Epidurals provide excellent pain relief for women during labor and delivery. They are also a useful form of anesthetic for operations in the legs, pelvis or abdomen, and can be continued afterward for postoperative pain control. Epidurals involve inserting a needle, often along with a thin tube, into the epidural space near the spinal cord. Although this might sound risky, epidurals are generally very safe. There is a small risk of complications occurring around the time of epidural insertion and an even smaller likelihood of long-term side effects. Possible long-term effects include minor or, very rarely, major neurologic symptoms.
Minor Neurologic Symptoms
Occasionally, a person will notice numbness, tingling or weakness in a small area that persists after an epidural has worn off. This may represent damage to a nerve caused by contact with the epidural needle or the thin tube called an epidural catheter. The true frequency of minor neurologic symptoms after an epidural is unknown. But when they do occur, these symptoms are more commonly caused by factors unrelated to the epidural, such as pressure on nerves in the pelvis as a baby is being born or compression of nerves due to maintaining certain body positions for a long time during surgery. There is no treatment for these minor neurologic symptoms, but they usually resolve on their own within a few months.
Major Neurologic Symptoms
Rarely, major neurologic symptoms occur after an epidural. They may include weakness or paralysis, loss of sensation over more than a small area, or changes in bowel or bladder function. These symptoms are caused by very uncommon complications, such as bleeding or infection in the epidural space, causing an epidural hematoma or abscess. Pressure from the accumulation of blood or pus damages the spinal cord and surrounding nerves.
Epidural hematomas can be caused by an epidural needle or catheter puncturing a blood vessel. Epidural abscesses can occur when bacteria enter the space during epidural insertion or while the catheter is in place. With prompt treatment, long-term neurologic symptoms may be minimized or prevented. According to an August 2012 review article in "Neurologic Clinics," epidural hematomas occur in approximately 1 in 150,000 women receiving an epidural for labor, delivery or cesarean section. Epidural abscesses occur in about 1 in 500,000 women receiving an epidural for obstetrical reasons and 1 in 1,000 to 1 in 100,000 people receiving an epidural for non-obstetrical surgery.
Back pain may occasionally occur if many attempts are required to insert an epidural. The resulting tissue irritation can cause pain around the insertion site for a few days. However, most back pain after an epidural is due to other factors, such as being pregnant, delivering and caring for a newborn, or maintaining the same position for a prolonged time during surgery. Indeed, a landmark study published in "Anesthesiology" in July 1994 reported that back pain was present 1 to 2 months after delivery in 44 percent of women who received an epidural and 45 percent of those who did not. Based on this and subsequent research, the consensus among experts is that an epidural does not cause long-term back pain.
Reducing the Risks
The risk of an epidural hematoma is increased if your ability to form blood clots is reduced due to a bleeding disorder or use of blood-thinning medication. The risk of an epidural abscess is higher if your ability to fight infections is impaired, which can occur with conditions like HIV/AIDS or use of certain medications, such as steroids or those used after an organ transplant. So if you are considering having an epidural, discuss all your medical conditions with your anesthesiologist, and be sure to mention whether you bleed or bruise easily or are unusually susceptible to getting infections. Also report all prescription and over-the-counter medications and supplements you are taking, as some may interfere with clotting or your immune system.
Seeking Medical Attention
If you recently had an epidural or still have an epidural catheter in place, tell your doctor immediately if you notice any new or increasing neurologic symptoms, such as weakness in your legs, numbness or tingling in more than a small area, or changes in bowel or bladder function. These may represent an epidural hematoma or abscess that requires immediate treatment. With an epidural hematoma, these symptoms usually occur abruptly and worsen rapidly. With an epidural abscess, they develop more slowly and may not be noticed until several days after an epidural is inserted. They are usually accompanied by a fever and pain and inflammation at the epidural insertion site, and these conditions often occur before the neurologic symptoms. Therefore, also notify your doctor immediately if you notice any of these non-neurologic symptoms.
Reviewed by: Tina M. St. John, M.D.