The epidural is a common method of pain relief, particularly for childbirth, involving the delivery of medication into a specific area of the spine. This procedure is a type of regional anesthesia that uses a small catheter to administer local anesthetic drugs into the epidural space. This space is located just outside the dura mater, the tough membrane that surrounds the spinal cord. Tracing the origins of this practice requires examining the first attempts at chemically blocking nerve sensation.
The Genesis of Regional Anesthesia
The foundation for epidural anesthesia was laid in the late 19th century with the discovery of effective local anesthetics. In 1884, Austrian ophthalmologist Karl Köller demonstrated the anesthetic properties of cocaine, a compound isolated decades earlier, by using it to numb the eye for surgery. This breakthrough quickly led to experiments with blocking pain in other parts of the body.
In 1885, American neurologist James Leonard Corning performed a landmark injection of cocaine between the lower vertebrae of a human subject. Corning intended to inject the drug into the cerebrospinal fluid, a procedure now known as spinal anesthesia. However, based on the slow onset and limited spread of the anesthetic effect, his injection is widely believed to have inadvertently reached the epidural space instead.
Corning’s experiment constitutes the earliest recorded instance of an epidural block, placing the technique’s conceptual birth in the late 1880s. The first successful and intentional spinal block was achieved slightly later in 1898 by German surgeon August Bier. These early attempts demonstrated the potential of neuraxial blockade—injecting anesthetic near the central nervous system—and paved the way for the purposeful development of the epidural technique.
The Discovery and Early Application of Epidural Space
The first purposeful and documented injections into the epidural space occurred in 1901, marking the official beginning of epidural anesthesia as a distinct clinical practice. This breakthrough was achieved independently by two French physicians, Jean-Athanase Sicard and Fernand Cathelin. They described injecting local anesthetic agents into the caudal end of the epidural space through the sacral hiatus, an opening near the tailbone.
This initial approach, known as the caudal block, was first used to treat conditions such as sciatica and lumbago. Physicians preferred the epidural route because it avoided the side effects associated with the high doses of cocaine used in early spinal anesthesia. The technique for accessing the epidural space at the lumbar level, the location used for most modern epidurals, was later refined.
In 1921, Spanish military surgeon Fidel Pagés Miravé published the first report of successful lumbar epidural anesthesia. A significant technical advance followed in the 1930s when Italian physician Achille Mario Dogliotti described the “loss of resistance” method. This reliable technique, still used today, involves a syringe connected to the needle, where a sudden loss of resistance is felt when the needle tip passes through the tough ligament and enters the soft epidural space.
Transformation into Modern Obstetric Practice
The transition of the epidural from a surgical tool to a standard labor pain management procedure began in the mid-20th century. One of the first applications in obstetrics was reported in 1931 when Romanian obstetrician Eugene Aburel used a silk catheter to administer local anesthetics for labor analgesia. However, the technique remained complex and rarely used until further innovations improved safety and efficacy.
A major leap came with the introduction of continuous infusion methods in the late 1940s. Cuban anesthesiologist Manuel Martinez Curbelo reported the first successful continuous lumbar epidural in 1949. This technique allowed for prolonged pain relief rather than a single-shot duration.
This was made possible by threading a flexible catheter through the needle into the epidural space, a practice that became safer and more reliable with specialized equipment. The design of the Tuohy needle, introduced around the same time, was instrumental in this evolution by featuring a curved tip that helped guide the catheter more reliably. Modern practice now heavily relies on patient-controlled epidural analgesia (PCEA), which allows the patient to self-administer small, programmed doses. These refined delivery methods have cemented the epidural’s role as the most effective form of pain relief for labor today.