A nurse teaches a client who is diagnosed with diabetes mellitus. Which statement should the nurse include in this client's plan of care to delay the onset of microvascular and macrovascular complications?

Choice A rationale: Maintaining tight glycemic control is paramount for delaying both microvascular and macrovascular complications in diabetes. Hyperglycemia causes damage to the endothelial lining of blood vessels through several mechanisms, including increased oxidative stress and advanced glycation end-products (AGEs) formation. This damage leads to capillary basement membrane thickening and impaired vasodilation, which are precursors to retinopathy, nephropathy, and neuropathy (microvascular), as well as atherosclerosis (macrovascular).
Choice B rationale: Restricting fluid intake to 2 liters a day is not a standard recommendation for delaying vascular complications in diabetes. While fluid management is important, especially in the context of advanced nephropathy, a blanket restriction can lead to dehydration and is not directly tied to preventing hyperglycemia-induced vascular damage. The primary focus for preventing complications remains strict glucose and blood pressure control.
Choice C rationale: While preventing hypoglycemia is crucial for a diabetic's safety, eating a bedtime snack is a strategy to avoid nocturnal hypoglycemia, not a direct intervention to delay long-term microvascular and macrovascular complications. The primary driver of these complications is chronic hyperglycemia, not acute episodes of low blood sugar. Long-term glycemic control is the main goal to prevent vascular pathology.
Choice D rationale: Limiting protein intake is a measure sometimes recommended for clients with diabetic nephropathy to slow the progression of kidney disease. It is not a primary strategy to prevent ketoacidosis. Ketoacidosis is primarily caused by severe insulin deficiency, leading to the breakdown of fat into ketones as an energy source, and is not directly related to protein intake.

Choice A rationale: Glucose is a primary fuel source, but the body can also use fatty acids and amino acids for energy through metabolic pathways like beta-oxidation and gluconeogenesis. The brain, however, has a high metabolic rate and is highly dependent on glucose as its main energy substrate because fatty acids cannot cross the blood-brain barrier efficiently.
Choice B rationale: The brain is almost exclusively dependent on glucose for its energy needs, as it lacks the ability to store glucose as glycogen and cannot effectively utilize other energy sources like fatty acids. A sustained blood glucose level below the normal range, typically below 60 mg/dL, impairs cerebral function, leading to symptoms like confusion and lethargy.
Choice C rationale: The production of red blood cells, a process called erythropoiesis, occurs primarily in the bone marrow. This process is regulated by the hormone erythropoietin and depends on nutrients like iron, vitamin B12, and folic acid. It is not directly linked to a minimum blood glucose level in the way that brain function is.
Choice D rationale: Lactic acid is produced during anaerobic metabolism when oxygen supply is insufficient, not due to low blood glucose. While severe hypoglycemia can lead to metabolic disturbances, lactic acidosis is typically associated with conditions like shock or certain metabolic disorders, not directly with low blood glucose levels.