Epidural for pain relief in labour
What can one say about epidural analgesia in labour?
This is a method of pain relief that involves the injection of a local anaesthetic in the lower spine. This acts on the nerve roots that control pain sensation in the lower abdomen, the pelvis and the lower limbs. The effect is freedom from labour pains. A fine flexible catheter is left in place to allow repeated top-ups of the local anaesthetic as and when the effect starts to wear off.
Alternatively, the anaesthetic may be infused continuously rather than intermittently through this fine catheter.
How effective is the epidural in controlling pain?
The epidural is by far the most effective method of pain control available for a labouring woman. In fact, the epidural is not in the same league as the other pain control methods as it the only method which can render the person completely pain-free.. No other method currently available can achieve this.
Does the epidural work every time?
Most times. Unfortunately, for a small minority, the epidural may not work very well and they will continue to feel pain. The most likely failure of an epidural is a scenario where only an isolated area remains unaffected. This is commonly called a "window". Because the rest of the region is completely pain-free, the window area is felt quite acutely. It is often difficult to solve this problem, short of replacing the catheter. It needs to be emphasized that epidural failure is an uncommon event.
Does the epidural have any additional advantages?
Yes. The pain control is so effective that if a caesarean section becomes necessary in the course of labour, the epidural will usually be adequate for the procedure. Only a top-up is usually required. This is, of course, if the labouring mother is not averse to the idea of staying awake for the operation.
Needless to say, a working epidural is more than sufficient for forceps or ventouse delivery.
Is anything special required for the epidural?
To insert the epidural catheter requires expertise and this is done by an anaesthetist. Trained midwives will give top-ups or monitor the infusion.
Are there any unwanted effects from the epidural?
There are occasional unwanted effects, all of which can be solved easily. An immediate unwanted effect could be an ‘ascending epidural’, where the effects extend upwards to affect the chest and the respiratory muscles. This will produce respiratory difficulties, which will require a change in position to a semi-sitting or propped up posture and, occasionally, respiratory support. It soon resolves. Fortunately, this is an exceptionally rare occurrence.
The epidural also tends to lower the blood pressure and that is why an intravenous infusion will always be started before the epidural, to offset this effect.