Hospital  >  Departments  >  Anesthesia  >  Division of Obstetrical Anesthesia  >  Patient Information

Patient Education: Diseases Conditions Treatments & Procedures


Epidural Analgesia

This is a form of pain relief for women in labour provided by the anesthesiologist. Using a local anesthetic (the same medication used by the dentist to freeze the jaw), the nerves to the womb and birth canal are frozen by an injection in the lower back. A small dose of a morphine-like drug is often included to reduce the amount of freezing required. Epidural analgesia does not make you or your baby sleepy and can be used without slowing labour. In fact, labour may become more efficient once pain relief as been achieved. All patients receiving epidurals or spinals require an intravenous line in the arm or hand before the epidural is provided. The intravenous line is removed after delivery, and after the effects of the epidural have worn off.

The epidural space in the spine is located using a special needle, which is passed between the bones of the spine, 1 to 3 inches deep (2.5 to 7.5 cm) and about 6 inches (15 cm) above the tailbone. The nurse will help you get into the best position - either lying on your side or sitting - for the few minutes it takes to insert the epidural. After washing your lower back with antiseptic and freezing the skin, the needle is introduced into the epidural space. A thin, flexible tube (the epidural catheter) is passed through the needle, which is removed. Local anesthetic ("freezing") is injected through the tube to relieve labour pain. The epidural catheter is then secured with tape. At this time, nothing hard or sharp remains in your back.

It takes between 5 and 30 minutes for the epidural to work. During this early stage you will feel warmth, in your lower body as well as warmth and tingling in the legs, followed by pain relief. Although we use as little medication as we can to relieve the pain, some women will notice that their legs have become heavy. The initial dose of freezing may last up to two hours. To prevent the pain from returning, medication is given continuously through the catheter, using a computer-controlled syringe (also called patient controlled epidural). The patient partially controls the amount of medication she receives. If the pain returns in spite of continuous medication, additional doses can be given. When it is time to push with contractions, the dose of medication may be reduced to allow return of some feeling.

The epidural may cause loss of feeling and weakness in your legs. However, some patients require very little pain medicine and may be able to get out of bed (also called a "walking epidural"). Your nurse will test your leg function to determine whether or not this is possible for you. Most patients are able to change position in bed without assistance.

See also: epidural side effects and complications.

For more information about epidural analgesia for labour, please see the Division of Obstetrical Anesthesia.