Evidence-based clinical update: Which local anesthetic drug for pediatric caudal block provides optimal efficacy with the fewest side effects?

Purpose: The purpose of this evidence-based clinical update is to identify the best evidence when selecting a long-acting local anesthetic agent for single-shot pediatric caudal anesthesia in children.
Methods: A structured literature search was conducted using PubMed and Medline (OVID) using the terms "caudal" and combinations of at least two of "bupivacaine", "ropivacaine", and "levobupivacaine". The search limits included "randomized controlled trials" (RCTs), "meta-analysis", "evidence-based reviews" or "reviews", "human", and "all child: 0-18 yr". Seventeen RCTs were identified that concerned single-shot pediatric caudal anesthesia with at least two of the three drugs in question. Data were extracted for the areas of clinical efficacy and side effects. Study findings were assigned levels of evidence, and grades of recommendation were made according to Centre for Evidence-Based Medicine criteria.
Results: The three drugs investigated were found to be equivalent in terms of efficacy. Evidence showed bupivacaine with the highest incidence of motor block and ropivacaine with the lowest. Adverse effects were rare and unrelated to the choice of drug. There were no serious adverse events.
Conclusion: None of the three agents was shown to be superior in terms of efficacy. Bupivacaine is preferred if motor block is desired, ropivacaine is preferred if motor block is to be minimized. Adverse effects in human studies are rare, mild, and unrelated to the choice of drug. Despite encountering the absence of serious adverse events in each of the studies reviewed, it is noted that animal studies suggest a safer profile with ropivacaine or levobupivacaine than with bupivacaine.