Entonox: Gas and air suspended at Cambridgeshire hospitals

A number of hospitals have suspended the use of 'gas and air' due to safety fears at the exposure of nitrous oxide

A hospital trust has suspended its use of gas and air pain relief in its maternity units due to the risk of "prolonged exposure" to staff.

North West Anglia NHS Foundation Trust temporarily stopped using Entonox "to protect midwifery and medical teams".

It told patients it was "not a decision made lightly" and was "based on expert external advice".

The trust runs maternity services at Peterborough City Hospital and Hinchingbrooke Hospital in Huntingdon.

In a statement on the trust website, it said there was no danger to mothers or babies from using Entonox but tests on air quality in its maternity units identified a "potential risk" to staff.

The trust apologised "for the anxiety and uncertainty this announcement will cause".

The use of gas and air has been temporarily stopped at the maternity unit at Hinchingbrooke Hospital

The trust also runs maternity services at Peterborough City Hospital

They said pregnant women can still make alternative pain relief choices and hoped to safely reintroduce Entonox soon.

"None of us want our women to be without the option for gas and air during labour," the trust said.

• MP meets mothers over hospital gas and air concerns

Entonox, which consists of nitrous oxide and oxygen, is a well-established form of pain relief and is self-administered by women during labour.

Acute exposure to nitrous oxide can lead to anaemia, due to the vitamin B12 depletion, and has been linked to fertility issues.

The workplace exposure limit is 100 parts per million (ppm).

A number of other hospitals in England, including Ipswich and the Princess Alexandra in Harlow, withdrew Entonox - but have since restored it.

Basildon Hospital stopped the use of Entonox altogether after reinstating the anaesthetic following a brief suspension last year.

An NHS England spokesperson said: "NHS England has been working with the trusts where gas and air supplies have been affected due to differing and localised issues - this is not a widespread issue and patients should continue to access services as normal."