Conditions & Treatments

Pain relief options (including epidural) for women in labour - What it is

What pain relief options are available?

Here is some information about the main pain relief methods available to labouring women in Singapore General Hospital. If you have not decided at the time of labour, you can seek advice from the midwife who is with you in the labour ward.

Entonox

Entonox is a gas made up of 50% nitrous oxide and 50% oxygen. It is sometimes known as “gas and air” or “the laughing gas”. You breathe Entonox through a mask or mouthpiece.
Your midwife will guide you through the technique of using Entonox during labour.

Benefits	Side effects /disadvantages
Acts within a few breaths and wears off in minutes	Light-headedness
Causes no harm to baby	Nausea & vomiting
Reduces pain intensity	Partial pain relief only
Can be used together with other pain relief	Partial pain relief only

Opioids

Opioids are painkillers such as pethidine.

Benefits	Side effects / complications
Can provide some pain relief	Drowsiness, nausea or vomiting
Can be given easily by midwives as an injection into a large muscle	May slow down your breathing
Acts after 30 min and the pain relief may last a few hours	May make your baby drowsy or slow to take their first breath. These effects are worse if the baby is born one to four hours after an injection of pethidine. This may mean that your baby may not suckle well in the first few hours or may need special care post-delivery. If necessary, your baby can be given an injection to lessen this side effect. Hence, it may not be possible to give you an opioid injection if you are too close to delivering your baby.

EPIDURALS

IF you have any questions, please ask the duty anaesthesiologist to explain further.

What are Epidurals?

The aim of an epidural is to reduce the intensity of labour pain.
These are carried out by an anaesthesiologist.
To initiate epidural pain relief, a needle is inserted into the lower part of your back, through which a catheter (a fine plastic tube) is placed near nerves in your spine. Painkillers are then given through this throughout labour.

What does having an epidural involve?

First, you will have an intravenous fluid drip commenced through a vein on your hand or arm.
You will be asked to sit bending forwards or curled up on your side, and your back will be cleaned with an antiseptic.
Some local anaesthetic will be injected onto the skin over the lower part of your back to reduce the pain of the epidural insertion.
The epidural needle will be inserted here. Through the needle, the catheter is put in, and the needle then removed, leaving the epidural catheter behind.
It is important to keep still while the epidural is being sited, but after the catheter is securely fastened, you are free to move.
Once the epidural catheter is in place, you will be given painkillers through it. It usually takes about 15 - 20 minutes to set up the epidural and 15 -20 minutes for the medication to work.
While the epidural is starting to work, your midwife will monitor your vital signs including blood pressure regularly and monitor your baby’s heart rate continuously.
During labour, you can have extra doses of painkillers through the epidural catheter either as a single injection (a top-up), a slow and steady flow using an infusion pump, or with a patient-controlled epidural analgesia (PCEA) pump.
You may require some adjustment to the amount of painkillers going through the epidural, or some adjustment to the catheter in your back, in order to give you adequate pain relief. If this doesn’t work, you may need to have the catheter reinserted.

What if I need an operation after epidural insertion?

If you need an emergency procedure, the epidural catheter can be used to give you a strong local anaesthetic. This will make your abdomen and legs numb enough for you not to experience pain during the procedure.
If the epidural works well, there will be no need for another injection or general anaesthetic.
Occasionally the epidural may not work well enough to be used for a Caesarean section. If this happens, you will need an additional anaesthetic such as a spinal or general anaesthetic to allow the surgery to proceed.

Who cannot have an epidural?

Most people can have an epidural, but having certain medical problems, spine abnormalities such as spina bifida, previous back operations or problems with blood clotting, may mean that an epidural is not suitable for you.

The best time to find out about this is before you are in labour. If you have any doubts, you can request to make an appointment with an anaesthesiologist to discuss your pain relief options.

Epidural does not…

An epidural does not increase your chance of needing a Caesarean section.
An epidural does not increase your chance of long-term backache. Backache is common in pregnancy and often continues afterwards, with or without a labour epidural. You may have a tender spot in your back after an epidural which is self-limiting, but rarely, may last for months.

Benefits	Side effects / complications
It is the most effective labour pain relief.	Common, but minor self-limiting side effects such as reduced blood pressure, weak legs, slight fever, difficult urination, shivering and itchiness can occur while the epidural is working.
There are minimal side effects to your baby.	May prolong second stage (cervix is fully dilated) of labour. There is an increased chance of instrumental (vacuum or forceps) delivery. (17% with epidural, 12% without).
In certain serious medical conditions such as high blood pressure, heart or lung problems or morbid obesity, epidural helps by decreasing the stress of labour on your body.	Inadequate pain relief for labour in 1 in 10 -20 women, which requires troubleshooting and/or reinsertion. Inadequate supply of anaesthesia for emergency procedures in 1 in 8-10 women.
In some obstetric conditions, such as complicated labour or twins, an epidural may help your baby because it enables the obstetrician to delivery your baby quickly if urgent obstetric intervention (e.g. forceps or caesarean section) is needed.	1 - 2% of women could get a severe positional headache that could last for days or weeks if left untreated. If this happens, please inform your anaesthesiologist, who will discuss with you about available treatment options.
	Nerve damage may occur, can be short lived (1 in 3000) or long lasting (1 in 80,000 – 320,000).
	Other rare risks: Epidural haematoma (an epidural blood clot which may press on nerves and may require emergency operation to treat): 1 in 168,000 Epidural abscess or deep infection (which may require emergency operation to treat): 1 in 145,000 Meningitis: 1 in 100,000