ArticleA single infusion of intravenous ketamine improves pain relief in patients with critical limb ischaemia: results of a double blind randomised controlled trialMitchell, Alison C.a,∗; Fallon, Marie T.bAuthor Information aDepartment of Palliative Medicine, Beatson Oncology Centre, Western Infirmary, Glasgow, Scotland G11 6NT, UK bThe Edinburgh Cancer Centre, Western General Hospital, Edinburgh, UK ∗Corresponding author. Tel.: +44-141-211-2411; fax: +44-141-211-6307 Received 19 June 2001; received in revised form 14 January 2002; accepted 17 January 2002. Pain: June 2002 - Volume 97 - Issue 3 - p 275-281 doi: 10.1016/S0304-3959(02)00033-7 Buy Metrics Abstract We report the first double blind randomised controlled trial of regular opioids and an infusion of low dose (0.6 mg/kg) intravenous ketamine compared with opioids and placebo in patients with allodynia, hyperalgesia and hyperpathia secondary to critical limb ischaemia. Thirty-five patients completed the study, 18 received regular opioids plus ketamine, while 17 received regular opioids plus placebo. Using the Brief Pain Inventory, the % pain relief that the patients in the ketamine group attributed to their medication improved significantly from 50% immediately pre-infusion to 65% 24 h post-infusion and 69% 5 days post infusion. Over the same period, the pain relief achieved by the placebo group rose from 58% pre-infusion to 56% 24 h post infusion and then 50% relief 5 days later. This was statistically significant (P<0.05) using both the t-test and the Wilcoxon Rank Sum test. The ketamine group also showed a statistically significant difference 24 h post infusion of the effect of pain on their general activity (P=0.03) and on their enjoyment of life (P=0.004). This study shows that combining a single infusion of low dose ketamine with regular opioid analgesia can result in a significant improvement in pain relief for this patient group. © 2002 Lippincott Williams & Wilkins, Inc.