Final answer:
A nurse should first confirm the low pressure alarm on an arterial line and then troubleshoot to identify the cause, ensuring the blood pressure cuff is properly attached and checking the patient's arterial blood pressure using a mercury manometer if the patient is stable.
Step-by-step explanation:
When the low pressure alarm sounds for a patient with an arterial line, the nurse must first ensure the accuracy of the alarm. This is crucial as it could indicate a real problem such as disconnection or leakage in the arterial line, which can compromise blood pressure monitoring. Immediate troubleshooting should be initiated to identify the cause.
Once the alarm is confirmed to be accurate, the nurse should check the blood pressure cuff and ensure that it is properly attached to the measuring device and assess the patient clinically to rule out any issues that might have led to actual hypotension. If technical issues are ruled out and the patient is stable, the nurse may need to recalibrate or check the operation of the mercury manometer used to measure the patient's arterial blood pressure. Throughout this process, maintaining the sterility of the system and patient safety is paramount.