Level 2 of 6Must-remember

Mass casualty and disaster triage

Assess, manage and stay safe — enough on its own

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The card — assess, manage, caution

Assessment— look, ask, measure

Declare what kind of incident this is: a major incident is any event whose number, severity, type or location of casualties requires extraordinary arrangements because demand exceeds the resources immediately available — it is defined by the mismatch, not by a casualty count.
Separate the ambulant from the treatment area first: the first wave arrives early and is the least injured, the seriously injured arrive later, and an unprepared department is saturated by minor injuries by the time they come.
Sort every casualty with the Triage Sieve in under 30 seconds using only walking ability, respiration and perfusion — no diagnosis, no undressing, no blood pressure, and only two permitted interventions: control of catastrophic haemorrhage and opening the airway.
Sieve step by step in an adult: control catastrophic external haemorrhage first (Priority 1); walks on command means Priority 3; not breathing after the airway is opened means Dead (no rescue breaths in an adult); breathing only after the airway is opened means Priority 1.
Sieve physiology in an adult: respiratory rate below 10 or above 29/min is Priority 1; capillary refill over 2 seconds, pulse above 120/min or an absent radial pulse is Priority 1; none of these makes the casualty Priority 2.
Sieve in a child aged 1–10 years: give 5 rescue breaths before declaring dead; respiratory rate below 20 or above 40/min, capillary refill over 2 seconds, pulse above 140/min or absent radial pulse is Priority 1.
Sieve in an infant under 1 year: the walking test does not apply and the infant is assessed directly; 5 rescue breaths before declaring dead; respiratory rate below 20 or above 50/min, capillary refill over 2 seconds, pulse above 160/min or absent brachial pulse is Priority 1.
Use the colour codes so everyone understands: P1 immediate (red), P2 urgent (yellow), P3 delayed or minor (green), dead (white or black) and, where authorised, expectant (blue).
Immediate danger signs that override any algorithm: absent or noisy respiration; visible arterial or pooling haemorrhage; a penetrating wound to the chest, abdomen, neck or axilla; respiratory distress with unilateral absent breath sounds and hypotension; hoarseness, stridor or soot in the airway after fire; a tense abdomen; loss of the radial pulse; a Glasgow Coma Scale score below 9 or a fall of 2 or more points; a limb compressed for over an hour; a circumferential burn; miosis with bronchorrhoea; and vomiting within an hour of radiation exposure.
Measure a capillary blood glucose in everyone with altered consciousness — it is the one universal test, because hypoglycaemia is common, rapidly reversible and repeatedly missed.
Learn the deceiving presentations: the ambulant blast casualty who develops blast lung hours later; the crowd-crush victim with no external injury; the well-looking trapped patient who arrests on extrication; and the high-voltage casualty whose small skin wounds conceal extensive deep necrosis.
Adjust for the elderly: reduced physiological reserve and beta-blockade blunt the tachycardia the algorithms depend on, so a heart rate of 90 may accompany severe hypovolaemia; failure to walk may reflect baseline immobility rather than injury, and anticoagulation converts a minor head strike into an intracranial haemorrhage that declares hours later.
Adjust for children: cardiovascular compensation is efficient and blood pressure is preserved almost to the point of arrest, so hypotension is a pre-terminal sign, respiratory arrest usually precedes cardiac arrest, and a non-ambulant infant must never be given low priority simply because it did not walk.
Adjust for pregnancy: plasma volume expansion permits 30–35% of the circulating volume to be lost before conventional thresholds are breached while uteroplacental perfusion has already fallen, and aortocaval compression beyond about 20 weeks requires left lateral tilt or manual uterine displacement.
Re-triage on a clock: triage is a verb. Immediate-priority casualties need continuous reassessment, urgent casualties at least every 30 minutes, and delayed casualties at least hourly and before any discharge decision.
Assume the incident category predicts the injury pattern: earthquake and building collapse give crush injury, dust asphyxia and prolonged entrapment; explosion gives the four blast mechanisms and the hazard of secondary devices; enclosed-space fire gives thermal airway injury, burns, carbon monoxide and cyanide in one casualty; chemical release gives contaminated casualties who can injure those who treat them; crowd events give compressive asphyxia in victims with no external injury.

