A client with type 2 diabetes mellitus (DM) is admitted to the hospital for uncontrolled DM. Insulin therapy is initiated with an initial dose of insulin isophane (NPH) subcutaneous at 0800. At 1600, the client reports having diaphoresis, rapid heartbeat, and feeling shaky. Which should the nurse do first?

Rationale: A. Give the client one half cup (120 mL) of fruit juice: Providing a quick source of glucose is appropriate if hypoglycemia is confirmed, but administering treatment before assessing the blood glucose level may lead to inappropriate management if symptoms are caused by another condition. B. Determine the client's current glucose level: The client’s diaphoresis, palpitations, and shakiness are classic signs of hypoglycemia, which is a potential complication of NPH insulin. Confirming the blood glucose level first allows the nurse to verify hypoglycemia and provide appropriate, evidence-based treatment immediately. C. Give the client skim milk and crackers: This is a suitable option for mild hypoglycemia once confirmed, as it provides both rapid-acting glucose and sustained carbohydrate. However, it should only be given after the glucose level is assessed to ensure appropriate intervention. D. Assess the client's oxygen saturation level: While monitoring oxygen saturation is part of general assessment, it does not directly address the acute symptoms indicative of hypoglycemia. Immediate glucose assessment takes priority in this situation.