About one third of injury deaths are due to shock from blood loss. Preventing shock in people with uncontrolled bleeding is, therefore, very important and is generally done by giving fluids intravenously. The aim is to maintain blood pressure and reduce tissue damage. The composition of these fluids can vary, and there have been systematic reviews comparing different fluid types, but the volume of fluid given and the time at which it is given can also vary. It not yet clear which timing and which volume are the most effective. The authors searched for relevant medical research reports and found six randomised controlled trials involving a total of 2128 people. In each study, people with uncontrolled bleeding were randomly assigned to receive one treatment or another. Three studies were about the amount of fluid given (more or less), and three studies were about giving fluid at different times following injury (sooner or later). The authors were interested in finding out which treatments were better, to reduce deaths and to enable blood clotting. Blood clotting was measured by prothrombin time and partial thromboplastin time during fluid administration. The review of trials found that there is uncertainty about the best time to give fluid and what volume of fluid should be given. While increasing fluids will maintain blood pressure, it may also worsen bleeding by diluting clotting factors in the blood. The first version of this review was published in 2000 and included these six trials. The authors searched for new, relevant studies in 2003, 2008 and 2014 but none were found. The authors will look for studies in 2020, and any new information will be incorporated into the review.