A nurse is reinforcing teaching with a client about heart disease prevention. Which of the following client statements indicates an understanding of the teaching?

Monitor for at least 150 mL of drainage every hour. The nurse should monitor the chest tube drainage for excessive or sudden increases in order to detect any complications, such as pneumothorax. Clamping the tube for 30 minutes every 8 hours is not standard practice and can cause complications. Pinning the tubing to the client's bed sheets can cause traction on the chest tube and should be avoided. The chest tube unit should only be replaced when there is a problem with the unit or the seals.

Choice B: Clamping the tube for 30 minutes every 8 hours is not standard practice and can cause complications.

Choice C: Pinning the tubing to the client's bed sheets can cause traction on the chest tube and should be avoided.

Choice D: The chest tube unit should only be replaced when there is a problem with the unit or the seals.

The correct answer is choice B: Store opened insulin vials at room temperature for up to 4 weeks.

Choice B rationale: Opened insulin vials can be stored at room temperature (59°F to 86°F or 15°C to 30°C) for up to 4 weeks. After this period, the insulin may lose potency, and a new vial should be used.

Choice A rationale: Regular insulin is short-acting, and its peak effect occurs 2 to 3 hours after administration. Eating a snack 6 hours after insulin administration may not be necessary as the insulin would have already reached its peak effect, and blood glucose levels should be monitored accordingly.

Choice C rationale: Warming the insulin vial to dissolve crystals is not recommended. Insulin should be inspected before use, and if crystals or clumps are present, it should be discarded as this could indicate that the insulin has lost its effectiveness.

Choice D rationale: Unopened insulin vials should be stored in the refrigerator (36°F to 46°F or 2°C to 8°C) and should not be frozen. Freezing can cause insulin to lose potency or become ineffective. Once opened, insulin vials can be stored at room temperature for up to 4 weeks, as mentioned in choice B.