Opioids: initial use for severe acute pain

Opioids: initial use for severe acute pain

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Morphine and fentanyl are commonly used for the relief of severe acute pain. While effective relief of pain is necessary, opioid overdose carries serious risks. Rapid dose titration seeks an acceptable compromise between prompt analgesia and safety. A small dose is given and doses repeated at intervals of about five minutes until analgesia is achieved or sedation and/or respiratory depression contraindicate further opioid administration. An example of such a process of titration to effect is detailed in Figure 1.4.

The patient should be monitored during intravenous administration of opioids, including sedation score, respiratory rate, and arterial oxygen saturation if possible.

Initial intravenous opioid 'titration to effect' for acute pain in adults (Figure 1.4) [NB1]

NB1: Not appropriate for maintenance of analgesia in continuing pain. Also, note that this figure provides a guideline for the initial management of moderate to severe acute pain in adults using intermittent intravenous opioid administration, and assumes that the patient is not currently on an opioid (ie does not have opioid tolerance).

NB2: The peak effect of an intravenous dose of morphine may not occur for over 15 minutes.

NB3: If within an hour, a patient less than 70 years of age requires more than 20 mg morphine (or 400 micrograms fentanyl), or a patient over 70 years of age requires more than 10 mg morphine (or 200 micrograms fentanyl), the patient’s clinical condition should be reviewed.

NB4: Sedation score: 0 = awake, alert; 1 = mild sedation, easy to rouse; 1S = asleep, easy to rouse; 2 = moderate sedation, unable to remain awake; 3 = difficult to rouse. For further information see Table 1.23.