Management— do this, in order

Follow the modified primary survey, catastrophic haemorrhage before airway, and remember that four interventions dominate early survival and can all be delivered in seconds by an unaided clinician: opening the airway, arresting external haemorrhage, decompressing a tension pneumothorax, and giving rescue breaths to the apnoeic child.
Decontaminate before treating, except for immediate life threats: removal of clothing removes the great majority of chemical and radiological contamination and is followed by copious water irrigation — treating a contaminated casualty inside a clinical area risks converting the facility itself into part of the incident.
Control haemorrhage in steps: direct pressure, then wound packing with a haemostatic dressing for junctional bleeding, then a windlass tourniquet placed proximally and tightened until bleeding stops and the distal pulse is lost, with the time recorded; apply a pelvic binder at the level of the greater trochanters for suspected pelvic fracture.
Decompress a tension pneumothorax immediately on clinical grounds by needle or finger thoracostomy in the fourth or fifth intercostal space in the anterior axillary line, proceeding to formal intercostal drainage — the lateral approach is preferred in adults because chest wall thickness at the second intercostal space frequently exceeds standard cannula length, and it never awaits a radiograph.Doctor / NurseNot available at your setup — Chest drain / tube thoracostomy.
Resuscitate to a palpable radial pulse and preserved consciousness (roughly a systolic pressure of 80–90 mmHg) in uncontrolled haemorrhage until surgical control is achieved, but target at least 110 mmHg where traumatic brain injury is suspected.Doctor / Nurse
Give tranexamic acid as early as possible and within 3 hours of injury for significant traumatic haemorrhage or suspected internal bleeding: adult 1 g IV over 10 min then 1 g IV over 8 h; paediatric 15 mg/kg IV over 10 min (maximum 1 g) then 2 mg/kg/h over 8 h.Doctor / Nurse
Crystalloid is a holding measure only: adult 250 mL boluses titrated to a radial pulse; paediatric 10 mL/kg boluses, moving to blood after 20 mL/kg in haemorrhagic shock — balanced blood components in approximately equal ratios of red cells, plasma and platelets are preferred, and the lethal triad of hypothermia, acidosis and coagulopathy is prevented by actively warming patient and fluids.Doctor / NurseNot available at your setup — Blood & blood products.
Analgesia is a triage intervention, not a comfort measure, because pain raises respiratory rate and heart rate and corrupts subsequent Sort scores: morphine 2.5–5 mg IV repeated every 5–10 min to effect (halve in the elderly, hypotensive or intoxicated), paediatric 0.1 mg/kg IV in divided doses and 0.05 mg/kg under 3 months.Doctor / Nurse
Ketamine suits the shocked or trapped casualty because it preserves airway reflexes and blood pressure: 0.25–0.5 mg/kg IV slowly, or 2–4 mg/kg IM, the same in children; fentanyl is 1 microgram/kg IV or 1.5 micrograms/kg intranasal (paediatric 1.5 micrograms/kg intranasal where IV access is impractical); paracetamol is 1 g orally or IV 6-hourly, paediatric 15 mg/kg orally or IV 6-hourly to a maximum of 60 mg/kg/day; naloxone is 400 micrograms IV/IM repeated, paediatric 10 micrograms/kg IV repeated.Doctor / Nurse
Start intravenous fluid before extrication wherever possible in crush injury: adults isotonic saline 1–1.5 L in the first hour then 300–500 mL/h titrated to a urine output of 1–2 mL/kg/h; children 15–20 mL/kg/h initially then titrated — and avoid potassium-containing fluids.Doctor / Nurse
Treat hyperkalaemia at the bedside on the ECG without awaiting a laboratory result: calcium gluconate 10%, 10–30 mL IV over 5–10 minutes with cardiac monitoring, repeated if the ECG does not improve (paediatric 0.5 mL/kg, maximum 20 mL); 10 units of soluble insulin with 25 g glucose IV over 15–30 minutes; nebulised salbutamol 10–20 mg (2.5 mg under 5 years); refractory hyperkalaemia or anuria requires renal replacement therapy.Doctor / NurseNot available at your setup — Dialysis / renal replacement.
In burns the airway is the emergency, not the skin: hoarseness, stridor, soot, singed nasal hair, facial burns or fire in an enclosed space mandate early intubation before oedema makes it impossible; circumferential full-thickness burns may require escharotomy.Doctor / NurseNot available at your setup — Endotracheal intubation kit.
Estimate and resuscitate the burn: Rule of Nines in adults (head 9%, each arm 9%, each leg 18%, anterior trunk 18%, posterior trunk 18%, perineum 1%) or the palm with fingers as about 1%, not counting erythema and using a paediatric chart in children; cool with running water for 20 minutes and cover with clear film, never ice; give 3–4 mL x body weight (kg) x %TBSA of balanced crystalloid over 24 hours, half in the first 8 hours from the time of the burn, then titrate to urine output, with children additionally needing maintenance fluid containing glucose.Doctor / Nurse
Suspected cyanide poisoning after fire is treated with hydroxocobalamin 5 g IV over 15 minutes (paediatric 70 mg/kg).Doctor / Nurse
Cholinergic (organophosphate or nerve agent) exposure: atropine 1.2–2 mg IV in adults (20 micrograms/kg in children), doubled every 3–5 minutes until the chest is dry — the endpoint is drying of secretions and reversal of bronchoconstriction, not pupillary dilatation, and very large cumulative doses may be needed; add an oxime such as pralidoxime, typically 30 mg/kg IV over 20 minutes then 8 mg/kg/h, and give benzodiazepines for seizures.Doctor / Nurse
After radio-iodine exposure give potassium iodide as early as possible — 130 mg orally as a single dose in adults, 65 mg at 3–12 years, 32 mg from 1 month to 3 years and 16 mg under 1 month — efficacy falling sharply beyond a few hours; management of acute radiation sickness is otherwise largely supportive, and life-threatening injuries are always treated before decontamination.
Give early antibiotics for contaminated wounds, open fractures and blast wounds: co-amoxiclav 1.2 g IV 8-hourly, or ceftriaxone 1 g IV daily with metronidazole 500 mg IV 8-hourly, with tetanus toxoid for any breached skin barrier and uncertain immunisation status, and immunoglobulin for heavily contaminated wounds.Doctor / Nurse
Use the expectant category only during genuine, declared, uncompensated demand: expectant casualties still receive analgesia, oxygen, warmth, human company and continued re-triage, and are re-categorised to immediate if capacity is restored.

