[HYPNOS and Revista Española de Anestesiología y Reanimación, history of a coexistence relationship].

The year 2003 will mark the fiftieth anniversary of the publication of Revista Española de Anestesiología y Reanimación (Spanish Journal of Anesthesiology and Postoperative Recovery). For that reason, it is appropriate to explore some of the details of the journal's early history. In 1954 and 1955 two official journals of anesthesiology co-existed in Spain: Revista Española de Anestesiología, which was the official organ of the Spanish Society of Anesthesiology and Postoperative Recovery, and Hypnos, which was the bulletin of the Association of Anesthesia of the Academy of Medical Sciences of Barcelona. The two publications merged in 1956 as Revista Española de Anestesiología, thereby forming the journal whose name eventually became Revista Española de Anestesiología y Reanimación.