What medication should be administered to a patient with a morphine PCA experiencing low respirations and oxygen saturation?

In cases where a patient is using a morphine patient-controlled analgesia (PCA) and exhibits low respiratory rates and diminished oxygen saturation, the appropriate medication to administer is Narcan. Narcan, or naloxone, is an opioid antagonist that reverses the effects of opioids, including respiratory depression caused by excessive morphine administration.

Administering Narcan will quickly counteract the opioid's effects, restoring normal respiratory function and improving oxygen saturation levels. This intervention is crucial in situations of opioid overdose, where respiratory depression can lead to serious complications, including hypoxia or even respiratory failure. Monitoring the patient closely after administration is essential, as the duration of effect of Narcan may be shorter than that of morphine, potentially leading to a recurrence of the respiratory depression if the morphine remains in the system.

The other medications mentioned, such as Ativan, nitroglycerin, and Protonix, are not suitable for reversing opioid-induced respiratory depression and do not address the critical issue at hand, which is managing the overdose scenario effectively.