Final answer:
Monitoring for hypoglycemia after a 30-unit NPH insulin injection at 7 a.m. should begin around 11 a.m., focusing on the peak activity period of NPH insulin, which is from 4 to 12 hours after injection.
Step-by-step explanation:
When administering NPH insulin, which is an intermediate-acting insulin, you should monitor for signs of hypoglycemia starting from the onset of the insulin's action to when it peaks. NPH typically begins to work within 1-2 hours after injection, with its peak effect occurring around 4-12 hours later, hence the highest risk for hypoglycemia would be during this peak window. Based on this, you should start checking for hypoglycemia in the patient approximately 4 hours after administration, with heightened observation until around 12 hours post-injection.
Given that the insulin was administered at 7 a.m., monitoring should start around 11 a.m. and continue possibly until 7 p.m. It is essential to note individual responses to insulin may vary, and additional factors such as renal function and meal intake may influence blood glucose levels and the timing and risk of hypoglycemia. Therefore, close monitoring and tailored care based on each patient's unique situation are crucial.