There are deficiencies and that undoubtedly will have an impact on whether or not a patient survives in some cases

Mr Keith Porter, Selly Oak Hospital, Birmingham

It is widely accepted that high concentrations of oxygen helps to save the lives of people who are severely injured, and all ambulance services have this capacity.

But a quarter of the services did not carry the appropriate oxygen mask to achieve this.

Only one in five routinely carried nasopharyngeal airways, used to deliver oxygen to patients with facial muscle spasm.

And only 13% carried an alternative to the tube used to ventilate the windpipe, the endotracheal tube.

Traction splints are not uniformly used, with almost a third of services not carrying them and almost four out of 10 services still rely on inflatable splints despite concerns that they restrict blood circulation.

And only a third of ambulance services authorised their staff to decompress tension pneumothorax - where air is trapped in the chest, which can kill if not released - despite having the necessary equipment.

Expanded role

The role of paramedics has expanded, say the authors, so it is not surprising that the range of equipment in front line ambulances has increased.

But the significant variations will affect the treatment, and possibly survival, of patients, they say.

And certain pieces of equipment should not be regarded as optional.

The survey was carried out by Mr Keith Porter, an accident and emergency consultant at Selly Oak Hospital, Birmingham.

He said work had begun on national standards for the equipment that should be carried by every ambulance.

"If we are to set national protocols for the type of treatment paramedics are expected to provide then it is imperative that we provided them with appropriate equipment.

"At present, there are deficiencies and that undoubtedly will have an impact on whether or not a patient survives in some cases."

Significant improvement

Richard Diment, chief executive of the Ambulance Service Association, said the situation had improved significantly since the study was carried out in 1997.

He told BBC News Online: "Talking to our members they feel the position may well be very different today."

Mr Diment said ambulance services were responsible to local paramedic committees staffed by medical experts such as A&E consultants and cardiologists.

"Medicine is not an exact science, and different doctors have different thoughts about what is the best way forward."

Mr Diment said there was also a debate about whether it was desirable for ambulance workers to be trained to undertake procedures required so infrequently that it would be difficult to keep their skills fresh.

The research is published in the journal Pre-Hospital Immediate Care.