. Medications: i.e. diuretics >dehydrartion,Beta Blockers<vasodilation, psychotropic's< CNS regulation

Predisposing factors continued: 4. Level of acclimation: adjusting to environment change 5. Length of exposure 6. Intensity of exposure 7. Environmental factors such as humidity and wind

Organ Systems Responsible for Heat Loss Skin: vasodilatation and perspiration Cardiovascular: increased cardiac output to compensate for peripheral vasodilatation with increased volumes of blood to periphery Respiratory: some degree of evaporation

Humidity Evaporation and perspiration are the primary and most effective methods of cooling At very high humidity, perspiration is totally ineffective

The Range of Heat Illnesses Heat Cramps: Painful, easily treated, acclimation occurs Heat Exhaustion: Serious but no organ damage, mild hyperpyrexia Heatstroke: Critical organ damage, significant mortality, markedly elevated body temperature, usually > 105’

Heat Cramps Painful contractions of larger muscle groups during or shortly after strenuous exercise in the heat Usually caused by replacement of water without adequate salt resulting in a low sodium state in the muscles Treated with cooling measures, fluid and electrolyte replacement via IV. No changes in mental status or fever

Heat Exhaustion Salt or water depletion in the face of heat stress Mild hyperpyrexia, nausea, vomiting, lightheadedness, dehydration with only minimal altered mental status Leads rapidly to heatstroke if not rapidly reversed Treated with cooling measures, also IV Normal Saline, further electrolyte replacement guided by serum electrolyte levels

Heatstroke Heatstroke results when the body’s thermoregulatory mechanisms are overwhelmed by the heat stress. The body’s temperature rises markedly with eventual multisystem organ failure.

Exertional and Classic Heatstroke Exertional: younger, physically fit with normal thermoregulatory systems –Frequently not dehydrated and may be wet with perspiration –Significantly elevated body temperature Classic: older or debilitated exposed passively to significant thermal stress over hours or days. –Ability to respond is compromised by CV disease, drugs, alcohol. – Usually perspiring for significant time and profoundly dehydrated

Organ Systems Affected by Heatstroke CNS Altered mental status always, posturing, paralysis, seizures, coma Cardiovasc High-output CHF, pulmonary edema, complete CV collapse Hepatic Central lobular necrosis (with elevated Liver Function Tests) RenalFrequent rhabdomyolysis,

Treatment of Heatstroke ABC’s Cooling measures to lower the patient’s temp to <101ºF within 1 hour. Prevent shivering as this raises the core body temperature Keep patient NPO. IV NS, fluid bolus’, O-2, cardiac monitor, Anticipate seizures: Rx valium True life threatening emergency so load and go to the closest E.D.

Take the test now. Must pass with 90%.

1. Review answers to test if made available. 2. Make sure your test info is completely filled in. 3. Collect test and mail to your Prehospital Manager. 4. Will receive 1 hour SAEMS CEU with in one week of mailing. 5. May begin using SAEMS Hyperthermia Standing Order as soon as you pass test with 90% & confirmed by your Prehospital Manager. 6. Questions? Call your Prehospital Manager.