 This clinical trial will evaluate the ease of conducting a randomized trial on patients with severe head injury who are cared for by paramedics in the out of hospital setting. The trial will compare two different kinds of fluids that are commonly used to elevate blood pressure and minimize the impact of the brain injury. The two solutions are a salt solution of different concentrations. One is a normal saline solution similar to the consistency of human blood and the other is a higher concentration mixed with a sugar that helps to keep the solution in the blood stream longer. This study is conducted without patient consent at the time of the study enrolment. The study will report on whether this trial is feasible in the out of hospital setting before launching into a larger definitive trial. 