IdentificationBlood vessels run close to the surface on the head, so any wound will bleed profusely.
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ManagementEncourage the casualty to lie down with the head and shoulders slightly supported. Cover the wound with a clean (ideally sterile) pad and apply firm pressure (but be aware of the risk of a skull fracture). Secure the pad in place with a bandage.
Because of the risk of head injury, medical assessment would be prudent.