Recognising severe bleeding and acting in the first minute

Severe bleeding is anything that spurts, soaks through clothing, or pools on the floor. Bright red blood arriving in pulses suggests an artery; a dark, steady flow usually means a vein. Either way, the priority is the same: slow the blood loss while help is on the way. If you are alone with the casualty, put your phone on speakerphone and call 999 yourself — the call handler will stay on the line and talk you through each step.

Before you touch the wound, protect yourself. Disposable gloves from a first aid kit, or even a clean carrier bag over your hands, reduce the risk of contact with someone else's blood. If the casualty is responsive, tell them what you are doing and that an ambulance is coming. Calm words slow everyone's heart rate, including yours.

Direct pressure is the single most important skill

Place a clean dressing, sterile gauze, or — failing that — a folded T-shirt over the wound and press firmly with the flat of your hand. Use both hands if you can, and lean your body weight over the wound rather than relying on tired arms. Pressure should be firm enough that it would hurt if you were pressing on your own skin. Hesitant pressure is the most common reason bleeding continues.

Keep pressing without lifting to check. Peeking breaks the clot that is forming. If you are pressing on a limb, the casualty is fully alert, and you do not suspect a fracture, raise the limb above the level of the heart while maintaining pressure.

Never remove anything embedded in the wound — a shard of glass, a knife, a piece of fencing. Press either side of the object instead, and build padding up around it.

If the dressing soaks through

• Do not remove the soaked dressing. Lifting it tears away any clot that has begun to form.
• Add another dressing or pad on top of the first and press harder.
• Keep adding layers until they hold, and maintain pressure with both hands.
• If you have a trauma dressing with a built-in bandage, use it — the pressure pad is designed to be tightened directly over the wound.

For bleeding from areas where you cannot easily press, such as the groin, armpit or neck, wound packing may be needed. Push gauze or clean cloth firmly into the wound, filling it from the deepest point outwards, then press hard over the top. It is uncomfortable for the casualty, but it can be life-saving.

Catastrophic limb bleeding and tourniquets

If a limb is bleeding so heavily that direct pressure is not controlling it, or the casualty is becoming drowsy, a tourniquet may be the only option. Purpose-made windlass tourniquets are increasingly found in UK workplace first aid kits and public access trauma kits. Apply one 5–7cm above the bleeding point, never over a joint, and tighten until the bleeding stops.

If you do not have one, a wide, strong band — a triangular bandage, a necktie, a strip of cloth — with a stick or pen as a windlass will work in an emergency. Never use thin cord, wire or shoelaces; they cut into the skin without compressing the artery beneath. Record the time of application on the casualty's skin or clothing, leave the tourniquet visible, and never loosen it. Ambulance crews will make that decision.

Watching for shock

Losing a significant amount of blood can send the body into shock, where vital organs are starved of oxygen. Signs include pale, clammy or grey skin, especially around the lips; fast, shallow breathing; a rapid, weak pulse; thirst; restlessness, anxiety or confusion; and later drowsiness or unresponsiveness.

• Lay the casualty down and raise their legs if their injuries allow.
• Keep them warm with a coat or blanket, but do not rub their limbs.
• Do not give food, drink or cigarettes. If they are thirsty, moisten their lips with a little water.
• Stay with them, keep talking, and reassure them that help is coming.
• If they become unresponsive but are still breathing, place them in the recovery position and monitor continuously.
• If they stop breathing normally, begin CPR and ask someone to confirm that 999 has been called.

Handing over clearly when the ambulance arrives

Stay with the casualty until the crew takes over, and keep your pressure on the wound until they tell you to release it. Be ready with the essentials: what happened and when, where the bleeding is, roughly how much blood has been lost, whether a tourniquet was applied and at what time, and any known medical conditions, allergies or medication such as blood thinners.

Afterwards, clean any blood from your skin with soap and warm water, and dispose of used dressings safely. Speak to your GP or NHS 111 if blood entered a cut, your eyes or your mouth — it is a sensible precaution, not an overreaction.

Finally, consider booking a practical first aid course. A few hours of hands-on training turns this knowledge into instinct, so that if the moment ever comes, you act rather than freeze. Keeping a well-stocked kit at home, in the car and at work — gloves, gauze, trauma dressings, a foil blanket and scissors — means everything you need is within reach when seconds matter.