Page 27 Acute Pain Management

4. Evidence for a clinically relevant peripheral opioid effect at non‐articular sites, including
perineural, is inconclusive (U) (Level I).
5. Epidural pethidine produces better pain relief and less sedation than IV pethidine after
Caesarean section (U) (Level II).

6. Extended release epidural morphine provides analgesia for up to 48 hours, however
central depressant effects, including respiratory depression, may also be increased and
prolonged (N) (Level II).

 No neurotoxicity has been shown at normal clinical intrathecal doses of morphine,
fentanyl and sufentanil (U).
 Neuraxial administration of bolus doses of hydrophilic opioids carries an increased risk of
delayed sedation and respiratory depression compared with lipophilic opioids (U). SUMMARY

Adjuvant Drugs
1. Intrathecal clonidine improves duration of analgesia and anaesthesia when used as an
adjunct to intrathecal local anaesthetics (N) (Level I).
2. Clonidine improves duration of analgesia and anaesthesia when used as an adjunct to
local anaesthetics for peribulbar, peripheral nerve and plexus blocks (N) (Level I).
3. Intrathecal neostigmine marginally improves perioperative and peripartum analgesia in
combination with other spinal medications but is associated with significant side effects
(S) (Level I).
4. Epidural neostigmine combined with an opioid reduces the dose of epidural opioid that is
required for analgesia (U) (Level I).

5. Epidural ketamine (without preservative) added to opioid‐based epidural analgesia
regimens improves pain relief without reducing side effects (U) (Level I).
6. Intrathecal midazolam combined with a local anaesthetic prolongs the time to first
analgesia and reduces postoperative nausea and vomiting (N) (Level I).
7. Following Caesarean section, intrathecal morphine provides improved analgesia
compared with placebo (N) (Level I) and more prolonged analgesia compared with more
lipophilic opioids (N) (Level II).
8. Intrathecal clonidine added to intrathecal morphine improves and prolongs analgesia (N)
(Level II).

9. Epidural clonidine reduces postoperative systemic opioid requirements (N) (Level II).
10. Epidural adrenaline (epinephrine) in combination with a local anaesthetic improves the
quality of postoperative thoracic epidural analgesia (U) (Level II).
11. In obstetrics, epidural neostigmine improves postoperative analgesia without increasing
the incidence of adverse events (N) (Level II).
12. Addition of either clonidine or dexmedetomidine to intrathecal bupivacaine increases the
speed of onset and duration of motor and sensory block without additional side effects
(N) (Level II).

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