"Regional anesthesia in children as commonly performed in the United States has a very low rate of complications," write Dr David M. Polaner of Children's Hospital Colorado, Aurora. At a time of increasing use of regional anesthesia, the study provides reassurance that nerve block procedures are safe for anesthesia or pain control in children.

No Serious Complications of Regional Nerve Blocks

The researchers used a nationwide anesthesiology database, the Pediatric Regional Anesthesia Network, to collect detailed information on regional anesthesia procedures in children, including any complications during and after surgery. The data were "rigorously audited" to identify and correct errors and to ensure that all regional anesthetics performed at the participating hospitals were included.

Regional anesthesia provides a useful approach to anesthesia during surgery or pain control after surgery. As opposed to general anesthesia where the patient inhales an anesthetic gas, regional anesthesia consists of injections of anesthetic drugs around specific nerves to "block" sensation in that part of the body.

The review identified nearly 15,000 regional anesthesia procedures performed between 2007 and 2010. About 11,000 procedures consisted of a single anesthetic injection. The rest were "continuous block" procedures, with insertion of a catheter near the nerve for repeated anesthetic injections.

Although risk varied by the type and location of nerve block, overall complication rates were low. Most importantly, there were no deaths or serious complications leading to permanent injury. For single-injection procedures, the most common complication was inability to place the block or block failure -- two percent of the total.

Continuous block procedures had a higher complication rate -- most commonly problems in catheter placement (such as kinking or dislodgement). In this group, the block failure rate was nine percent.

Increased Use Driven by Ultrasound Guidance

The single most common block (40 percent) was a single-injection block in the pelvic area (caudal block) for procedures in the lower body (for example, hernia surgery). However, blocks of the peripheral nerves were common as well (35 percent), especially for surgery on the upper and lower limbs.

The large numbers of single-injection peripheral nerve blocks seemed related to increased use of ultrasound to guide local anesthetic injections. Ultrasound was used in more than 80 percent of upper-limb blocks and nearly 70 percent of lower-limb blocks.

As the use of regional anesthesia continues to increase, there is a lack of "detailed and complete" information on its safety in children. The best available studies, performed in Europe, are more than a decade old. Thus they may not reflect modern practice, including the use of ultrasound guidance.

Because complications of regional anesthesia are relatively uncommon, very large databases are needed to provide meaningful estimates of the true risks. The new analysis of an extensive, high-quality database suggests that, as in the previous studies from Europe, the complication risk is very low.

Most importantly, the risk of death or serious complications appears minimal, with no such cases in nearly 15,000 procedures over three years. Dr Polaner and coauthors add, "Multicenter collaborative networks such as the Pediatric Regional Anesthesia Network can facilitate the collection of detailed prospective data for research and quality improvement.