An external insulin pump is prescribed for a client with diabetes mellitus. The client asks the nurse about the functioning of the pump. The nurse bases the response on the information that the pump:

Choice A rationale: An external insulin pump is a device designed to mimic the normal function of the pancreas. It provides a continuous, basal infusion of rapid-acting or regular insulin subcutaneously to maintain a steady blood glucose level. The client can then manually administer a bolus dose before meals to cover the carbohydrate intake, providing greater flexibility and precise glucose management. Choice B rationale: Insulin pumps use rapid-acting or regular insulin, not NPH insulin. NPH is an intermediate-acting insulin, and its delayed and prolonged action is not suitable for the precise, continuous, and meal-time dosing regimen of an insulin pump. Pumps require fast-acting insulin to manage immediate glucose fluctuations. Choice C rationale: Insulin pumps are external devices and are not surgically attached to the pancreas. They are worn on the body and deliver insulin into the subcutaneous tissue through a small catheter. The pancreas is an internal organ, and this type of surgical intervention is not a feature of standard insulin pump therapy. Choice D rationale: The pump uses rapid-acting or regular insulin, not NPH insulin. While it does provide a continuous infusion, the client still needs to manually monitor their blood glucose levels and adjust their bolus doses accordingly. The pump itself does not continuously monitor blood glucose levels without an integrated continuous glucose monitor (CGM) system, which is a separate but often used device.