When treating a nosebleed, which action is important to prevent further bleeding?

Applying pressure to the bridge of the nose is crucial when treating a nosebleed because it helps to constrict the blood vessels, reducing blood flow and aiding in the clotting process. This method, typically recommended, encourages the formation of a clot and decreases the likelihood of further bleeding.

Instructing someone to lean back and blow their nose can be counterproductive, as it can cause blood to flow down the throat and potentially lead to choking or swallowing blood. Similarly, using a tourniquet on the neck is highly inappropriate and dangerous, as it could restrict blood flow and cause serious injury or complications. Spraying cold water on the nose may provide a temporary cooling effect, but it does not address the underlying issue of controlling the bleeding itself. Thus, applying pressure directly to the bridge of the nose is the most effective and appropriate action to take in this situation.