A nurse is preparing to administer pain medication to a postoperative client who had a total knee replacement and reports pain as 5 on a scale of 0 to 10. Which of the following PRN medications should the nurse plan to administer?

B) Nalbuphine: Nalbuphine is an opioid analgesic that acts on the central nervous system to relieve pain. When administered concurrently with morphine, there is a risk of additive respiratory depression and other opioid-related side effects, such as sedation and hypotension. Therefore, the nurse should clarify the prescription for nalbuphine with the provider to ensure that the combination of opioid medications is appropriate for the client's pain management. Additionally, nalbuphine has mixed agonist-antagonist properties and can precipitate withdrawal symptoms in clients who are physically dependent on full opioid agonists like morphine. Due to these potential interactions and safety concerns, it is essential for the nurse to obtain clarification from the provider before administering nalbuphine to the client receiving morphine via a PCA pump.

A) Ondansetron: Ondansetron is an antiemetic medication commonly prescribed to manage nausea and vomiting, which can be side effects of opioid analgesics like morphine. There are no significant contraindications or interactions between ondansetron and morphine, making it a suitable choice for adjunctive therapy in clients receiving PCA morphine for cancer pain.

C) Insulin glargine: Insulin glargine is a long-acting insulin analog used to control blood glucose levels in clients with diabetes mellitus. While clients with cancer may have comorbidities such as diabetes, the prescription for insulin glargine is unlikely to require clarification in the context of concurrent morphine use. However, the nurse should verify the client's current blood glucose levels and adjust the insulin dosage as needed based on the client's glycemic control.

D) Acetaminophen: Acetaminophen is a non-opioid analgesic commonly used to manage mild to moderate pain. When used in combination with opioids like morphine, acetaminophen can provide additive pain relief and may reduce the total opioid dosage required. There are no significant contraindications or interactions between acetaminophen and morphine, making it a suitable choice for adjunctive pain management in clients receiving PCA morphine for cancer pain.

A) Naloxone: This is the correct medication to anticipate administering for opioid toxicity. Naloxone is an opioid antagonist that competitively blocks opioid receptors, reversing the effects of opioid overdose, including respiratory depression, sedation, and hypotension. Administering naloxone can quickly reverse the toxic effects of opioids and restore adequate ventilation and consciousness in the client.

B) Atropine: Atropine is not indicated for opioid toxicity. It is an anticholinergic medication used to treat bradycardia and to decrease respiratory secretions, but it does not reverse the effects of opioids.

C) Midazolam: Midazolam is a benzodiazepine medication used for sedation, anxiety reduction, and induction of anesthesia. While it may be used as an adjunct in the management of acute agitation or seizures, it is not the primary medication for reversing opioid toxicity.

D) Dexamethasone: Dexamethasone is a corticosteroid medication with anti-inflammatory and immunosuppressive effects. It is not indicated for the treatment of opioid toxicity.