Catastrophic external haemorrhage comes first (the C before ABC): direct pressure, tourniquet, or haemostatic packing. Activate the major trauma network and major haemorrhage protocol early.
C then A: catastrophic bleed and airway
- Control compressible external haemorrhage before airway
- Manual in-line stabilisation of the C-spine
- Airway: jaw thrust, suction, definitive airway if GCS 8 or less
B Breathing
- Inspect, palpate, percuss, auscultate
- Tension pneumothorax: immediate decompression then chest drain
- Open pneumothorax, massive haemothorax, flail; target SpO2 94 to 98%
Stable (responds)
- Normal physiology after primary survey
- Complete the secondary survey
- Imaging and monitor
Transient responder
- Transient response to blood
- Ongoing occult bleeding
- CT and surgical or IR plan
Non-responder / in extremis
- Persistent shock, catastrophic bleed
- Activate MHP, damage control
- Immediate surgery or IR
C-ABCDE loop
1
C Circulation
Two large cannulae, bloods and crossmatch, warmed blood. Pelvic binder for suspected pelvic fracture, tourniquet for limb bleed, TXA within 3 h. Permissive hypotension until surgical control (not in head injury).
Two large cannulae, bloods and crossmatch, warmed blood. Pelvic binder for suspected pelvic fracture, tourniquet for limb bleed, TXA within 3 h. Permissive hypotension until surgical control (not in head injury).
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2
D Disability
GCS, pupils, glucose, lateralising signs. Assume spinal injury until cleared. Beware the hypoxic or hypotensive cause of a low GCS.
GCS, pupils, glucose, lateralising signs. Assume spinal injury until cleared. Beware the hypoxic or hypotensive cause of a low GCS.
↓
3
E Exposure
Expose fully but prevent hypothermia (warm the patient and fluids). Log roll with team control when appropriate.
Expose fully but prevent hypothermia (warm the patient and fluids). Log roll with team control when appropriate.
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4
Reassess
Reassess ABCDE after every intervention and whenever the patient deteriorates. Adjuncts: FAST or trauma CT, catheter, analgesia.
Reassess ABCDE after every intervention and whenever the patient deteriorates. Adjuncts: FAST or trauma CT, catheter, analgesia.
Lethal triad
- Hypothermia, acidosis and coagulopathy feed each other
- Warm the patient, give balanced products, replace calcium
- Damage-control surgery, then resuscitation
Pitfalls
- Starting airway before controlling exsanguinating bleeding
- Large clear-fluid boluses diluting clotting factors
- Permissive hypotension in traumatic brain injury
- Missing hypothermia under the trauma blanket
MedPrep - www.medprep.uk - Educational revision aid only. Not clinical guidance. Doses are adult examples; check the BNF, current guidelines and local policy, and seek senior advice. Nov 2026