Emergency Medical Technician (EMT) Trauma Practice Test

In a patient with hemophilia, which is a disorder that impairs the blood's ability to clot normally, applying a tourniquet above the laceration is the most appropriate first step. This is because hemophiliac patients are at a higher risk of significant bleeding and prolonged bleeding times due to the lack of clotting factors in their blood. By applying a tourniquet, it can help control and minimize the bleeding from the laceration. The other options, such as initiating high-flow oxygen therapy, placing direct pressure on the laceration site, or starting an IV line for fluid replacement, are not the most appropriate initial steps for a patient with hemophilia who is actively bleeding.