1932

Evipal, sodium salt version of hexobarbital becomes the first barbiturate agent that induces anesthesia in surgical patients. In 1935, its successor, the thiobarbiturates (Thionembutal, with sodium salt version Pentothal) revolutionized intravenous anesthesia: “This agent rapidly displaced the rest of the barbiturates as an anesthetic, partly due to the swiftness of its onset and its short action period, and it currently remains the preferred intravenous anesthetic in many types of surgical intervention” (López-Munoz, 337).