Final answer:
Among the given scenarios, a hemoglobin level of 7g/dL is the most concerning and requires immediate notification of the doctor due to the risk of severe bleeding or anemia.
Step-by-step explanation:
The student's question is regarding which findings during a post-operative assessment of a client with a total knee replacement should warrant the notification of the doctor. Among the provided options, a hemoglobin of 7g/dL is particularly concerning and would require immediate notification of the doctor. This is because normal hemoglobin levels for adults are generally above 13 g/dL for men and 12 g/dL for women. A value of 7 g/dL indicates a significant drop in hemoglobin and could be a sign of severe postoperative bleeding or anemia, both of which would need prompt medical attention. The other options, such as scant bleeding on the dressing, a low-grade temperature, and a urine output of 120 mL during the last hour, might be expected or non-critical findings two hours post-surgery and do not typically necessitate urgent communication with a doctor.