Final answer:
The prehospital treatment for a life-threatening hemorrhage in routine trauma care involves controlling the bleeding and restoring blood volume.
Step-by-step explanation:
In routine trauma care, the prehospital treatment for a life-threatening hemorrhage involves immediate action to control the bleeding and restore blood volume. One method is through intravenous administration of saline solution, which provides fluids and electrolytes equivalent to those in normal blood plasma. This helps replace some of the lost blood volume. In situations where type O blood is not immediately available, medics may use artificial blood substitutes that contain hemoglobin- and perfluorocarbon-based oxygen carriers, allowing for transfusions in the field without compatibility concerns.