Perioperative ketamine does not prevent chronic pain after thoracotomy.

Thoracotomy is often responsible for chronic pain, possibly of neuropathic origin. To confirm preclinical studies, the preventive effects of perioperative ketamine were tested in a randomized, double-blind, placebo-controlled clinical trial on persistent neuropathic pain after thoracotomy. Eighty-six patients scheduled for thoracotomy under standardised general anaesthesia were randomised to receive either ketamine (1 mg kg(-1) at the induction, 1 mg kg(-1) h(-1) during surgery, then 1 mg kg(-1) during 24 h; n=42) or normal saline (n=44).