Opioid intoxication: The client shows hallmark signs of opioid overdose bradypnea, pinpoint pupils, hypothermia, confusion, and hypotension after a long history of oxycodone use and functional decline. Obtain prescription for naloxone: Naloxone is an opioid antagonist that rapidly reverses life-threatening respiratory depression caused by opioid toxicity and should be administered promptly. Prepare to initiate mechanical ventilation: Due to the client's shallow respirations and oxygen saturation of 90% on room air, assisted ventilation may be needed to maintain adequate oxygenation post-naloxone or if unresponsive. Respiratory rate: Hypoventilation is the most critical complication of opioid overdose; frequent monitoring is essential to detect deterioration or improvement following naloxone administration. Pupillary reaction: Constricted pupils are a key indicator of opioid toxicity. Monitoring for dilation after naloxone helps assess the reversal of opioid effects and neurologic improvement.