The caudal block is the most commonly performed regional anesthesia technique in children. Unfortunately, there is little data available to support the safety of the procedure. The Pediatric Regional Anesthesia Network (PRAN) database was created in order to fill gaps in available knowledge about the safety of regional anesthesia in children by collecting large-scale statistics.
Founded under the auspices of the Society for Pediatric Anesthesia, PRAN is a collection of observational data from multiple study sites around the country and abroad. In this month’s issue of Anesthesia & Analgesia, Dr. Santhanam Suresh, Department of Anesthesiology, Northwestern University, Chicago, Illinois, and coauthors from the Department of Anesthesiology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Northwestern University, Chicago, Illinois, analyzed the outcome of caudal blocks in 18,650 children over a five-year period in the article titled “Are Caudal Blocks for Pain Control Safe in Children? An Analysis of 18,650 Caudal Blocks from the Pediatric Regional Anesthesia Network (PRAN) Database.”
The authors found a 1.9% complication rate. The most common complications included block failure, blood aspiration, and intravascular injection. Although some have hypothesized that there may be a higher risk of complications in children due to block placement under general anesthesia, after adjusting for age, blocks performed with the patient under general anesthesia did not have a higher incidence of complications compared to blocks performed in awake patients. Interestingly, the rate of complications did not differ between blocks performed with ultrasound guidance and blocks performed without ultrasound guidance. In fact, as the study progressed, the use of ultrasound for block placement decreased.
The authors found significant variability in local anesthetic dosing, including a significant number of patients (4,406 of 17,867) receiving doses of bupivacaine over 2 mg/kg. That exceeds the dose that the authors considered safe. However, there were no cases of local anesthetic toxicity documented. Most importantly, there were no temporary or permanent sequelae related to caudal block that were recorded. As the authors note, this was a study of safety, not efficacy.
In the accompanying editorial titled ““Kiddie” Caudal: Safe but More to Learn,” authors Dr. James A. DiNardo and Dr. Karen R. Boretsky from the Department of Anesthesia, Boston Children’s Hospital, Boston, Massachusetts, argue for further study. Using data from the large PRAN database, they note that it was demonstrated that epidural analgesia administered via the caudal space, the “kiddie caudal,” is remarkably safe. However, due to the inability of the database to capture highly detailed information, important questions regarding local anesthetic dose variation, block failure, and safe total local anesthetic doses remain unanswered.