Final answer:
Internal bleeding in a fractured extremity is typically controlled by splinting the extremity, which aids in reducing movement and supports the body's natural clotting mechanisms. Hence, option (4) is correct.
Step-by-step explanation:
Internal bleeding into a fractured extremity is MOST often controlled by splinting the extremity. Applying a tourniquet is a more extreme measure that may be necessary for severe or arterial bleeding that cannot be controlled by pressure or splinting. Keeping the patient warm and applying chemical ice packs can be supportive measures, but they do not directly control bleeding. Splinting helps to immobilize the fracture, which can minimize movement and reduce further injury to blood vessels, aiding in the control of bleeding.
When an injury occurs and a blood vessel is severed, the body responds through various mechanisms, including vascular spasm and the release of substances for blood clotting. The aim is to reduce blood loss and prevent shock, which can occur if blood pressure drops too drastically due to blood loss. The application of a splint helps support this natural clotting process by keeping the injured area as still as possible.