Bleeding resuscitation in the ambulance service, an observational study of standard care in Sweden

Background: The ambulance service in Sweden has most often only crystalloids as resuscitation, even though restrictive use of clear fluids in bleeding patients is recommended. The aim of this study was to describe the treatment and outcome of bleeding patients treated by the ambulance service.Methods: This was a prospective observational multi-center study. Ambulance organizations in six different regions were invited to participate, each of them for a period of six months. Adult bleeding patients where fluid resuscitation with crystalloids was initiated by the ambulance service was consecutively included. Prehospital data on type of bleeding, mechanism and severity of injury, vital signs, estimated bleeding volume, treatment and transport time was collected from the ambulance service. Results from laboratory tests and data of transfusion requirements and mortality were obtained from the medical records, after hospital admission.Results: 181 patients were resuscitated with crystalloid fluids by the ambulance service and were included in the study. Gastrointestinal bleeding was the cause of fluid resuscitation in 48% of the patients and bleeding due to trauma in 23%. A high proportion of the patients (41%) had a coagulopathy upon admission at the hospital, defined as prothrombin time > 1,2, platelet count < 150 x 10(9)/L and/or activated prothrombin time > 32 s. Shock Index (SI) was 1.2 (mean) (SD 0.4). The mean volume of crystalloid fluids administered was 626 mL (SD 366), with one third of the patients receiving 1000 mL or more. Tranexamic acid was administered to 28% of the patients. Blood transfusions were given to 50% of the patients upon hospital admission. SI more than 1.3 predicted need of blood transfusions and bleeding > 500 mL predicted increased 24 h mortality. The overall 24-hour mortality was 7.2% and in patients with blood loss greater than 500 mL, the mortality rate was 12.1%.Conclusion: In this study gastrointestinal bleeding and trauma were the leading causes of severe prehospital bleeding. Blood loss over 500 mL and Shock Index above 1.3 were key predictors of poor outcome, highlighting the potential benefit of earlier blood product administration.