The edition · Anaesthesiology
IV dexamethasone comes out on top for preventing rebound pain after nerve blocks
A network meta-analysis ranks intravenous dexamethasone first for stopping the rebound pain that follows a single-shot block, a Caesarean trial shows a quadratus lumborum block adds to intrathecal morphine, and perioperative duloxetine gives real but modest opioid-sparing after joint replacement.
The edition in brief
Rebound pain — the sharp return of pain as a single-injection nerve block wears off — is common and under-managed. A network meta-analysis of 24 trials, 2,130 patients and eight interventions found intravenous dexamethasone had the highest probability of reducing rebound pain incidence (SUCRA 0.91) and was judged definitely superior to control, making it a sensible first-line prophylactic. Perineural dexamethasone and perineural dexmedetomidine ranked best for delaying onset and prolonging time to first rescue analgesia, while pre-emptive opioids were probably worse than nothing. Certainty ranged from very low to moderate, so this ranks options rather than settling them. For Caesarean analgesia, a two-centre randomised trial in 58 women found a lateral quadratus lumborum block reduced early resting pain compared with intrathecal morphine alone, and adding the block to intrathecal morphine further cut resting and coughing pain at 6 hours and worst pain at 24 hours — at the cost of more, mostly mild, pruritus. It is small and needs confirmation, but supports the block as an add-on where early dynamic pain is hard to control. Perioperative duloxetine, in a meta-analysis of 13 trials, produced statistically significant but sub-threshold analgesia after hip and knee replacement, with opioid-sparing at 48–72 hours and less nausea, but more drowsiness and fragile estimates. Today's regulatory sweep found no new anaesthetic drug action; the practice framework remains the ERAS Society core.
For rebound pain after a single-shot block, reach for IV dexamethasone
Give intravenous dexamethasone to prevent rebound pain after a single-shot nerve block, and add a perineural adjunct (dexamethasone or dexmedetomidine) when the goal is to prolong the block.
A quadratus lumborum block adds to intrathecal morphine after Caesarean
Keep intrathecal morphine as the backbone for Caesarean analgesia and add a quadratus lumborum block when early dynamic pain is hard to control — it improved 6- and 24-hour pain in this small trial.
Perioperative duloxetine helps after joint replacement, modestly
Consider perioperative duloxetine as one component of multimodal analgesia for hip and knee replacement for modest pain relief and 48–72 h opioid-sparing, warning patients about drowsiness.
No new anaesthetic drug action today; the ERAS core is the framework
No new anaesthetic drug regulation today; build departmental protocols on the consistent ERAS anaesthetic core and settle the mixed-strength areas — fluids, carbohydrate loading, premedication — locally.
Prevent rebound pain in the anaesthetic room, not on the ward
Manage rebound pain prophylactically at the time of the block — IV dexamethasone, a perineural adjunct where needed, and oral analgesia started before the block wears off.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this one is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for anaesthesiology, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free