Final answer:
The registered nurse determines the patient's pulse rate and fetal heart rate simultaneously with a fetoscope while examining a pregnant patient to assess their cardiovascular status and monitor the baby's heart health.
Step-by-step explanation:
The registered nurse determines the patient's pulse rate and fetal heart rate simultaneously with a fetoscope while examining a pregnant patient because it provides important information about the health and well-being of both the mother and the fetus. By assessing the pulse rate, the nurse can determine the mother's cardiovascular status and identify any abnormalities or concerns. Simultaneously, by listening to the fetal heart rate, the nurse can monitor the baby's heart health and detect any irregularities that may require further investigation or intervention.