Obstetrical Epidural Analgesia

What is an epidural?

An epidural is a regional anesthesia technique used in labor and delivery for the relief of labor pain.  Positioning of the patient during the procedure is very important to the success of an epidural.  Epidurals are placed with the patient lying on the side or in the sitting position.  The patient will be helped to assume the correct position.  An epidural is performed using sterile technique under local anesthesia at the injection site.  Once the skin is "numb" an epidural needle is passed between the spines of the lumbar vertebra to reach the epidural space.  This space is just outside the "spinal" space.  The "spinal" space contains the cerebrospinal fluid and the spinal nerves.  Local anesthetics are injected into the epidural space and this "numbs" the nerves that cause labor pain.  Most labor epidurals are made "continuous" by placing a tiny, soft tube or catheter into the epidural space through the needle.  This tube is secured to the patient's back with a sterile dressing.  Epidural analgesic medications are infused through this catheter to keep the patient comfortable during labor and delivery.  This continuous technique allows the epidural to be effective without "wearing off".

Does the epidural hurt?

Placement of an epidural for labor and delivery is done under local anesthesia.  The skin and underlying tissues are "numbed" and the epidural is performed in this anesthetized area.  Most patients experience a "sting" when the skin is anesthetized and some cramping in the back or hips when the epidural pain medicine is injected.  Most feel it is not more uncomfortable than having an intravenous infusion started and much less intense than a labor pain.  Some patients experience a paresthesia, or "intense tingle", down to the foot during placement of the epidural catheter.  This is very brief and normal.  The cause of this tingle is the brushing of a spinal nerve by the epidural catheter when it is placed.  This sensation may (or may not) occur and in both instances is normal.  Most patients find that epidural placement is not as uncomfortable as they anticipated. 

With an epidural what will I feel during labor?

Epidural analgesia for labor and delivery produces a "numb" sensation of the abdomen and legs.  The feeling is much like that experienced during dental analgesia, only in a different region of the body.  This numbness masks the discomfort of labor therefore allowing the patient relief from the pain of labor. While epidural analgesia has no major effect on awareness or mental functions, many patients are able to rest, and in some cases sleep, until it is time to push.  Many patients experience a pressure sensation with uterine contraction.  This is normal and in some cases preferred.

When can I have an epidural?

You should discuss epidural analgesia with your health care professional during your prenatal visits.  Generally, you may have epidural analgesia for labor and delivery when you are in a regular labor pattern and you and your health care professional feel you are ready.  You do not have to decide whether or not to have an epidural on arrival to the hospital.  Some patients who plan other methods of labor pain control, such as prepared childbirth or Lamaze, may change that plan as labor progresses.  A labor epidural may be done at that time.

Do epidural medications adversely affect the baby?

The medications used for labor epidural analgesia do not cause any significant effect on the baby.  The amount of medicine transmitted from the mother to the baby by the placenta does not cause any appreciable effect on the baby's Apgar scores or behavioral tests.  Epidural labor analgesia has been routinely used to treat labor pain for many decades and has a good safety record. 

Am I a good candidate for an epidural?

The vast majority of patients are good candidates for epidural analgesia for labor and delivery.  However certain conditions, if present, could possibly make performing an epidural problematic.  A partial list of common conditions are:

  • True allergy to the medications used in an epidural
  • A disorder of blood clotting or serious abnormal bleeding
  • Delivery of the infant is in progress
  • A serious spinal deformity or extensive surgery to the spine
  • Infection at the site of injection
  • Serious neurologic disease: tumors, deformity, etc.
  • Inability to cooperate with the procedure

If you have concerns about your ability to have an epidural to manage your labor pain control, you may wish to consult with your health care provider and if necessary seek consultation with our Anesthesiology Department prior to your due date.

What if I need a C-section?

In most cases with a labor epidural in place, the epidural can be reinforced with additional medicine injected through the epidural catheter to make the regional block stronger.  A C-section can usually be performed without an additional procedure.  C-section with epidural anesthesia is very common and regional anesthesia for surgical delivery of the baby is performed. If you are using prepared childbirth or Lamaze for pain control and a C-section is warranted, then an epidural or spinal block can be placed at that time. In rare cases, due to urgency of the C-section, you may require a general anesthetic.  Your obstetric health care provider and your Anesthesiologist will confer on this need and communicate it to you.  The Anesthesia Department is always prepared to perform a general anesthetic if required.

Is a spinal the same as an epidural?

No.  While the techniques may appear similar when observed, they differ in their indications, end points and in their results.  A spinal is described as placing a needle beyond the epidural space in the "spinal" space where the cerebrospinal fluid and spinal nerves are contained. Narcotics or local anesthetics are injected in this space.

Spinals are generally used for surgical indications.  While a C-section can be performed under a spinal, it is generally not used for labor analgesia unless it is used in concert with an epidural.  A spinal alone is generally not used as a continuous technique and thus has a limited time course.  Since labor is of an undetermined duration, a spinal may not last throughout the entire labor.  The exception is when a spinal is used as a "saddle block".  This is used at the end of labor then the baby is delivered. 

The obvious disadvantage is the patient has been in pain the majority of their labor experience. If a spinal is done with an epidural, the spinal is used for the first stage of labor when the discomfort from labor is not as severe.  The patient may consider it an advantage to have less numbness (and thus increased mobility) if only the narcotics are injected in the spinal portion of the procedure.  Once the patient enters the more painful stages of labor, the epidural is injected and used for the remainder of the labor. The combined technique has been used in some parts of the country.  However, due to the increased risk of post-dural puncture headache, slightly increased risk of a dysfunctional epidural (due to not being used immediately), and the short functional period for which the spinal narcotic is helpful, we do not recommend the combined technique to the vast majority of our laboring patients.

What are some problems with epidurals?

This section is not a substitute for informed consent for a labor epidural and is not exhaustively complete.  The purpose here is to discuss some general issues associated with labor epidurals.

Soreness at the site of injection

Like any other injection, this is usually normal. 

Chronic back pain

Generally not associated with labor epidurals.  The incidence of back pain in patients after delivery is similar for patients with and without epidurals.  In fact, epidural injections are used to treat chronic back pain disorders.

Spotty, "Hot Spot" or one sided epidurals

This does occur, but infrequently.  The factors involved are generally individual to the patient's anatomy, epidural catheter location and response to the medications.  Generally, problems with lack of adequate analgesia can be resolved by additional injections of medications through the epidural catheter or repositioning the catheter.  Rarely, an epidural will have to be replaced to provide proper analgesia.

Post-dural puncture headaches

This, again, is an uncommon complication of epidural analgesia.  The epidural needle is advanced to a space that is only a few millimeters in width.  Patient movement, difficult anatomy or an abnormally small space could cause the needle to nick or perforate the covering of the spinal space.  The resultant leak of cerebrospinal fluid will usually cause a headache.  Conservative treatments for this headache include:  hydration, rest, caffeine containing fluids, and many others.  The definitive treatment is to perform an "epidural blood patch".  This is extremely effective.  A blood patch is done by performing an epidural near or at the site of the previous perforation and injecting blood obtained from the patient into the epidural space.  The blood clots, and this seals the hole.  Performing a blood patch does not alter the patient's ability to have an epidural for subsequent deliveries.