When monitoring a person in shock, what should be controlled?

In the context of monitoring a person in shock, controlling external bleeding is crucial because it directly impacts the body's ability to maintain blood volume and pressure. Shock occurs when there is inadequate blood flow to the organs and tissues, often due to loss of blood or fluids. External bleeding can exacerbate shock by further diminishing the volume of circulating blood, leading to decreased oxygen delivery to vital organs.

While blood pressure, internal bleeding, and heart rate are all important factors in the overall assessment and management of a patient in shock, they are secondary to the immediate need to control any visible external bleeding. By addressing external bleeding first—through direct pressure, elevation, or other appropriate methods—you can help stabilize the patient's condition and potentially reverse the course of shock.

Thus, managing external bleeding is a priority in the treatment of shock, making it the most relevant choice in this scenario.