Patients are being put in danger by hospitals allowing junior nurses to take on jobs they are not trained to do, including looking after intensive care patients and administering drugs, a study claims.

A survey of more than 2,500 NHS staff found examples where healthcare assistants (HCAs) are working beyond their competence, including cases where lesser-trained HCAs administered drugs without proper training while others were left in sole charge of patients with complex needs.

Examples from the 2,554 people who responded to a Nursing Standard survey - made up mostly of qualified nurses and nursing students - said HCAs were also managing colleagues and running units and clinics.

Some nurses said HCAs had received training, but others said this was lacking - or HCAs were not competent in interpreting information about patients.

One respondent said HCAs were involved in "caring for 'low-risk' ventilated tracheostomy patients in an intensive care environment".

"The registered nurse working next to them is expected to supervise and overlook everything they do but this is an impossible task when they themselves are looking after a level-3 ventilated patient. As far as I'm concerned this is dangerous."

In another example, HCAs looked after incubated and ventilated patients in intensive care.

This means "on break times a trained member of staff could be left with only a support worker with them and no other registered member of staff, this can create issues with regards to giving intravenous (IV) medications."

Several respondents said HCAs monitored patient vital signs but "did not understand" the results; took blood pressure readings "but do not know what is normal or not"; and failed to notice when a patient was deteriorating.

There were also cases where assistants acted as members of emergency or resuscitation teams and "give medication without knowing what the drugs are for and side effects".

One nurse said: "As a newly qualified nurse who has only been given eight supernumerary shifts I have been asked to give medications when I have not been reviewed."

Another nurse said HCAs were carrying out the "assessment, planning and execution of nursing care that in critical care really should be done by registered nurses".

Standards set by the Nursing and Midwifery Council (NMC) say nurses can delegate aspects of patient care to HCAs, including administering medicines.

However, the nurse is "accountable to ensure that the ... care assistant is competent to carry out the task."

But one nurse in the survey said: "There is sometimes an attitude from unregistered staff that it doesn't matter what they do because ultimately it is the registered nurse looking after the patient who will take responsibility.

"No matter how hard we try to uphold standards it is impossible to be aware of everything going on with our patients, and we have to rely on support staff to provide a high standard of care without having to directly supervise them at all times."

In October, the government unveiled plans for a code of conduct and training for HCAs but ministers are not in favour of statutory regulation which has met with disapproval from nursing bodies.

The plan is designed to "bring clarity" to the training HCAs need to deliver more advanced tasks, although this training will be voluntary.

Dr Peter Carter, head of the RCN, has said the NHS is too reliant on untrained HCAs who are asked to pick up nursing skills as they go along.

He said assistants were employed to help nurses with basic tasks like washing and feeding, but ended up doing much more.

Dr Carter said of the survey: "Today's findings add further weight to the case for mandatory regulation and guaranteed training standards for HCAs, which the RCN has been calling for for some years and throughout the Health and Social Care Bill process.

"The RCN is clear - a voluntary or optional scheme does not go far enough; not only would it continue to put patients at risk, it would also do a great disservice to the hardworking, dedicated HCAs who would welcome regulation."

His call was backed up by RCN head of policy, Howard Catton, who said: "These findings make it clear that if we want to maximise patient safety, we need to push forward with mandatory regulation of support workers.

"There is also a clear need for education and training of support staff to ensure we do not separate tasks from the knowledge required for clinical assessment and decision making."

Meanwhile, Unison head of nursing Gail Adams told the Press Association: "This list reaffirms our findings that HCAs are delivering most bedside nursing as well as many extended roles.

"I question whether some of these roles are appropriate given the lack of consistency and training."

Health minister Lord Howe agreed that HCAs should not be carrying out tasks for which "they are not qualified" and that a new code of conduct would help drive up standards.

"That is why we have commissioned Skills for Health and Skills for Care to develop a code of conduct and minimum training standards for healthcare support workers and adult social care workers in England by Sept 2012.

"We expect these would be used by an assured voluntary register, as part of its standards for inclusion on the register."