Crewing ambulances entirely with staff who are only trained in basic first aid skills is like playing Russian roulette, a paramedic has claimed.

A paramedic working in Wiltshire has revealed how on Sunday night ambulances were double crewed, or staffed by two emergency care assistants (ECAs), instead of one ambulance technician or paramedic and one ECA.

ECAs can give oxygen and use an automatic defibrillator but cannot administer drugs, unlike a technician or paramedic.

The paramedic, who has asked to remain anonymous, said: “Crewing an ambulance with just ECAs is like Russian roulette for patients and double crewing them is happening on a more regular basis.

“The ECA’s job is to assist a technician or paramedic and drive the ambulance.

“Patients who appear stable can suddenly deteriorate and if you have a crew of ECAs patients’ lives will potentially be put at risk. The management will say that ECA crews will be backed up immediately by a higher skilled crew, but that crew could be an hour away. I suspect employing ECAs is a cost-cutting exercise.”

Emergency care assistants earn between £15- £18,000 and take a six to nine week training course. Ambulance technicians earn between £17-£21,000 and complete a 12-week training course.

Great Western Ambulance Service has 236 ECAs, 204 ambulance technicians and 351 paramedics.

Nationally Unison has called for emergency care assistants not to be deployed on front line ambulances unless they are trained to technician level. Ian Whittern, chairman of the Great Western Unison branch, said: “ECAs are not fit for purpose, although that is not a criticism of the individual.

“We are in dispute with the management at GWAS over the use of ECAs on front line ambulances and we are not happy they are being used to double crew ambulances. The public expect the NHS to have an ambulance crew that is trained to primarily treat patients.”

West Wiltshire MP Dr Andrew Murrison said: “It appears that Unison, quite rightly, are wanting to raise the standards of training for emergency crews.

“I think it’s particularly important in an area like ours, which is quite spread out, and where there have been concerns in the past about response times, that our ambulance crews are particularly well trained.”

A spokesman for Great Western Ambulance Service said that five double ambulance crews of ECAs worked in Wiltshire last weekend, four on Saturday and one on Sunday night.

The spokesman said: “We try not to put double ECA crews on ambulances but there are times when we have to.

“We are planning to recruit more paramedics and our aim is to have a paramedic on every ambulance.

“Patient safety is our top priority and using ECAs is not compromising patient safety.”