Opioid

Opioids are not divided pharmacologically into a helpful analgesic effect and unrelated side effects. Mu-opioid receptor activity produces analgesia, but the same activity can lower arousal and ventilatory drive, constrict the pupils, slow gastrointestinal movement, and cause euphoria. A patient can therefore report excellent pain relief while moving toward life-threatening toxicity. The experienced nurse watches the patient's wakefulness and breathing quality, not the pain score alone. Increasing drowsiness, difficulty staying awake, shallow or irregular respirations, snoring or gurgling, cyanosis, or a new inability to respond changes the priority from comfort management to airway and ventilation support. The respiratory rate must be interpreted with sedation, depth, effort, oxygenation, and the timing of the last dose.