PHTLS Environmental Trauma (Hypothermia, Heat Emergencies, and Drowning)

Question 1

A backcountry skier is found unresponsive with a core temperature of 28°C (82.4°F) and is in ventricular fibrillation.
According to current resuscitation guidelines taught in PHTLS, what is the correct immediate action?

Accepted Answer

Attempt defibrillation up to 3 times, then defer further shocks until rewarming above 30°C

Answer

Do not defibrillate — hypothermic VF cannot be converted and defibrillation is contraindicated

Answer

Administer amiodarone IV before any defibrillation attempt

Answer

Begin CPR and transport without defibrillation until the patient reaches hospital

Question 2

Which two clinical findings best allow a PHTLS provider to distinguish severe hypothermia from mild hypothermia in the field without a thermometer?

Accepted Answer

Cessation of shivering and declining level of consciousness

Answer

Skin color and capillary refill time

Answer

Heart rate below 60 and systolic BP below 90

Answer

Absence of peripheral pulses and fixed pupils

Question 3

A construction worker is found with hot, dry skin, confusion, and a core temperature of 41°C (105.8°F). What is the HIGHEST treatment priority?

Accepted Answer

Begin rapid active cooling immediately

Answer

Establish IV access and administer a fluid bolus

Answer

Apply supplemental oxygen and transport without active cooling

Answer

Assess and stabilize the airway before any cooling measures

Question 4

A near-drowning victim is pulled from cold water, is apneic, and has no palpable pulse. Which action takes HIGHEST priority according to PHTLS principles?

Accepted Answer

Begin CPR immediately — do not delay resuscitation for rewarming

Answer

Rewarm the patient before initiating CPR to optimize cardiac response

Answer

Assess for spinal injury before moving the patient from the water

Answer

Suction the airway for 90 seconds to clear aspirated water before ventilating

Question 5

Passive rewarming alone (removing wet clothing, dry insulating blankets, shelter from wind) is the appropriate field rewarming strategy for which hypothermia category?

Accepted Answer

Core temperature above 32°C — mild hypothermia where the patient is still shivering

Answer

Core temperature below 28°C — the patient needs passive rewarming only

Answer

Core temperature 28–32°C — moderate hypothermia

Answer

Passive rewarming is never appropriate in the field

Question 6

Which feature MOST reliably distinguishes heat exhaustion from heat stroke in a field setting?

Accepted Answer

Heat exhaustion is associated with normal or near-normal mentation; heat stroke involves CNS dysfunction

Answer

Heat exhaustion causes anhidrosis (dry skin); heat stroke causes diaphoresis

Answer

Heat stroke presents with a higher heart rate than heat exhaustion

Answer

Heat exhaustion affects only younger patients; heat stroke affects only the elderly