Patient-Controlled Analgesia Plus Background Opioid Infusion for Postoperative Pain in Children: A Systematic Review and Meta-Analysis of Randomized Trials.

BACKGROUND: Bolus administration of opioids via a patient-controlled analgesia (PCA) device is widely used in the postoperative pediatric population. PCA devices have been shown to provide superior analgesia and greater patient satisfaction compared with intermittent administration. Studies comparing the efficacy of PCA with and without a background infusion for postoperative analgesia in children vary considerably in terms of dosing and methodologic quality, making it difficult for practitioners to derive clinically useful information. The purpose of this meta-analysis was to assess whether the addition of a background infusion to PCA bolus administration of an opioid analgesic is more effective (defined as lower pain scores) than PCA bolus alone in the postoperative population specific to children.
METHODS: We searched Medline, Embase, and CENTRAL from inception to January 2015 for registered and ongoing trials included in the meta-Register of Controlled Trials and ClinicalTrials.gov, and reference lists of review articles and included articles. Study selection was randomized controlled studies comparing PCA bolus with PCA bolus plus background infusion for postoperative analgesia in children aged 0 to 18 years and adolescents aged 13 to 21 years undergoing any form of surgery that used patient-reported pain scores as an outcome measure. Two reviewers independently extracted data on patient and study characteristics, interventions, and outcomes from included studies using standardized data extraction forms. Seven trials met our eligibility criteria. Data were analyzed using Review Manager version 5.3. Meta-analyses were performed for outcomes that were defined similarly and reported in 2 or more studies, including patient-reported pain scores, nausea and/or vomiting, sedation, and opioid consumption. We independently assessed the risk of bias for each outcome and the certainty in the estimates of effect for critically important outcomes (pain scores, nausea and/or vomiting, excessive sedation) using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Subgroup analyses based on dose of background infusion (high versus low dose) and risk of bias (low versus high/unclear) were performed.
RESULTS: There were no significant differences found with respect to pain scores 12 and 24 hours after surgery, opioid consumption, or risk of adverse events with the addition of a background opioid infusion to PCA opioid bolus doses. The quality of the evidence was deemed to be low to very low.
CONCLUSIONS: There was no significant difference in outcomes with the addition of an opioid background infusion to PCA bolus doses of opioid. Further high-quality studies are required.