Final answer:
The sign of hyperglycemia a CPCT should be aware of is increased thirst and urination, as high blood glucose levels cause the kidneys to excrete more urine, leading to dehydration and a greater need for fluids.
Step-by-step explanation:
A Certified Patient Care Technician (CPCT) assisting with the care of a patient who has diabetes mellitus should know that increased thirst and urination are signs of hyperglycemia. When blood glucose levels are high, the kidneys try to filter out excess glucose, which leads to frequent urination. This, in turn, can cause dehydration and result in increased thirst (polydipsia). Hyperglycemia is a condition characterized by an abnormally high level of glucose in the blood. It can lead to several symptoms, including but not limited to polyuria (frequent urination), polydipsia (increased thirst), and polyphagia (increased hunger).