[Centenary of spinal anesthesia in Spain: first steps (1899-1904)].

With the aim of commemorating the centennial of the first spinal anesthesia in Spain, we review the process followed during the early phase of application of the technique, the period associated with spinal injection of cocaine, which was the only anesthetic agent used. We describe the first trials, the influence of the Paris Congress of 1900 in spreading interest in the technique, the varied degree of acceptance by Spanish authors, and the gradual uneasiness with the procedure that arose as a result of accidents. A look at reports by Pi Sunyer and Raventós concerning possible toxic effects on the central nervous system close this overview of the earliest times of spinal anesthesia in Spain.