Objectives: The aim of this study was to investigate the proportion of patients with massive bleeding due to trauma in relation to patients with other causes of massive bleeding, to examine the proportion of patients treated proactively, to compare the mortality in the first 48 hours in the group treated proactively with the conventional treatment. Finally, the aim was to compare the mortality rate of patients treated proactively or conventionally with regards to the age and sex. Study outline: Retrospective study Participants and methods: Subjects were treated for massive bleeding at Clinical Hospital Centre Osijek from 1st January 2015 to 31st May 2016. They received 10 and >10 doses of blood products within 24 hours via transfusion. The data on respondents were collected from the transfusion database, while data on patients’ characteristics and the outcome of the treatment were taken from patients’ medical history records. Results: The study included 45 patients, the most of them were elderly men (66.7%), with median age of 63 years. Only 4 out of 45 patients were reported to have trauma as the cause of massive bleeding. Respondents were divided into two groups according to the treatment they received – proactive (62.2%) and conventional (37%) treatment. The mortality rate of patients treated proactively was 53.6% and of those treated conventionally 41.2%. Based on the sum of received blood products in 24 hours, it can be concluded that more patients were treated conventionally. Conclusion: Trauma is not the most common cause of massive bleeding. Higher number of patients at Clinical Hospital Centre Osijek was treated proactively. By the sum of received blood products, the conventional treatment prevails. The mortality rate of patients treated proactively is higher. The introduction of new guidelines for the treatment of massive bleeding slowly affects local transfusion therapy. Due to the small number of respondents and parameters studied, based on the obtained results, we cannot determine the advantage and benefits of either of the procedures observed in comparison to one another.