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MedSys / Emergencies / Catastrophic bleeding

Emergencies & first aid · Chapter 9 of 26

Catastrophic bleeding

Someone can bleed to death from a limb in three to five minutes. That is shorter than an ambulance response almost anywhere.

Someone can bleed to death from a limb in three to five minutes. That is shorter than an ambulance response almost anywhere, which makes this one of the few emergencies where what a bystander does in the first two minutes decides the outcome.

The change worth knowing. Tourniquets were taught for years as a desperate last resort that would cost the limb. That was wrong, and it came from wartime experience with improvised devices left on for many hours. Current first aid guidance treats direct pressure, then haemostatic dressing and/or tourniquet as a straightforward escalation. A correctly applied tourniquet on for the time an ambulance takes is very unlikely to cost a limb, and hesitating over one has cost lives.

The escalation, in order

  1. Hard, direct, uninterrupted pressure

    Straight onto the wound, with whatever is available, pressing hard enough that it is uncomfortable for you to maintain. Most bleeding stops here. Gloves if there are any, but do not go looking for them first.

  2. Do not lift it to look

    The commonest error. Every check disrupts the clot forming under your hands and restarts the bleeding. If blood soaks through, add more dressing on top and press harder — never remove what is already there.

  3. Pack a deep wound

    For a deep wound in the groin, armpit, neck or a deep limb wound where pressure alone is not working, push gauze — haemostatic if available, plain if not — firmly into the wound, filling the cavity, then press on top for at least three minutes. Not for the chest or abdomen, where you cannot reach the source.

  4. Tourniquet, for a limb that is still bleeding

    High and tight, above the wound, over a single bone if possible, and tighten until the bleeding stops — which will hurt, and is the point. A tourniquet that is not tight enough is worse than none, because it stops venous return without stopping arterial flow. Write the time on it, or on the person, and tell the crew.

  5. Never loosen it to check

    Once on, it stays on until a clinician removes it. Loosening releases the clot and restarts the loss.

Where a tourniquet cannot help, and what to do instead

  • Junctional bleeding — groin, armpit, neck, shoulder. There is no limb to compress above. Pack the wound hard and maintain pressure with your whole body weight if necessary.
  • Neck — direct pressure only, and never around the neck. Do not obstruct the airway or compress both sides.
  • Chest or abdomen — you cannot reach it. Pressure over the wound, lie them flat, keep them warm, and this is a load-and-go for the ambulance.
  • Improvised tourniquets are poor. A belt does not tighten enough and a narrow cord causes tissue damage. If you have to improvise, use something at least 4 cm wide with a rigid rod to twist. A proper windlass tourniquet in a car or a school kit costs about £15 and is one of the few pieces of equipment that genuinely changes outcomes.

Recognising blood loss before the blood pressure moves

Blood pressure is the last thing to fall, especially in children and fit young adults, who compensate hard and then crash. By the time systolic pressure drops they have already lost a great deal.

Earlier signsLater signs
Rising pulse rate. Pale, cool, clammy skin. Anxiety, restlessness, "something is wrong". Thirst. Capillary refill over two secondsConfusion and drowsiness. Weak thready pulse. Falling blood pressure. Rapid shallow breathing. Loss of consciousness
  • Lie them flat and keep them warm. Cold blood clots badly, and heat loss in a bleeding person is a genuine contributor to death. A foil blanket is not a comfort measure here.
  • Nothing to eat or drink, however thirsty they are — they may need surgery.
  • Children hide it better and have less to lose. A volume that is survivable in an adult can be catastrophic in a small child.
Nosebleeds, since they are the common version of this in a school. Sit up, lean forward, pinch the soft part of the nose — not the bony bridge — and hold for a full ten minutes without releasing to check. Leaning back sends blood into the stomach, causes vomiting, and hides how much is being lost. Get help if it continues past 20 minutes of proper pressure, follows a head injury, or the person takes anticoagulants.