Romanian surgeon Nicolae Racoviceanu-Pitești (1860–1942) was the first to use opioids for intrathecal analgesia; he presented his experience in Paris in 1901.
In 1921, Spanish military surgeon Fidel Pagés (18861923) developed the modern technique of lumbar epidural anesthesia, which was popularized in the 1930s by Italian surgery professor  (18971966). Dogliotti is known for describing a "loss-of-resistance" technique, involving constant application of pressure to the plunger of a syringe to identify the epidural space whilst advancing the Tuohy needle – a technique sometimes referred to as Dogliotti's principle. Eugen Bogdan Aburel (18991975) was a Romanian surgeon and obstetrician who in 1931 was the first to describe blocking the lumbar plexus during early labor, followed by a caudal epidural injection for the expulsion phase.
Beginning in October 1941, Robert Andrew Hingson (19131996), Waldo B. Edwards and James L. Southworth, working at the United States Marine Hospital at Stapleton, on Staten Island in New York, developed the technique of continuous caudal anesthesia. Hingson and Southworth first used this technique in an operation to remove the varicose veins of a Scottish merchant seaman. Rather than removing the caudal needle after the injection as was customary, the two surgeons experimented with a continuous caudal infusion of local anesthetic. Hingson then collaborated with Edwards, the chief obstetrician at the Marine Hospital, to study the use of continuous caudal anesthesia for analgesia during childbirth. Hingson and Edwards studied the caudal region to determine where a needle could be placed to deliver anesthetic agents safely to the spinal nerves without injecting them into the cerebrospinal fluid.
The first use of continuous caudal anesthesia in a laboring woman was on January 6, 1942, when the wife of a United States Coast Guard sailor was brought into the Marine Hospital for an emergency Caesarean section. Because the woman had rheumatic heart disease (heart failure following an episode of rheumatic fever during childhood), her doctors believed that she would not survive the stress of labor but they also felt that she would not tolerate general anesthesia due to her heart failure. With the use of continuous caudal anesthesia, the woman and her baby survived.
The first described placement of a lumbar epidural catheter was performed by Manuel Martínez Curbelo (5 June 19061 May 1962) on January 13, 1947. Curbelo, a Cuban anesthesiologist, introduced a 16 gauge Tuohy needle into the left flank of a 40-year-old woman with a large ovarian cyst. Through this needle, he introduced a 3.5 French ureteral catheter made of elastic silk into the lumbar epidural space. He then removed the needle, leaving the catheter in place and repeatedly injected 0.5% percaine (cinchocaine, also known as dibucaine) to achieve anesthesia. Curbelo presented his work on September 9, 1947, at the 22nd Joint Congress of the International Anesthesia Research Society and the International College of Anesthetists, in New York City.