By Dr McLeod , consultant anaesthetist and honorary clinical reader at Ninewells Hospital and Medical School, Dundee.

Tens of thousands of pregnant women could be spared unnecessary distress and pain during labour if the latest ultrasound technology were routinely used during epidurals.

One in four epidurals difficult to insert

Research shows that around one in four epidurals given to women to provide pain relief during childbirth is difficult to insert – and there are particular cases which anaesthetists regard as particularly complicated. This not only causes distress, but can mean delays in women receiving pain relief.

It can also lead to other symptoms such as patchy numbness, heavy legs, and headaches for days after delivery for over 63,000 women a year in England and Wales.

Ultrasound could make birth less traumatic

Yet, increasingly, research shows that the use of advanced ultrasound equipment to help medics insert epidurals accurately, could revolutionise the care of women during childbirth, making the birth less traumatic.

For some time I have wanted to change regional anaesthesia to the ultrasound procedure with direct visualisation, which guides the needle to the precise position required.

I am particularly impressed with the work carried out at the Mount Sinai Hospital in Toronto, Canada, where the use of advanced ultrasound technology within the delivery suite increased the successful insertion rate for epidurals (when using ultrasound equipment) to 91.8 per cent.

Epidurals increasingly difficult to administer

While epidural anaesthesia is a form of pain relief which has been used on maternity wards for almost 40 years, it is increasingly difficult to administer.

In addition, there are certain cases which are well documented as particularly problematic –long labours, and women who are overweight.

These more complicated labours really test the ability of the anaesthetist to correctly administer epidurals.

• Long labours – patients with long, difficult labour tend to have more pain and are more likely to request an epidural.

• Request in late labour – patients in late labour have more pain and often little time between contractions. It is important that epidural needles are inserted between contractions when the woman is still otherwise the needle may accidently enter blood vessels.

• Obese women – there are increasing cases of women coming into the delivery suite, with a BMI over 40 which causes a great challenge because bony landmarks and the midline are difficult to feel.

The way the epidural drug is inserted into the spine is crucial because it determines the success or failure of the pain relief, and rate of absorption of the drugs.

This is a delicate and tricky procedure, as the space in the spinal column varies from woman to woman.

As well as discomfort and distress during delivery, inaccurate application of epidural anaesthesia can lead to headaches, numbness down one leg, a patchy block on the abdomen, rectal pressure, heavy legs due to high doses of the drug because pain is difficult to control and several rescue injections.

Technological advances can help consultants

It disturbs me that despite technological advances, consultants across the UK are still carrying out the procedure ‘blind’, guessing the right place to insert the drugs simply by feeling the spine – yet there is no need. There is now a solution to help.

Having being inspired by the work in Canada, I have led a number of studies at Ninewells Hospital, Dundee, to explore the use of ultrasound in these circumstances and we have found that a new small curvilinear probe is all that is necessary to visualise the important anatomical structures in the majority of women.

Z.ONE Ultra system from Zonare offers latest imaging device

We have selected the Z.ONE Ultra system from Zonare which offers the latest imaging device. As well as premium images, it is a new form of technology which can be updated regularly with upgradeable software – we are effectively getting a new machine each time it is updated.

The ultrasound images identify the mid-line, the correct space between spines, and measures the distance from the skin to the epidural space.

Zonare is central to our transational work, as our research projects are enabling us to bring ideas from science into the clinic – and in the case of maternity, making a real difference to so many women.

Epidurals increase in popularity

As epidurals continue in popularity – with up to 60% of first time mums opting for epidural pain relief in some hospitals – I think it is time to make use of the technology which has the potential to reduce severe spinal headaches from the current incidence of 1 in every 200 epidurals, by recognising anatomical variation and avoiding inserting the needle too deep.

Imaging which identifies the midline and interspace between the bones in the back, where the epidural is inserted, offers a huge advantage. We then face fewer complications and increased maternal satisfaction.

About Dr McLeod

As Clinical Lead for Research in Anaesthesia (at Ninewells Hospital), he has led 10 studies into anaesthesia, from use of ultrasound to visualise deep lying nerves, to training models, to use of anaesthetic in labour and in knee replacements. Current research includes the use of ultrasound technologies to support needle guidance and their use in clinical practice, following a grant from the Medical Research Council (Developmental Pathway Funding Scheme). Dr McLeod has also received grants from the Anaesthetic Research Society, Obstetric Anaesthetists Association and Chief Scientists Office.

Central to all this research is the Zonare ultrasound equipment, allowing medical teams to have clearer vision and make accurate judgements during procedures, and helping medics bring science into the clinic. Over the past two and a half years, all Dr McLeod’s research and training has used the Zonare machine (purchased through the NHS tendering process), selected against competitors for its clinical strength and ability to upgrade the software to the latest technology.