What vital sign change should the nurse anticipate evaluating after administering morphine?

After administering morphine, the nurse should anticipate a decreased respiratory rate. Morphine is an opioid analgesic that acts on the central nervous system to relieve pain but also depresses the respiratory system as a side effect. This respiratory depression occurs because morphine can suppress the brain’s respiratory centers, leading to slower breathing.

Monitoring the respiratory rate is crucial after giving morphine because significant respiratory depression can lead to hypoxia and may require intervention, such as administering naloxone or providing supplemental oxygen. Therefore, a decreased respiratory rate is a vital sign change that nurses must keep a close watch on following morphine administration, helping ensure patient safety and the effective management of any potential adverse effects from the medication.