Real-Time Ultrasound Improves Accuracy of Caudal Block in Children

Abstract

BACKGROUND: Caudal block, the most common regional anesthetic in children, is predominantly performed using palpation to determine placement. The efficacy of the palpation technique is unknown with respect to block success. While ultrasound has been suggested for use during caudal block, its use is infrequent. METHODS: A single-blinded prospective observational trial was performed evaluating provider success rate of caudal blocks placed by palpation alone. After needle insertion and partial local anesthetic injection, an ultrasound was performed to confirm correct location. RESULTS: A total of 109 caudal blocks were performed during the prospective observational study. Success rate for caudal blocks done by palpation alone was 78.9% as confirmed by ultrasound. In 21.1% of caudal blocks, the provider incorrectly judged the needle to be in the caudal space as confirmed with ultrasound. CONCLUSIONS: Real-time ultrasound visualization of local anesthetic injection provides reliable and immediate confirmation during caudal block in children.

Confirmation of success rate of landmark‐based caudal blockade in children using ultrasound: A prospective analysis

“…This study and a larger recent study by Adler et al demonstrate a failure rate of 20 and 21.1%, respectively, when landmark palpation technique is used alone for placement of caudal in infants and children and that ultrasound‐imaging provides an objective assessment of caudal needle location or presence of injected saline/ local anesthetic 9 . While ultrasound use has increased the accuracy and safety for the placement of many regional anesthetics in children, the Pediatric Regional Anesthesia Network (PRAN) reports that ultrasound is used in only 3% of caudal blocks in children 1 .…”

“…The routine use of ultrasound to confirm ultimate LA location would, however, improve overall success rates with improvements in patient care. Adler was able to demonstrate decreased use of rescue opioids in the recovery room when ultrasound was used to confirm proper placement 9 . This is especially relevant as infants and younger children, the target population for caudals, are more susceptible to opioid‐induced respiratory depression 16 …”

“…While these endpoints may be suggestive of success, none are objectively confirmatory. A recent paper by Adler et al demonstrates a 21.1% technical failure rate for caudal blocks done by palpation alone when using ultrasound‐imaging for confirmation 9 …”

“…Ultrasound‐guided confirmation can provide an objective assessment of caudal needle location and LA administration and has the potential to improve the efficacy and safety of caudal blockade when compared to landmark techniques alone, 9‐12 yet is used in as few as 3% of pediatric caudal placements 1 . Incomplete bone ossification in infants and young children creates acoustic windows making ultrasound‐imaging of the central neuraxis easier than in older patients 13 .…”

Ultrasound determination of the dural sac to sacrococcygeal membrane distance in premature neonates

“…Ultrasound has been used to identify low lying dural sacs 6 7. Visualization of the neonatal sacral anatomy improves caudal success rates but no systematic studies have determined the feasibility of locating the dural sac using real-time imaging 8 9. The primary goal of this study was to determine the feasibility of measuring the distance from the sacrococcygeal membrane at the cephalad most edge of the sacral hiatus to the caudal edge of the dural sac in a preterm neonatal population using ultrasound-imaging.…”