Final answer:
The client is likely experiencing decreased blood pressure and requires increased hydration, commonly associated with circulatory shock, which is treated with intravenous fluids and possibly medications.
Step-by-step explanation:
The nurse should identify that the client is most likely experiencing a decrease in blood pressure; the nurse should address the client's need for increased hydration. A patient who arrives in the emergency department with a blood pressure of 70/45, confused and complaining of thirst, is likely experiencing circulatory shock. This condition often presents with symptoms such as an increased heart rate, decreased blood pressure, confusion, thirst, and reduced urine output. The treatment commonly involves providing intravenous fluids to restore normal function and may include medications to raise blood pressure.