Ketamine for perioperative pain management in children: a meta-analysis of published studies.

INTRODUCTION Balanced analgesia, using both opioid and nonopioids agents, has become the standard care for postoperative pain management. Ketamine, a compound with analgesic and antihyperalgesic properties, has been shown to decrease postoperative pain and opioid requirements in adults. The goal of the present meta-analysis was to investigate postoperative analgesic properties of ketamine in pediatric patients. MATERIAL AND METHODS A comprehensive literature search was conducted to identify clinical trials that used ketamine as a perioperative analgesic compound in children and infants. Outcomes measured were postoperative analgesic consumption, pain intensity and duration of sensory block (when ketamine was used by caudal route) during the postoperative care unit (PACU) stay and the early postoperative period (6-24 h after leaving the operative room). The data from each trial were combined to calculate the pooled odds ratios or standard mean differences and their 95% confidence intervals. RESULTS Thirty-five randomized, blinded controlled studies were retrieved from the literature. Systemic ketamine was effective in decreasing PACU pain intensity and analgesic requirement but failed to influence early (6-24 h) pain intensity and analgesic requirement. Ketamine administered locally during tonsillectomy, decreased PACU and early (6-24 h) pain intensity and PACU analgesic requirements. Used as an adjuvant for caudal analgesia, ketamine increased the duration of sensory block and PACU analgesic requirement without impacting PACU pain intensity. Ketamine failed to exhibit a postoperative opioid-sparing effect. CONCLUSIONS This meta-analysis found that administration of ketamine was associated with decreased PACU postoperative pain intensity and nonopioid analgesic requirement. However, ketamine failed to exhibit a postoperative opioid-sparing effect.