Undergoing Epidural Anesthesia and Analgesia

This article explains what to expect if you choose to have an epidural for pain relief during and after your operation.

 

What is an Epidural? And what is epidural analgesia?

An epidural is a fine, flexible tube (catheter) placed in the back near the nerves coming from the spinal cord, through which pain-killing drugs can be given to give pain relief. It is used during surgery (usually in addition to a general anesthetic or a spinal anesthetic) and after the operation for pain control.

When local anesthetics and sometimes other pain-relieving drugs, are put through the epidural catheter, messages to the nerve are blocked giving you pain relief. This effect leads to a decrease in the doses of painkillers given intravenously.

An epidural infusion pump is used to give pain-relieving drugs continuously through the epidural catheter. The pain relief lasts as long as the pump is running. When it is stopped, full feeling returns within a few hours.

 

What are the advantages of having an epidural?

• You get better pain relief than with other methods especially when you breathe deeply or cough or move around in bed.
• You should also need less amounts of other strong pain killers like NSAIDs (Voveran) and opioids (fentanyl, morphine). So, your breathing will be better, there should be less nausea & vomiting and you will likely be more alert.
• There is a reduced risk of certain surgical complications like blood clots in legs or lug & chest infection.
• There is also a possibility that you may lose less blood during surgery with an epidural, which means that the chances of needing a blood transfusion also decrease.

 

What if I don’t want an epidural?

It is your choice. Your anesthesiologist will let you know when they especially recommend an epidural. They will also tell you about alternative options available.

These alternatives include:

• Strong pain relief medications. g., Opioids like morphine and fentanyl
• A nerve /nerve plexus block. This is another way to give a local anesthetic.

 

Who cannot receive an epidural?

An epidural may not be possible for you, if

• You take blood-thinning drugs, such as warfarin/ clopidogrel & they have not been stopped (& an alternative started if needed) in time.
• Your blood does not clot properly e.g. clotting factor deficiencies.
• You’re allergic to local anesthetics
• You have significant deformity of the spine
• You have an infection in your back or widespread infection within your body
• You have previously had spinal surgery with metal implants in your back
• You have had problems with a spinal anesthetic or epidural in the past.

 

How is the epidural performed?

In the operation theatre, you will be hooked up to the monitors and an IV drip will be started.

Then you will be helped into sitting up on the OT table with your legs on a low stool or lying on your side with your legs tucked up towards your chest. You will be
helped to bend forwards, curving your back as much as you can. You will be requested to relax and leave your body loose.

Your anesthesiologist will scrub up and wear sterile attire. They will then clean your back with an antiseptic solution (can feel cold) and cover it with a sterile sheet.

The skin over the injection site and the anticipated path of the epidural needle will be infiltrated with a local anesthetic to make it numb. This may sting a little.

As the epidural needle and catheter are inserted, the feeling of pushing maybe there, which can be a bit uncomfortable. You will need to be still for this to be done. Once the catheter is in position the needle is removed and the catheter fixed onto your skin. The anesthetic team will explain what is happening and you will be aware of what is going on.

Sometimes a sharp electric shock like feeling, is experienced. If this happens, your anaesthetist may ask you where you felt it.

A sensation of warmth and numbness gradually develops after the local anesthetic is given.

When your epidural is in your lower back, your legs may feel heavy & become difficult to move.

Most people find the effects of an epidural to be a bit strange but not unpleasant. Feeling
and movement will return to normal when the epidural is stopped.

Side Effects and Complications

As with all anesthetic techniques, the possibility of unwanted side effects or complications exists with an epidural.

Very common side effects

Low blood pressure: it is normal for blood pressure to fall after an epidural. IV fluids and some drugs are used to correct this.

Inability to pass urine: if the nerves to the bladder are affected, this may happen. A urine catheter maybe needed to drain the bladder.

Itching: some drugs used with an epidural cause itching. Anti-histamines and changing the epidural drugs usually help.

Feeling sick (nausea & vomiting): generally happens less than with other anesthetic techniques. Responds to anti-sickness medicines.

Inadequate pain relief: sometimes the epidural may not completely relive your pain. Your anesthesiologist will decide how to improve the pain relief and whether you need to switch to another pain relief method.

Common side effects:

Headache (Post Dural Puncture Headache, PDPH): After about 1 in 100 epidurals, a severe persistent headache may develop. It happens if the needle used to place the epidural or the epidural catheter unintentionally puncture the bag of cerebrospinal fluid that bathes the spinal cord. A small amount of fluid leaks out, causing a headache. The headache is worse if you sit up and is relieved by lying flat. It may be accompanied by loss of hearing or muffling or distortion of hearing and a sensitivity to light. The headache usually will go away on its own with good hydration and pain relief in a few days. if it persists specific treatment is required.

Uncommon side effects and complications

Slow breathing: some drugs may cause this and needs treatment

Temporary nerve damage: uncommon, usually resolves in a few days, weeks or months

Rare or very rare complications

Permanent nerve injury occurs in 1 in 23,500 to 50,500 spinal or epidural injections

Paraplegia or death occurs in 1 in 54,500 to 1 in 141,500 spinal or epidural injections.

Catheter infection: An infection can occasionally develop around the epidural catheter. If this happens, it will be removed. It is rare for the infection to spread deeper than the skin. Antibiotics may be necessary or, rarely, emergency back surgery. Disabling nerve damage due to an epidural abscess is very rare.

Other complications: Convulsions (fits), severe breathing difficulty, permanent paraplegia (loss of use of one or more limbs) or death are very rare.

If you want more details about having a epidural, you can speak to our anesthesiologists any time.