Labour & Delivery - Pain Relief Options Explained: Part Two

The most common method of anaesthesia for caesarean section is a regional block.  If you already have an Epidural in place then that can often be topped up and you can proceed straight into theatre.  If you’re having an elective caesarean then you may have a Spinal or Combined Spinal Epidural.  The benefit of an Epidural for pain relief during labour is that it delivers the best pain relief compared with all other treatment options.  Should you proceed to Caesarean then there is also less acid in your baby’s blood (compared with General Anaesthetic), and your baby is less likely to need help with breathing compared with other methods of administering opioid drugs (i.e. intravenous opioids). 

There are a small amount of risks associated with an Epidural or Spinal.  Back pain is relatively common in pregnancy and can often persist after delivery.  With an epidural/spinal there is no increased chance of back pain – this is often the commonest misconception I encounter.  I like to think of risks as being in groups of ‘more common’, ‘uncommon’ and ‘vanishingly rare’.  The ‘more common’ risks of an epidural or spinal include having transiently low blood pressure (although this is treatable and stops once the epidural/spinal is over), feeling dizzy or nauseated, and perhaps developing shakes or shivers.  In a caesarean, you will also need the help of a catheter to pass urine.  The main (uncommon) risk is developing a headache after insertion - one in every 100 women have an epidural, and one in every 500 having a spinal will develop this.  The vanishingly rare risks include a 0.007% risk of permanent nerve damage, 0.002% risk of developing meningitis, 0.001% risk of developing a haematoma, and 0.0004% risk of developing paralysis.  Interestingly, you are more likely to develop nerve damage from labour itself than an epidural.

The other option of anaesthesia for caesarean section is a general anaesthetic.  This is the method of choice in true emergencies where there is a threat to the life of you or your baby.  This option is still very safe for both you and your baby and current evidence shows that neither General Anaesthetic nor Spinal/Epidural are superior to the other.  The downside of a General Anaesthetic is that your partner or support person cannot be in the room, although your midwife/LMC will be there for your baby’s first moments.
The side effects of the commonly used drugs I talked about in my previous post are all very low risk.  Nitrous Oxide can be associated with disorientation, drowsiness and nausea in up to 0.4% of patients after prolonged use. Pethidine is a common drug of choice in many birthing units, although is going out of favour. When used during labour it crosses the placenta and its effects on the foetus are dependant on dose and timing of administration. In some cases babies have been shown to be sleepier, and less likely to establish breast-feeding in the first few hours although they do have normal APGAR scores. Pethidine is also used to treat the shivering that can develop after anaesthetic.  Because your baby will have been delivered at this time, it is safe to use. Other opioid drugs e.g. Morphine and Fentanyl may also cross the placenta if used during labour, however they are usually used in very small doses. 

Local Anaesthetics are part of both Epidurals and Spinals.  Because they are not administered systemically, and are only administered in very small doses, the risk of any side effects to you or your baby are vanishingly rare.  It is always important to consider the risks and benefits of decisions we make – especially in labour.  Whilst the medications you can choose from do all have side effects, the experience of prolonged pain can also be harmful on the body, and the decision you make is a very personal one.  The medications available in Australia and New Zealand for labour are chosen specifically for their safety when used in the presence of an experienced healthcare professional. 

I hope that the information I have provided you with can help equip you to make the best decisions for you and your baby when the time comes! Looking forward to our next talk about health soon,

xx Morgan