The physician orders Humulin NPH insulin 20 units plus Humulin R insulin 11 units subcutaneous every evening. The medication is supplied in 100 units/mL. How many units will the nurse administer?

Choice A rationale: Atherosclerosis is a common complication of diabetes, but it's a macrovascular complication, not a direct result of diabetic neuropathy. Neuropathy affects the nerves, while atherosclerosis involves the hardening and narrowing of arteries due to plaque buildup, which is a separate but related long-term complication of hyperglycemia. Choice B rationale: Diabetic retinopathy is a microvascular complication of diabetes that affects the blood vessels in the retina of the eye. It is not caused by neuropathy. Neuropathy affects peripheral nerves, leading to sensory, motor, or autonomic dysfunction, and is a distinct complication of diabetes. Choice C rationale: Diabetic neuropathy, particularly peripheral sensory neuropathy, causes a loss of protective sensation in the feet. Patients cannot feel pain, pressure, or temperature, making them unaware of injuries, blisters, or cuts. This lack of sensation places them at high risk for undetected foot injuries, which can lead to ulcers, infections, and even amputation. Choice D rationale: Kidney failure is a complication of diabetic nephropathy, which involves damage to the small blood vessels in the kidneys (glomeruli). It is not a direct result of diabetic neuropathy. While both are microvascular complications of diabetes, they affect different organ systems and have different pathophysiological mechanisms.

Choice A rationale: Insulin lispro (Humalog) is a rapid-acting insulin analog. Its amino acid sequence has been modified to allow for rapid absorption from the injection site into the bloodstream. This modification prevents the formation of hexamers, which are slowly absorbed, allowing the insulin to become biologically active within 15 minutes of administration.
Choice B rationale: Regular insulin, a short-acting type, typically has an onset of action of 30 to 60 minutes. Intermediate-acting insulins like NPH have a much longer onset, starting around 1 to 2 hours. Insulin lispro's rapid action is designed to be taken with meals to control postprandial hyperglycemia, which begins immediately after eating.
Choice C rationale: An onset of 80 minutes falls outside the typical time frame for both rapid and short-acting insulins. The pharmacokinetics of insulin lispro are specifically engineered for a quick onset to coincide with mealtime glucose spikes, and its action is not delayed for over an hour.
Choice D rationale: The peak effect of insulin lispro is around 1 to 2 hours, but its onset is much faster. Long-acting insulins like glargine (Lantus) have a much more prolonged effect, with a duration that can extend to 24 hours, but they lack a distinct peak. The 3 to 5 hour period is too long for the onset of a rapid-acting insulin.