Final answer:
The essential concept to be included in post-discharge education for HPN patients is recognizing signs and symptoms of possible complications to ensure prompt medical intervention.
Step-by-step explanation:
The key concept that should be included in the post-discharge teaching regimen for a home parenteral nutrition (HPN) patient is Signs and symptoms of possible complications. This is critical for monitoring the patient's condition and ensuring timely intervention if problems arise. Educating patients on recognizing signs such as fever, redness or pain at the catheter site, and signs of electrolyte imbalances can be lifesaving. Other teaching points will include proper hand hygiene, catheter care, and the procedure for administering parenteral nutrition, but the recognition of complications is essential for preventing severe adverse outcomes.