Eur J Pain. 2014 Aug 4. doi: 10.1002/ejp.567. [Epub ahead of print]
Humble SR, Dalton AJ, Li L
In this systematic review of perioperative interventions reducing acute and chronic pain associated with amputation, mastectomy or thoracotomy, 32 randomised controlled trials were included. Gabapentin/pregabalin reduced the incidence of acute and chronic pain after mastectomy, but gabapentin was ineffective for vascular amputees with pre-existing chronic pain. Venlafaxine decreased pain (including burning and stabbing pain) at 7 days and 6 months after mastectomy. Intravenous and topical local anaesthetics reduced chronic pain after mastectomy, whereas local anaesthetic infiltration was not shown to be effective. Regional analgesia was generally beneficial for chronic symptoms. Ketamine did not reduce the incidence of chronic pain and generally did not help acute pain after amputation or thoracotomy. In 1 of 2 trials, epidural ketamine with bupivacaine reduced acute pain but in neither trail was chronic pain improved. Intercostal cryoanalgesia in thoracotomy generally did not reduce the incidence of acute pain, but interestingly it increased the incidence of chronic pain in 4 out of 5 trials. Total intravenous anaesthesia reduced post-thoracotomy pain in one study. High-dose remifentanil (with a post-operative epidural) did not influence acute pain, but exacerbated chronic pain vs. low-dose remifentanil in a post-thoracotomy study. The authors recommend using this evidence to form a standard approach to patients using drugs to target neuropathic pain in the perioperative management for amputation, thoracotomy and mastectomy.