Final answer:
Institute seizure precautions is the first priority when a patient demonstrates clonus, a sign of potential neurological issues that could lead to seizures.
Step-by-step explanation:
When a nurse reports that a patient demonstrated clonus on a prior assessment, the immediate priority action for the on-coming nurse is to institute seizure precautions. Clonus is a series of involuntary, rhythmic, muscular contractions and relaxations that are most often a sign of upper motor neuron (UMN) disease. It is considered to be a neurological sign indicative of a potential serious condition such as a seizure disorder. The on-coming nurse should ensure the patient's environment is safe to minimize harm in case of a seizure, which may include padding side rails, ensuring a patent IV line is available for emergency medication administration, and placing the bed in the lowest position. Assessing for pain and repeating vital signs remain essential, but securing the patient's safety through seizure precautions is the priority following a sign of potential neurologic instability.