Final answer:
Before administering hydromorphone for postoperative pain, the nurse should notify the provider if the client has an allergy to aspirin.
Step-by-step explanation:
Before administering hydromorphone to a client, the nurse should notify the provider if the client has an allergy to aspirin. This is because hydromorphone belongs to the class of medications called opioids, which includes drugs like opium, heroin, fentanyl, morphine, oxycodone, and others. Opioids can cross-react with aspirin, leading to an allergic reaction. Therefore, it is essential for the nurse to inform the provider about the client's allergy to aspirin before administering hydromorphone.