The epidural as we know it was first described in 1921 by Fidel Pagés, a Spanish military surgeon who published a technique for injecting anesthetic into the lumbar epidural space. But that single date undersells the story. The epidural did not spring from one person’s eureka moment; it emerged across decades from a chain of discoveries in local anesthesia, spinal injection, and catheter design, each building on the last. The version used in hospitals today bears only a loose resemblance to what Pagés performed over a century ago.
How Local Anesthesia Made Everything Possible
Before anyone could block pain by injecting drugs near the spine, someone had to discover that drugs could block pain at all. That happened in 1884, when Carl Koller, a young ophthalmologist in Vienna, demonstrated that a cocaine solution applied to the surface of the eye produced complete insensibility to pain.1PubMed. Carl Koller, cocaine, and local anesthesia: some less known and forgotten facts Koller had tested the drug in animal experiments and on himself before presenting it publicly, and the demonstration electrified the surgical world.2PubMed. From the legacy of Carl Koller. Notations on his experiments with cocaine Within months, surgeons across Europe were experimenting with cocaine solutions for everything from tooth extractions to limb surgery. The idea that you could numb a specific part of the body without rendering the patient unconscious was genuinely new, and it opened the door to injecting anesthetics closer and closer to the spinal cord.
Spinal Anesthesia Arrives
The logical next step was to inject cocaine directly into the fluid surrounding the spinal cord, blocking sensation across entire regions of the body at once. August Bier, a German surgeon, is credited with performing the first spinal anesthetic on August 16, 1898. He published his results the following year, describing six patients who underwent surgery under spinal anesthesia.3International Congress Series. The early history of spinal anesthesia Bier’s technique involved puncturing the membrane that encloses the spinal fluid and injecting cocaine directly into it. The approach worked dramatically well but came with side effects, including severe headaches that Bier himself experienced after a self-experiment on his own spine.
Spinal anesthesia and epidural anesthesia are often confused, but they target different anatomical spaces. A spinal injection goes through the tough membrane called the dura and delivers drug into the cerebrospinal fluid itself. An epidural stays outside the dura, depositing drug in the fatty tissue surrounding the spinal cord’s protective layers. This difference matters because epidurals tend to have a slower onset, can be topped up through a catheter, and carry a lower risk of the post-puncture headaches that plagued Bier’s early spinal technique. Bier’s work in 1898 was not an epidural, but it proved that regional anesthesia of the lower body was achievable, and it directly inspired the surgeons who would develop the epidural over the following two decades.
Fidel Pagés and the Birth of the Epidural in 1921
The first person to describe deliberately placing an anesthetic into the thoracolumbar epidural space in a human patient was Fidel Pagés Miravé, a Spanish military surgeon. In 1921, he published an article titled “Anestesia Metamérica” in the Revista Española de CirugÃa, laying out a technique for what he called “metameric anesthesia,” which we now recognize as single-shot lumbar epidural anesthesia.4PubMed Central. Overcoming Obstacles: The Legacy of Fidel Pagés, Founder of the Epidural, 100 Years After His Passing Pagés had studied the earlier intradural work of Bier and the French surgeon Tuffier, as well as sacral techniques developed by the Spanish urologist Gil Vernet in 1917 and 1918, and he synthesized these influences into something new.5PubMed. Centenary of epidural anaesthesia
Pagés’s story is one of the more bittersweet episodes in medical history. He died in a car accident in 1923, at just 37, only two years after his landmark publication.4PubMed Central. Overcoming Obstacles: The Legacy of Fidel Pagés, Founder of the Epidural, 100 Years After His Passing Because he published in a Spanish surgical journal rather than in one of the major international anesthesia journals, his contribution was slow to gain recognition. An Italian surgeon, Achille Mario Dogliotti, independently described a similar lumbar epidural technique about a decade later and received much of the initial credit in the wider medical community. Only in recent decades has Pagés been widely acknowledged as the originator.
From a Single Shot to a Continuous Catheter
Pagés’s original technique was a one-time injection. The anesthesiologist placed the drug, and when it wore off, the procedure was over. This limited how long a surgery could last and meant there was no way to fine-tune pain relief after the initial dose. The breakthrough that transformed the epidural from a short-lived block into something flexible enough for labor and lengthy operations was the insertion of a catheter, a thin tube left in place so that additional drug could be delivered as needed.
That innovation is credited to Manuel MartÃnez Curbelo, a Cuban anesthesiologist. On January 13, 1947, at the Hospital Municipal de la Havana, Curbelo threaded a catheter into the lumbar epidural space of a 40-year-old woman who was about to undergo surgery for a large ovarian cyst.6Bulletin of Anesthesia History. Manuel Martinez Curbelo And Continuous Lumbar Epidural Anesthesia The catheter allowed him to keep injecting small amounts of anesthetic throughout the procedure. Curbelo adapted a fine ureteral catheter for the purpose, and while early versions were crude by today’s standards, the concept was transformative. Continuous epidural anesthesia meant the technique could be extended for hours, a feature that would prove essential once epidurals moved into the labor ward.
