Final answer:
In oliguria, the patient cannot excrete large amounts of urine, leading to a drop in serum sodium levels when fluids are continuously administered.
Step-by-step explanation:
The statement is True.
In oliguria, the patient is unable to excrete large amounts of urine, leading to a decrease in urine output. As a result, when fluids continue to be administered, the excessive water intake dilutes the serum levels of sodium, causing a drop in its concentration.
For example, suppose a patient with oliguria is given fluid intravenously. As the fluids are administered, the patient cannot excrete a sufficient amount of urine, leading to a buildup of water in the body without an appropriate increase in sodium levels. This dilutes the sodium concentration in the bloodstream, resulting in hyponatremia.