The Collapsed Firefighter: Heat Illness vs. Cardiac Arrest on Scene
You are the EMS medical director responding as a field observer with a busy urban fire-based EMS agency. At 14:20 on a 97°F day with 60% humidity, crews are on scene of a two-alarm warehouse fire. During rehab, a 44-year-old firefighter in full turnout gear with 20 minutes of interior work collapses. Bystanders report he was confused, then slumped over. On your arrival he is supine on the pavement, unresponsive, with agonal gasps at about 6/min. Radial pulse is not palpable; a carotid check by a paramedic is reported as 'maybe.' Skin is hot and dry. Core temp by temporal scanner reads 40.1°C. The nearest hospital with a cath lab is 12 minutes by ground; the nearest ED is 5 minutes. There are 3 paramedics and 4 EMTs on the rehab sector.
1. What is your immediate priority in the first 60 seconds, and how do you resolve the 'maybe pulse' ambiguity?
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Treat this as cardiac arrest until proven otherwise. Agonal gasps plus unresponsiveness plus an unreliable pulse check in a collapsed firefighter is a peri-arrest/arrest picture. The first 60 seconds should be: (1) move him out of the hot zone to a shaded, ventilated area; (2) initiate high-quality CPR and attach a monitor/defibrillator without delay - do not spend time on repeated pulse checks or on cooling before rhythm assessment. The 'maybe pulse' should be resolved by a single organized 10-second carotid check simultaneous with rhythm analysis; if the monitor shows a shockable rhythm (VF/pVT), defibrillate immediately. If it shows organized electrical activity, reassess pulse with the monitor attached. The teaching point: in a hot environment, do not let heat-illness framing delay defibrillation. If the rhythm is asystole/PEA, begin cooling aggressively while continuing CPR.
2. If he is in PEA arrest with a core temperature by esophageal probe of 40.6°C, how does your resuscitation strategy differ from a standard nontraumatic PEA arrest?
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Standard ACLS still applies, but heat stroke changes priorities. Continue high-quality CPR and standard epinephrine dosing; do not withhold ACLS because of hyperthermia. The defining intervention is rapid cooling: cold water immersion or ice packs to neck, axillae, and groin, cold IV fluids, and cold gastric/rectal lavage if available - goal is to reduce core temp toward 38–39°C. Do not delay transport to a cooling-capable facility; the 5-minute ED is appropriate if it can continue cooling, but if it cannot, the 12-minute cath-lab hospital may be the better destination only if it has active cooling capability - confirm by radio. Key differences from standard PEA: (a) hyperkalemia and rhabdomyolysis are likely, so consider empiric calcium and sodium bicarbonate only if you suspect hyperkalemia (wide QRS, peaked T); (b) do not use the temporal scanner as the cooling target - it is unreliable in hyperthermia; use esophageal or rectal; (c) stop cooling at ~38.5°C to avoid overshoot. The trap: withholding cooling until ROSC. Cooling during CPR is indicated.
3. After 8 minutes of CPR the patient achieves ROSC with a core temp of 39.8°C. He remains unresponsive. What is your transport decision and what do you tell the receiving facility?
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Transport to the nearest ED capable of continued active cooling and post-arrest care - in this scenario the 5-minute ED, unless it lacks ICU capability, in which case the 12-minute hospital. The decision is driven by time-to-continued-cooling and post-arrest bundle, not by cath lab proximity, because the arrest is presumed heat-related and not clearly cardiac. Radio report should include: witnessed collapse with confusion, agonal respirations, PEA arrest, ROSC at 8 minutes, core temp trajectory (40.6°C → 39.8°C), cooling methods used, total downtime, and the need for continued cooling, rhabdomyolysis workup, and possible hyperkalemia. Do not declare the patient 'cooled' at 39.8°C - continued cooling to 38–39°C is still required. Also flag the occupational context for the receiving team and for the fire department's injury reporting.