Anna Kaczmarek admitted she wasn't experienced in even basic life support, despite working in Lanarkshire hospitals and care homes for seven years.
A hearing by the Nursing and Midwifery Council found senior nursing managers at the health board had "serious concerns" about her lack of medical knowledge and one recommended her dismissal.
When a patient in Monkland's Hospital suffered a cardiac arrest in the night, the nurse, originally from Poland, froze and screamed for help.
The senior staff nurse and a colleague raced to the scene and found her standing a few feet away from the patient, who was lying on the floor.
They were forced to intervene, clear the patient's airways and start cardiopulmonary resuscitation (CPR). The patient recovered.
The incident happened on February 5-6 in 2012. The nurse was suspended by the NMC but then continued to work shifts, illegally, at Rosepark Care Home in Uddingston.
The associate director for NHS Lanarkshire's Bank Staff said: "This is basic life support and it is taught to all nurses."
The hearing concluded: "A patient's life was put at risk by you not taking appropriate and immediate action.
"The patient required their airway cleared and you did not immediately do that.
"The panel found it hard to believe that you had worked as a nurse for over 25 years and had never apparently come across a situation where a patient had collapsed.
"The panel determined that it was very serious that you worked as a registered nurse for six shifts at the Home while suspended."
Ms Kaczmarek has been banned from working as a nurse for a year with a requirement for more training. The NMC said striking off would be "disproportionate" because it was a single incident.
However NHS Lanarkshire confirmed the nurse would not be re-employed by the board.
The nurse qualified in Poland in 1986 and came to the UK in 2005. She has been doing bank shifts for NHS Lanarkshire and Rosepark Care Home since 2007.
An NHS Lanarkshire spokesman said: "As part of our internal process we referred this individual to the Nursing and Midwifery Council."