Heatstroke Prevention and Treatment Standard Operating Procedures — Pre-Hospital
I. Prevention Measures for Heatstroke:
- Avoid working in high temperatures (>33°C) or direct sunlight and arrange adequate rest. Calculate the heatstroke risk index.
Formula: Outdoor temperature (°C) + Outdoor relative humidity (%). If the index exceeds 40 → Danger. - Get at least 6 hours of sleep daily.
- Replenish fluids adequately (cold water).
- Maintain adequate salt intake.
- Acclimatization (gradually increase training duration and workload for new recruits).
- Provide education and guidance to help exercisers understand the effects of heat.
- Drink 500 ml of water 2 hours before exercise.
- Drink water containing a small amount of salt if exercising for more than 1 hour.
- For every 0.5 kg of weight lost during exercise, replenish at least 500 ml of electrolyte solution.
II. Differential Diagnosis and Clinical Symptoms of Heatstroke:
- Heat cramps: Painful, involuntary muscle spasms after excessive exercise in a high-temperature environment.
- Heat exhaustion: Central nervous system fatigue leading to peripheral vasodilation, usually with heat production and dehydration; rapid heartbeat, low blood pressure, headache, agitation, nausea and vomiting, decreased coordination, weakness, dizziness, possible cramping, body temperature below 40.6°C.
- Heatstroke: Heat exhaustion symptoms with body temperature exceeding 40.6°C, plus confusion, delirium, dizziness, unsteady gait, abnormal behavior, inappropriate speech, seizures, and coma.
III. Initial Treatment for Heatstroke:
- Move the patient to a cool, shaded area.
- Remove upper clothing and outer pants.
- Assess level of consciousness and vital signs.
- If vomiting, place patient on their side to prevent aspiration pneumonia.
- Measure rectal temperature. If above 40.6°C, wet the patient and use fan cooling, and place ice packs on the neck, axillae, and groin.
- If excessive sweat and urine have been discharged, replenish with saline solution (0.1–0.15 g salt per liter of water).
- If urine output decreases, administer cold electrolyte solution. Never give plain water.
- Transport the patient in an open, well-ventilated vehicle to the hospital as quickly as possible. Continue cooling treatment during transport.
- If transport time exceeds 10 minutes, administer 500 ml of normal saline intravenously.
- If the soldier begins shivering or rectal temperature reaches 38°C during transport, stop cooling.
Heatstroke Prevention and Treatment Standard Operating Procedures — Post-Arrival
I. Monitoring:
- Monitor vital signs (EKG monitor, blood pressure monitor, A-line).
- Monitor level of consciousness (GCS).
- Monitor respiratory rate and oxygen saturation (SaO2).
- Monitor rectal temperature and skin temperature (maintain rectal temperature <39°C and skin temperature 30–33°C).
- Monitor intake/output and body fluid status (CVP, PiCCO).
II. Examinations:
- Complete blood count (CBC).
- Biochemistry: BUN, Creatinine, AST, ALT, Na, K, Cl, uric acid, phosphate, bilirubin, LDH, CPK, myoglobin, albumin, amylase, lactate.
- Coagulation: PT, PTT, D-dimer, FDP, Fibrinogen.
- Arterial blood gas analysis: pH, PCO2, PO2, HCO3.
- Urinalysis: urine routine, urine biochemistry (urine Na concentration, urine/plasma urea).
Chest X-ray, KUB, CT scan of brain as indicated.
III. Treatment:
- Establish a medical team and consult relevant departments. Transfer to a heatstroke ward or ICU with equivalent facilities for further treatment.
- Immediate cooling: Use major artery cooling method (neck, axillae, groin) to rapidly reduce core body temperature to 39°C.
- Maintain blood pressure: Adequate fluid replacement (approximately 2000 ml of normal saline), appropriate use of vasopressors to maintain mean arterial pressure above 60 mmHg.
- Respiratory: Administer oxygen. Consider endotracheal intubation if respiratory distress, altered consciousness, or seizures occur.
- Fluid replacement: Administer 1 to 1.5 liters of isotonic solution (normal saline) in the first two hours, followed by 250 ml per hour thereafter.
