A nurse is administering hydromorphone to a client who is experiencing postoperative pain. Which of the following findings is an adverse effect of this medication?

Rationale: A. Dilated pupils: Hydromorphone, an opioid, typically causes pupil constriction (miosis), not dilation. Dilated pupils may occur in opioid overdose only as a sign of severe hypoxia, but are not a common adverse effect of appropriate therapeutic dosing. B. Urinary retention: Urinary retention is a known adverse effect of opioids like hydromorphone. Opioids can impair bladder muscle tone and suppress the urge to void by affecting central and peripheral nervous system pathways. C. Hypertension: Hydromorphone generally causes hypotension due to vasodilation and histamine release. Hypertension is not a typical response and would more likely suggest untreated pain or another underlying condition. D. Tachypnea: Opioids depress the respiratory center in the brain, which can lead to bradypnea rather than tachypnea. An increase in respiratory rate is not characteristic of opioid use unless it’s a response to severe, unmanaged pain.