Aim: Overview of recent knowledge about risks and benefits of blood transfusion. Type of study: Review article. Setting: Department of Anaesthesiology and Intensive Care, University Hospital, Ostrava. Methods: Summary of previously published data. Conclusion: Transfusion of blood and blood products remains controversial in clinical practice. Neither indication and timing nor benefit of this procedure is clearly determined. Previously often reported complications as blood-group incompatibility and infection are less frequent now, and new transfusion’s side effects as TRIM (transfusion-related immunomodulation) and TRALI (transfusion-related lung injury) are reported with growing evidence. This risk (often underestimated in the past) is discussed in the article, and compared with blood transfusion benefits. Either restrictive or more open approach to blood transfusion are supported as well as criticised by different groups of clinicians and „good clinical practice“ definition remains open for the future.

        Key words: blood transfusion, transfusion-related immunomodulation, transfusion-related lung injury