Common side effects of epidural anaesthetics are nausea, shivering, urinary retention, temporary weakness of one or both legs, and dizziness. Backache, which may occur after pregnancy, has not been shown to be related to the use of epidural anaesthesia during labour.
Occasionally, because of difficulty in locating the epidural space or because of patient movement during insertion, the epidural needle may penetrate the membrane (the dura) containing the spinal fluid allowing spinal fluid to leak. This can produce a headache which, untreated, may last for days or weeks. The risk of this occurring is approximately 1% (one in a hundred). An anaesthetist can arrange to seal the leak caused by this 'dural puncture' by injecting a small amount of your own blood into your epidural space ('a blood patch'). This 'blood patch' is approximately 90% effective in curing the headache.
Other potential (but less common) risks include a fall in blood pressure which may distress the baby, inadvertent intravenous injection of the local anaesthetic causing fitting, or a high 'spread' of the anaesthetic which may cause temporary difficulty with breathing or loss of consciousness.
Rare but potentially serious complications associated with epidural anaesthetics include infection and bleeding in or around the spine, bruising or scarring of the nerve roots leading to permanent weakness and numbness in the legs and bladder problems, cardiac arrythmias, cardiac arrest and death. It is important to realise that the risk of these complications occurring is very small and that the primary goal of the anaesthetist is always the safety of you and your baby.
For more information please refer to www.allaboutanaesthesia.com.au