The historical origins of modern international normalized ratio targets.

Prothrombin time (PT) and its derivative international normalized ratio (INR) are frequently ordered to assess the coagulation system. Plasma transfusion to treat incidentally abnormal PT/INR is a common practice with low biological plausibility and without credible evidence, yet INR targets appear in major clinical guidelines and account for the majority of plasma use at many institutions. In this article, we review the historical origins of INR targets.

Evaluating the appropriateness of platelet transfusions compared with evidence-based platelet guidelines: An audit of platelet transfusions at 57 hospitals.

Background: Platelet transfusions are used to prevent or control bleeding in patients with thrombocytopenia or platelet dysfunction. The pretransfusion platelet count threshold has been studied extensively in multiple patient settings yielding high-quality evidence that has been summarized in several comprehensive evidence-based platelet guidelines.

Study Design And Methods: A prospective 12-week audit of consecutive platelet transfusions using validated and evidence-based adjudication criteria was conducted.

Transfusion in the Spanish Civil War: Supply and demand, the role of the "blood transfusion officer" and British planning for the outbreak of the Second World War.

During the First World War blood transfusion progressed from being a rarely used treatment to a major component of the resuscitation of exsanguinated casualties, relying on local donation and availability of medical expertise. In the 1920s and early 1930s, clinical use of transfusion gradually increased supported by growing civilian, often volunteer, blood donor systems. The Spanish Civil War (1936-1939) introduced the first systematic use of aerial bombardment to intimidate the civilian population and to destroy infrastructure; it also saw more mobile battlefronts, replacing the relatively static trench warfare of 1914-1918.