Final answer:
The nurse should expect to find increased hematocrit levels in a client with diabetes insipidus due to the excessive water loss that leads to dehydration. The condition is also characterized by low urine specific gravity.
Step-by-step explanation:
A nurse assessing a client who has diabetes insipidus should expect to find an Increased hematocrit. Diabetes insipidus is characterized by the kidneys' inability to conserve water as they perform their normal functions of filtering blood. The excessive water loss through urine leads to dehydration, which can elevate hematocrit levels. The client's urine would be very dilute, leading to a low urine specific gravity. Diabetes insipidus should not directly cause a decreased heart rate or a low BUN level. These assessments are vital in the proper management and treatment of a client with diabetes insipidus.