Caution— what harms

Over-triage is not a safe error: each over-triaged patient consumes a bay, a team, imaging capacity and blood that a genuinely critical patient required, and over-triage above roughly 50% is associated with a clear rise in mortality among the truly critical.
Under-triage kills directly and individually — the answer to both errors is not a cleverer initial sort but one that is fast, crude and repeated.
Clinical judgement may raise a priority but must never lower it: a normal Sort score in a patient with a penetrating truncal wound, a tense abdomen, a positive tourniquet, an inhalational or circumferential burn, pregnancy beyond 20 weeks, or an extreme of age with significant mechanism, is still immediate priority.
Never let imaging delay a time-critical intervention: tension pneumothorax is decompressed on clinical grounds and never awaits a radiograph, an unstable patient does not belong in a scanner, and CT is the principal bottleneck.Not available at your setup — CT scan.
A normal test does not exclude the injury: haemoglobin is normal in early haemorrhage and its normality is meaningless, an initially normal chest radiograph does not exclude blast lung, a negative eFAST does not exclude injury, and pulse oximetry is falsely normal in carbon monoxide poisoning.Not available at your setup — Ultrasound.
Do not await laboratory confirmation before treating: plasma or red cell cholinesterase confirms organophosphate exposure retrospectively and is never awaited, and hyperkalaemia is treated on the ECG rather than the number.
Avoid potassium-containing fluids in crush injury, and remember the patient deteriorates at the moment of rescue — hyperkalaemia may precipitate arrest within minutes of release.
Do not correct hypocalcaemia in rhabdomyolysis unless symptomatic: hypocalcaemia with hyperphosphataemia is expected, and urinary alkalinisation with bicarbonate and the use of mannitol are contested, with real risks of alkalosis worsening hypocalcaemia and mannitol precipitating renal injury.
Permissive hypotension does not apply in traumatic brain injury, where at least 110 mmHg is targeted to preserve cerebral perfusion — a genuine conflict when both coexist, for which no evidence-based resolution exists.
Tranexamic acid may be harmful beyond 3 hours from injury, and benefit declines with every minute of delay.
Never use ice on a burn, never count erythema in the burned area, and never resuscitate a child with an adult burn chart because the proportionally larger head alters area estimation.
In cholinergic poisoning the endpoint of atropine is a dry chest, not dilated pupils — titrating to the pupils leads to gross under-dosing.
Treating a contaminated casualty inside a clinical area can convert the treating facility into part of the incident; clothing removal comes first, but life-threatening injuries are always treated before decontamination.
The patient who looks well after a blast, a crush or a high-voltage electrical injury may not be well — delayed declaration is the rule in these mechanisms, and observation with reassessment is part of the treatment; the occult tension pneumothorax and the evolving crush syndrome are both found in the minor-injury area looking well.

Refer / escalate

Escalate the moment the mismatch between demand and resources cannot be corrected by mobilising more resources — declare the incident, request additional teams, blood and transfer capacity, and record the time; transfer individually for surgical haemorrhage control, blast lung requiring ventilation, refractory hyperkalaemia or anuria needing renal replacement therapy, major burns with inhalational injury, and any casualty whose priority has been raised by clinical judgement.

The card — assess, manage, caution

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