Pain relief and having a baby

Labour is among the most painful human experiences.

Several factors contribute to the pain, including stretching of the cervix in the first stage of labour and stretching of the vagina and perineum in the second stage of labour.

Pregnant women should discuss the methods of pain relief available with the midwife, obstetrician and anaesthetist well in advance of their labour.

Anaesthetists play an important role in providing pain relief so the baby can be delivered safely. Epidurals are the most common and effective form of pain relief for labour and are administered by specialist anaesthetists. Anaesthetists are also involved when pregnant women have their babies delivered by caesarean section, providing the most appropriate form of anaesthesia. This may be either regional anaesthesia in the form of a spinal block, an epidural block, a combined spinal-epidural block, or general anaesthesia.

Some forms of pain relief, such as the injection of medication into a muscle, may be prescribed by a doctor and do not require the services of an anaesthetist.

Pain relief during labour

Nitrous oxide

Women in labour can self administer a mixture of nitrous oxide (N20) and oxygen to help relieve their labour pain, though few find it adequate as the only means of pain relief. It is most effective if started at the very beginning of the contraction before the contraction becomes painful. Often known as “laughing gas”, nitrous oxide is an analgesic and is relatively safe during labour when mixed with oxygen. Many women choose nitrous oxide because it allows them to control their pain relief. The gas is delivered through a facemask or a tube held in the mouth; women can remove the mask or breathe deeply on the gas when they feel a need.

Epidural anaesthesia for pain relief

Epidural and spinal analgesia/anaesthesia provides the most effective relief for labour pain. This is where local anaesthetic – with or without opioid – is administered around the outer coverings of the spinal cord or into the fluid bathing the spinal cord.

Epidural and spinal anaesthesia is administered to patients who are sitting down or lying on their side depending on the anaesthetist’s preference. After washing the back with antiseptic solution, the anaesthetist injects local anaesthetic under the skin to reduce discomfort from the procedure.

Patients are then positioned with a curved back posture, typically described as making the shape of the Sydney Harbour Bridge or an angry cat. By placing the chin on the chest and dropping the shoulders, the space between the vertebrae opens up to facilitate passage of the epidural needle. A fine plastic tube known as an “epidural catheter” may be threaded through the needle, which is then removed.

Local anaesthetic is administered through this catheter to stop women in labour feeling pain from the contractions of the womb and dilatation of the cervix. Medications may be administered by continual flow throughout the labour or by a midwife injecting a prescribed dose into the epidural catheter.

As a general rule, you can request the epidural at any stage during labour provided there are no medical reasons not to, and following consultation with the midwife and/or obstetrician.

An epidural procedure takes between five and 30 minutes to perform, with the onset of pain relief starting within five minutes of the patient receiving the local anaesthetic.

Spinal block

Spinal blocks are commonly performed to achieve anaesthesia for a planned caesarean section. To administer a spinal block (also known as a central neuraxial block), an anaesthetist inserts a fine needle through the skin of the back and injects local anaesthetic into the cerebrospinal fluid, sometimes in combination with other medications. The medication spreads within the spinal fluid to prevent the patient feeling pain.

This form of anaesthesia (neuraxial block) generally works faster than an epidural block and the legs become weaker and heavier more quickly. The dose of local anaesthetic used for spinal blocks is much smaller than that used for epidural blocks. These effects may last for several hours.

Occasionally, an anaesthetist may use a spinal block to provide pain relief for labour during a vaginal delivery. Some anaesthetists perform both a spinal and an epidural block for either labour pain or a caesarean section. This is called a combined spinal epidural (CSE) and is slightly faster in relieving pain from the time of injection

General anaesthesia

General anaesthesia is uncommonly performed on patients requiring caesarean section. When it is used, the reasons might include: an emergency caesarean section where there is no time to perform a spinal or an epidural block; maternal preference; and failed spinal or epidural block (about one in 100). General anaesthesia involves putting a patient into a medication-induced state of carefully controlled unconsciousness. When the anaesthetic is deep enough, the patient will not respond to pain.

Pain relief after delivery

Pain relief after caesarean section

There are many options available to assist with postoperative pain relief after a caesarean section. Typically patients are prescribed simple analgesics, such as paracetamol, and non-steroidal anti-inflammatory drugs, such as diclofenac (Voltaren), to be taken regularly for a few days. Pain relief options depend on the form of anaesthesia and analgesia used for the caesarean section.

Spinal block

An anaesthetist may choose to add an opioid, such as pethidine or fentanyl, to the local anaesthetic drugs injected during a spinal block. This may provide pain relief lasting into the next day. Patients who do not receive spinal opioids may be prescribed oral medicines such as oxycodone or may be prescribed medications to be delivered by patient-controlled anaesthesia (PCA) pump. Patient-controlled analgesia enables a patient to control their own pain relief in a regimen set by their doctor. By pressing a button on a syringe pump, a patient can administer a pre-set dose of pain-relief medication as required. Built-in safety features mean the pump will not deliver more medication than the anaesthetist or pain physician has prescribed.

General anaesthesia

A patient who has had a general anaesthesia for a caesarean section may be given oral opioid medications, such as oxycodone, for pain relief, or the use of patient-controlled analgesia (PCA). Patientcontrolled analgesia enables patients to control their own pain relief in a regimen set by their doctor. By pressing a button on a syringe pump, patients can administer a pre-set dose of pain-relief medication as required. Built-in safety features mean the pump will not deliver more medication than the anaesthetist or pain physician has prescribed.

This information is a guide and should not replace information supplied by your anaesthetist. If you have any questions about your anaesthesia, please speak with your treating specialist.

Last updated 09:08 30.06.2020