How the Drugs Evolved Alongside the Technique
The hardware was only half the story. The anesthetic agents injected through an epidural catheter underwent their own dramatic evolution. The earliest local anesthetics were all derivatives of cocaine, and while they worked, they carried serious risks of toxicity affecting the brain and heart. Between the late 1800s and the 1970s, chemists developed a succession of synthetic alternatives, including procaine, lidocaine, and eventually bupivacaine, each designed to last longer or cause fewer dangerous side effects.7PubMed. From cocaine to ropivacaine: the history of local anesthetic drugs
Bupivacaine deserves special mention because it became the workhorse drug for epidurals during childbirth. Synthesized in 1957 and introduced to the market in 1965, it offered a long duration of action that was ideal for labor. But cumulative reports of cardiovascular toxicity, including rare cardiac arrests at high doses, eventually led to restrictions on how much could be given in a single injection.7PubMed. From cocaine to ropivacaine: the history of local anesthetic drugs Ropivacaine, developed later, offered a similar profile with a better safety margin. Today, labor epidurals typically use very dilute concentrations of these long-acting drugs, often combined with small doses of opioids like fentanyl, to provide pain relief while keeping motor function as intact as possible.
Epidurals Enter the Labor Ward
Epidurals were used in surgical settings for decades before they became routine for childbirth. Caudal epidural analgesia, where the injection enters through the small opening at the base of the sacrum rather than between the lumbar vertebrae, was actually explored for obstetric use as early as the 1940s. But the technique was finicky and unreliable. It was the lumbar epidural, placed higher on the spine with a catheter for continuous dosing, that eventually became the standard approach for labor pain.
By the 1960s, epidural analgesia was gaining popularity in maternity units across the developed world. The timing was not coincidental. Anesthesiologists had by then acquired decades of experience with continuous catheter techniques, the drug options had improved, and there was a cultural appetite for making childbirth less painful. Over the following decades, the concentrations of local anesthetic used during labor dropped substantially. Where earlier protocols relied on relatively strong concentrations that often left the lower body nearly paralyzed, modern formulations use much more dilute mixtures, sometimes as low as 0.0625% to 0.125% bupivacaine.8Indian Journal of Pain. Labor epidural analgesia: Past, present and future These lower doses allow many women to retain enough leg strength to shift positions in bed or even walk, a development that gave rise to the term “walking epidural.”
The Walking Epidural and Combined Spinal-Epidural
The walking epidural was a response to one of the most common complaints about traditional labor epidurals: the heavy, numb feeling in the legs that confined women to bed. By reducing the concentration of local anesthetic and relying more on small opioid doses delivered to the epidural space, clinicians found they could maintain good pain relief with far less motor blockade. The term “walking epidural” was originally coined for a combined spinal-epidural (CSE) technique that used a low-dose opioid injected into the spinal fluid for rapid onset, with an epidural catheter left in place for ongoing top-ups.8Indian Journal of Pain. Labor epidural analgesia: Past, present and future
The combined spinal-epidural itself represents a merging of the two techniques that had developed in parallel since the late 1800s. A CSE block gives the fast, dense pain relief of a spinal injection together with the flexibility of a continuous epidural catheter, allowing clinicians to extend and adjust analgesia for as long as labor lasts.9PubMed. The combined spinal-epidural technique In practice, many labor wards now offer either a standard low-dose epidural or a CSE depending on the clinical situation, and the distinction between them has blurred as drug concentrations have converged.
Letting the Patient Control the Dose
One of the more significant recent changes in how epidurals are managed during labor has been the shift from a fixed continuous drip to patient-controlled epidural analgesia, or PCEA. The concept entered clinical practice around 1988, and it works much like a patient-controlled morphine pump: a baseline infusion runs in the background, but the patient can press a button to deliver an additional small bolus when pain increases.10PubMed. Patient-controlled epidural analgesia for labor
Early studies comparing PCEA with continuous infusion found that women who controlled their own top-ups used significantly less total anesthetic. One of the first randomized trials reported that PCEA patients received roughly 11 mg of bupivacaine per hour compared with about 15 mg per hour in the continuous-infusion group, with similar pain relief and high satisfaction scores.11PubMed. A comparative study of patient controlled epidural analgesia (PCEA) and continuous infusion epidural analgesia (CIEA) during labour Later research confirmed the pattern: demand-dose-only PCEA resulted in less total drug without worsening pain scores, motor block, labor duration, or outcomes for mother and baby.12PubMed. Epidural labor analgesia: continuous infusion versus patient-controlled epidural analgesia with background infusion versus without a background infusion Beyond the pharmacological benefits, women consistently reported appreciating the sense of control, saying it reduced their reliance on clinical staff and made them feel more involved in managing their own labor.
