A nurse is assessing a client who is receiving morphine for pain and has a respiratory rate of 8/min and a blood pressure of 80/40 mm Hg. Which of the following medications should the nurse administer?

Nursing management of a client receiving opioid analgesia requires close monitoring for signs of central nervous system and respiratory depression. Morphine is a potent opioid that can cause life-threatening respiratory depression, hypotension, and decreased level of consciousness, especially in overdose or heightened sensitivity. A respiratory rate of 8 breaths/min with hypotension indicates severe opioid toxicity requiring immediate reversal. Rapid administration of an opioid antagonist is the priority to restore ventilation and prevent respiratory arrest. Rationale: A. Flumazenil is a benzodiazepine antagonist used to reverse effects of benzodiazepines such as sedation and respiratory depression caused by those agents. Flumazenil is not effective against opioid toxicity and would not improve respiratory depression caused by morphine. Therefore, it is not appropriate in this situation. B. Acetylcysteine is an antidote used to treat acetaminophen overdose by replenishing glutathione stores and preventing hepatic injury. Acetylcysteine does not have any effect on opioid-induced respiratory depression or hypotension. It is unrelated to the clinical presentation in this scenario. C. Protamine sulfate is used to reverse the anticoagulant effects of heparin in cases of excessive bleeding or overdose. Protamine sulfate does not address opioid toxicity and would not improve respiratory or cardiovascular depression caused by morphine. It is indicated only for anticoagulation reversal. D. Naloxone is the appropriate medication because it is an opioid antagonist that rapidly reverses the effects of opioids such as morphine. Naloxone competitively binds to opioid receptors, reversing respiratory depression, hypotension, and CNS depression. It is the emergency treatment of choice for suspected opioid overdose and should be administered immediately in this clinical situation.