A patient on day 2 of total parenteral nutrition (TPN) has a… | MyMerci
NCLEX-RNPPT
Question
A patient on day 2 of total parenteral nutrition (TPN) has a capillary glucose of 248 mg/dL. The TPN bag has 8 hours remaining. Which is the most appropriate nursing action?
1Stop the TPN immediately and switch to D5W to prevent further hyperglycemia.
2Continue the TPN at the current rate, notify the provider, and anticipate added regular insulin in the next bag (or sliding-scale subcutaneous insulin per protocol) with continued capillary glucose monitoring every 4 to 6 hours.✓ Correct answer
3Increase the TPN infusion rate to deliver the remaining volume more quickly so a new bag can be hung sooner.
4Discontinue the central line until the glucose normalizes.
Explanation
Hyperglycemia on TPN is managed by continuing the TPN at the current rate (abrupt discontinuation causes REBOUND HYPOGLYCEMIA) and adding regular insulin to the next bag or using sliding-scale subcutaneous insulin per protocol, while monitoring capillary glucose every 4-6 hours. Choice 1 is dangerous — abruptly stopping TPN causes hypoglycemia because the patient's endogenous insulin response is calibrated to the dextrose load. Choice 3 worsens hyperglycemia. Choice 4 is unnecessary and removes nutrition delivery.
In-depth explanation
The TPN hypoglycemia rebound is the most-tested mechanism: stopping TPN abruptly causes a 30-60 minute lag of high endogenous insulin meeting NO dextrose, leading to hypoglycemia. If TPN must be stopped, taper down OR hang D10W to bridge.
Clinical scenario
Day 2 of TPN through a central venous catheter. Capillary glucose 248 mg/dL. The TPN bag has 8 hours remaining. Vital signs stable; patient denies polyuria.
Key concepts
TPN-induced hyperglycemia — Common in early TPN due to high dextrose load; managed with continued infusion + added insulin, not discontinuation.
TPN rebound hypoglycemia — Hypoglycemia after abrupt TPN stop because endogenous insulin lags; prevent by tapering or D10W bridge.
Capillary glucose monitoring on TPN — Every 4-6 hours initially; adjust frequency as glycemic stability improves.