Finding the Epidural Space
One quirk of epidural placement that has stayed remarkably consistent over the decades is the technique used to confirm that the needle tip has reached the right spot. The epidural space is identified by feel: the anesthesiologist advances a needle while applying gentle pressure to a syringe and waits for a sudden drop in resistance, which signals that the needle has passed through the tough ligament and entered the epidural space. This “loss of resistance” method has been debated for decades, mainly over whether to use air or saline in the syringe. Saline tends to produce a crisper sensation of the plunger giving way, but air has its own advocates.13PubMed Central. Air versus saline in the loss of resistance technique for identification of the epidural space A Cochrane review found that the ideal technique remains unclear, and in practice the choice still comes down to the individual anesthesiologist’s training and preference. It is a reminder that even in an era of ultrasound guidance and computerized pumps, some parts of regional anesthesia remain stubbornly craft-based.
Safety Checks and the Test Dose
One of the persistent risks of epidural placement is that the catheter can end up somewhere it should not be, either inside a blood vessel or through the dura into the spinal fluid. In either case, injecting a full dose of anesthetic could cause serious harm. To guard against this, anesthesiologists developed the concept of a “test dose,” a small initial injection designed to reveal misplacement before a large volume of drug is given.
The standard test dose historically contained a small amount of epinephrine, usually 15 micrograms. If the catheter had accidentally entered a blood vessel, the epinephrine would cause a noticeable spike in heart rate or blood pressure, alerting the clinician to reposition. Research has shown that this test is reliable under most circumstances but not foolproof. During general anesthesia, for instance, the hemodynamic response to 15 micrograms of epinephrine can be blunted enough that misplacement goes undetected.14PubMed. Hemodynamic responses to intravascular injection of epinephrine-containing epidural test doses in adults during general anesthesia In pregnant patients, an alternative approach uses 100 micrograms of fentanyl, because the resulting drowsiness or dizziness within five minutes is a more reliable signal of intravascular injection in that population.15PubMed. The epidural test dose: a review These population-specific protocols developed over time as case reports and clinical trials revealed the limitations of a one-size-fits-all test dose.
Epidurals Beyond Childbirth
While labor analgesia is the context most people associate with epidurals, the technique has a broad life outside obstetrics. Epidural anesthesia is used for a wide range of surgeries on the lower body, from hernia repairs to hip replacements. In some surgical settings it offers advantages over general anesthesia. A study comparing epidural and general anesthesia for outpatient hernia repair found that patients who received an epidural were far less likely to need treatment for nausea afterward, with roughly 9% requiring intervention compared with 37% of those under general anesthesia. Complaints of postoperative pain were also lower in the epidural group.16PubMed Central. A comparison of epidural versus general anesthesia for outpatient endoscopic preperitoneal herniorrhaphy
Epidural injections also play a role in chronic pain management, particularly for sciatica and other forms of nerve-related leg pain. Beginning in the early 1950s, clinicians started injecting corticosteroids into the epidural space to reduce inflammation around irritated spinal nerve roots.17PubMed. The Epidural Treatment of Sciatica: Its Origin and Evolution Since the 1970s, numerous clinical trials have examined whether these epidural steroid injections actually work. The evidence suggests a real but modest benefit for leg pain in the short term, and their widespread use remains somewhat controversial among pain specialists who debate whether the effect is large enough to justify the procedure’s cost and risks.
The Feminist Debate Over Labor Pain Relief
The spread of labor epidurals in the 1960s and 1970s did not happen in a cultural vacuum. Pain relief in childbirth has been politically charged for centuries, and the epidural landed squarely in the middle of a feminist disagreement that continues in softer forms today. Earlier waves of feminists had fought hard for women’s right to receive anesthesia during labor, pushing back against religious and medical establishments that either denied pain existed or argued that women should endure it. But as epidural analgesia became more common, a second wave of feminists took the opposite position, arguing for a return to non-medicalized, female-controlled “natural” childbirth and, in some cases, framing the pain of labor as an empowering experience that the epidural stripped away.18PubMed. Pain relief in childbirth: changing historical and feminist perspectives
This tension persists, though the terms of the debate have shifted. Today the argument is less about whether epidurals should exist and more about whether their availability creates subtle pressure on women to accept them, or conversely, whether the “natural birth” movement creates guilt for women who want pain relief. The epidural occupies a strange cultural space: it is simultaneously the most requested medical intervention in childbirth and one of the most debated. Whatever side of the conversation you land on, the technical history is clear. What began as a single experimental injection by a Spanish military surgeon in 1921 has become one of the most refined and widely used procedures in modern medicine, shaped by more than a century of incremental innovation in needles, catheters, drugs, and the evolving expectations of the patients who receive them.