A nurse is assessing a client who has received oxycodone. The nurse notes that the client’s respiratory rate is 8/min. The nurse should identify that which of the following is the pathophysiology for the client’s respiratory rate?

A. Oxycodone promotes vasodilation of cranial arteries. This is not the primary mechanism by which oxycodone affects respiratory rate. Vasodilation of cranial arteries is not directly related to respiratory depression. B. Oxycodone blocks the sodium channel suspending nerve conduction. This is not the primary mechanism of action for oxycodone. Oxycodone primarily acts on opioid receptors rather than sodium channels. C. Oxycodone inhibits prostaglandin synthesis. This is not the primary mechanism of action for oxycodone. Inhibition of prostaglandin synthesis is more characteristic of nonsteroidal anti-inflammatory drugs (NSAIDs). D. Oxycodone causes central nervous system depression. This is the correct explanation. Oxycodone, like other opioids, depresses the central nervous system, which can lead to respiratory depression by reducing the brainstem’s responsiveness to carbon dioxide levels in the blood.