Expecting a baby is definitely one of the most joyous experiences in your life, so it Is important that the labour and delivery are safe and pleasant. Tolerance to labour pain varies amongst individuals, but it is best for you to be open-minded to all pain relief methods. Your active participation in planning your childbirth together with the help of your obstetrician, the anaesthetist, the midwife and your partner, will help you experience a comfortable and rewarding labour.
What is labour pain all about? Labour pain is usually divided in to three stages:
All these sensations are conveyed through the nerves to your spine, where messages are transmitted to the brain which releases the pain signal to your body.
It is difficult to predict how long your labour will be. It can range from a few hours to twelve hours or more, but it is important to realise that prolonged pain and stressful labour is undesirable for both yourself and your baby. Resorting to pain relief methods during labour is not an indication of failure, but is a means of having a pleasant birth to which every mother-to-be is entitled.
What can I do to relieve my labour pain? Different methods are available to relieve labour pain. Effectiveness varies among individuals, but it is helpful to familiarise yourself with the more common methods before you go into labour, so that you will be able to come to a quick decision when necessary.
Epidural Analgesia (EA) / Combined Spinal-Epidural Analgesia (CSEA) Epidural Analgesia is one of the most effective and reliable ways of relieving labour pain. An injection is done to locate the epidural space within the backbone canal and a fine plastic tube is inserted. Pain relief is accomplished by injecting painkillers through the small tube. Medication can be continued through this small tube via an automated infusion pump, or a patient-controlled pump.
In Combined-Spinal-Epidural Analgesia, in addition to the above EA, an initial dose of pain killers is given into the spinal space for pain relief. CSEA takes effect faster than EA. A fine tube is also inserted to deliver the painkillers continuously throughout labour subsequently.
The anaesthetist will decide if EA or CSEA will be used depending on the stage and progress of labour.
Complete pain relief cannot be guaranteed throughout labour as different women respond differently. Also, effective pain relief must be balanced against the side effects, and some degree of pain may still be felt with EA/CSEA, especially near the time of delivery of the baby.
Benefits of EA/CSEA This method of pain relief has the following benefits:
Side effects and complications of EA/CSEA It is generally safe to receive EA/CSEA. The side effects are usually predictable, short-lived and not harmful. They can be divided into:
Common side effects
Those who smoke, are overweight, diabetic, have high blood pressure, or previous heart disease are at higher risk of these complications.
Remifentanil Patient-Controlled Analgesia (Remifentanil PCA) Patient-controlled analgesia (PCA) is an intravenous drug delivery system that allows you to administer your own pain killers when needed. The PCA device is programmed to administer a fixed dose of remifentanil (a short-acting opioid) upon demand, with appropriate pre-set limits on maximal dose of medications delivered in a fixed time interval. For effective use of PCA, you can activate a dose of painkillers when you feel the onset of a contraction. You will also be provided with oxygen supplementation and continuous monitoring of oxygen saturation thorough a finger-probe for safety.
Current medical literature suggests that Remifentanil PCA is less effective than epidural analgesia in providing labour pain relief. It may be considered in patients who cannot or prefer not to have epidural analgesia e.g. bleeding tendencies, previous spine surgery.
Side effects are generally predictable and short-live, but an anti-dote may need to be given in severe cases.
These include nausea/vomiting, drop in maternal heart rate or blood pressure, respiratory depression and sedation of the mother.
Remifentanil has not been shown to harm the baby in current studies. However, there are theoretical risks of causing respiratory depression and sedation in the newborn. If this occurs, a neonatologist will attend to the baby immediately.
Life-threatening complications are very rare. These include muscle rigidity, breathing difficulty and complete cessation of breathing.
Breathing and Relaxation These refer to the breathing exercises and relaxation techniques which you would have probably practised during your antenatal class. When labour starts and you begin to feel pain, concentrating on your breath and breathing out loud may help you relax.
With the help of your partner, your discomfort may also be relieved by gentle massage on your back. You may find this adequate in early labour, but many mothers may have to seek other methods of pain relief when contraction pains become more severe.
Nitrous Oxide Gas / “Laughing gas” This gas, commonly known as “laughing gas” is mixed with oxygen. To use this method, a mask or mouth piece draws gas from a machine beside the bed. You need to take deep and steady breaths before each contraction as it takes about 20-30 seconds for the gas to be effective. The gas is safe. It does not build up in your or your baby’s body. However, the gas may make you feel light-headed, drowsy or nauseous. Not all mothers find this method of pain relief effective.
Injection of drugs Pain relieving drugs such as pethidine (which is the most commonly used) can be injected into your muscles to reduce your labour pain, but their efficacy varies among individuals. They tend to make some nauseous or drowsy and reduce the mother’s cooperation in pushing. In addition, these drugs cross the placenta to the baby to make him/her drowsy and this depresses the baby’s breathing after he/she is born. If this happens, an “antidote” can be given to your baby to reverse these side effects.
Your anaesthetist will advise you on the appropriate type of pain relief method after discussion with you and your obstetrician. Please feel free to direct any questions or express any of your concerns to your anaesthetist.