Ketamine for pain management

Authors: Bell, Rae Frances et al

Key Points

1. There is good evidence that perioperative ketamine decreases postoperative pain scores and opioid requirements, but there is a lack of consensus on dose, for both bolus and infusion.
2. Despite limited evidence, a trial of low-dose intravenous or subcutaneous ketamine adjuvant to morphine may be warranted in refractory cancer pain.
3. There is only very limited evidence for the use of ketamine in chronic noncancer pain and concerns and a lack of safety data concerning long-term or repeated treatment. Importantly, there is no strong evidence to support the current practice of treating chronic noncancer pain with repeated intravenous infusions.
4. Ketamine has dose-dependent adverse effects, and there are good arguments for avoiding high doses.
5. Spinal administration is associated with neurotoxicity, whereas oral ketamine has low bioavailability and is associated with adverse effects.