Forty Patients, Two Lanes, Four Degrees
January, 4 °C, steady rain. A freight derailment has released an unknown liquid that pooled and splashed 40 people at a trackside market. Twenty-eight are ambulatory, twelve are not. Two are children under 5, one uses a wheelchair, and one is a 78-year-old with chest pain. Your decon corridor has two lanes, one 20 x 20 ft inflatable tent, ambient hydrant water at roughly 10 °C, no heated water, and six trained decon staff. The receiving hospital is 20 minutes away and says it can accept 8 patients in the next hour. Media are broadcasting from the perimeter. Runoff from the site drains to a storm sewer that feeds a creek 300 m away.
1. Sequence and prioritize decontamination for 40 casualties with two lanes and six staff.
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Sequence: triage first, then clothing removal for everyone, then lane assignment by ambulation and acuity.
- Triage before decon, at the edge of the hot zone, with re-triage after decon. Life threats travel with the patient through the corridor; they do not wait for a shower.
- Clothing removal is the highest-yield step - it removes the large majority of the contamination load and takes seconds. Do it for all 40 before anyone gets wet. Cut, do not pull, over the head.
- Two lanes, but not the same job:
- Lane A: ambulatory self-decon with staff coaching - high throughput, roughly 2–3 min per person, so the 28 ambulatory can clear in well under an hour.
- Lane B: non-ambulatory on backboards and roller systems, staff-performed, slower. This is where your six people go.
- Do not default to ambulatory-first purely for speed. The non-ambulatory include the most likely to have prolonged contact with pooled liquid and the highest absorbed dose. Split staff so Lane B starts immediately rather than after the ambulatory queue.
- Special handling: the wheelchair user is transferred to a decon roller, not lifted through a shower chair; the two under-5s are washed by a parent or staff with the parent present; the 78-year-old with chest pain gets a monitor, oxygen, and a provider at the head of the lane.
Re-triage the entire group after decon - a patient who looked stable in the cold zone can deteriorate once wet, cold, and undressed.
2. How do you balance hypothermia risk against contamination for the toddler and the 78-year-old?
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Neither is a reason to skip decon, and neither is a reason to stand in a wet tent. The answer is a short, warm, fast process.
The physics: children have a high surface-area-to-mass ratio and lose heat faster than adults; a wet toddler at 4 °C with any wind is a hypothermia case in minutes. The 78-year-old with chest pain is at risk from cold-induced vasoconstriction and shivering, which increases myocardial demand.
Practical countermeasures:
- Heat the tent before the first patient (portable heater, or at minimum block wind on three sides and keep the floor dry).
- Cap water contact: 60–90 seconds of washing with a detergent solution, focusing on exposed skin and the areas the liquid actually contacted, not a full-body scrub.
- Dry immediately and aggressively with warmed blankets; do not let a wet patient wait in a queue.
- Keep the run-off and the wet zone separate from the drying zone - a single tent does both jobs badly, so stage drying outside the wet area under cover.
For the 78-year-old specifically: life threats take priority over decontamination sequence but not over decontamination itself. Treat on a backboard at the head of the lane: oxygen, monitor, IV access established, and wash the exposed areas while a blanket covers the trunk. He goes into the ambulance decontaminated, not contaminated and en route. Secondary contamination of the ambulance and crew is a real and preventable harm.
3. Address the runoff into the storm sewer and the media presence.
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Runoff:
- Assume the liquid is hazardous until identified. Two decon lanes running continuously will generate hundreds of liters of contaminated water.
- Immediate action: berm or dam the flow path with soil, sandbags, or absorbent booms, and block the storm drain inlet with a drain cover or a temporary seal before you start washing. Divert to a low point and contain.
- Notify the water utility and the environmental regulator now, not after the fact. There are likely notification deadlines tied to the release and to the surface water pathway; the creek 300 m downstream makes this urgent.
- Document the volumes and the containment method - remediation cost and legal exposure both turn on whether you contained promptly.
Media:
- They are not the priority and they are not the enemy. Assign one person, at the perimeter, with a short statement: what happened, what you are doing, where families can go for information, and a request for space.
- Do not confirm the identity of the substance before you know it, and do not speculate about terrorism.
- The operational risk is real: media vehicles blocking the ambulance egress lane, and patients walking past live cameras undressed. Route patient movement away from the perimeter sight line and screen the decon corridor.
Judgement point: the hospital's eight-patient capacity is not your bottleneck - decon is. Clearing eight patients through a proper corridor beats clearing twenty through a bad one, and untriaged patients must not be released to the media or to family.