Pediatric Regional Anesthesia
Kathleen L. McGinn
KEY POINTS
1. Performing regional blocks in children under general anesthesia has been shown to be safe and is regarded as the standard of care.
2. Pain is often undertreated in infants and children because of erroneous beliefs that it has no harmful long-term effect in this patient population.
3. There is an increased risk of local anesthetic systemic toxicity in infants cause by decreased plasma protein concentration, higher unbound fraction of local anesthetic, slower hepatic metabolism, slightly reduced plasma pseudocholinesterase activity, and decreased methemoglobin-reductase activity.
4. Topical anesthesia can decrease needle pain with intravenous placement or regional blocks, but it requires standard protocols for early placement to ensure adequate time for maximal effectiveness.
5. Caudal block is the most common pediatric regional technique for children up to school age.
6. Ultrasound-guidance for pediatric regional anesthesia facilitates the use of lower local anesthetic volume and greater block placement accuracy.
THE USE OF REGIONAL BLOCKS in pediatric anesthesia has increased dramatically with the advent of ultrasound guidance. However, nerve blocks still tend to be underutilized in children. This can be attributed to fear of neurologic complications, lack of experience, or lack of appropriate pediatric-sized equipment. In pediatric patients, it is standard to perform regional blocks under general anesthesia. The benefit of successful regional anesthesia lies in a more comfortable emergence. In turn, this reduces complications associated with parenteral opioids in vulnerable pediatric patients (neonates, ex-premature infants, and children with cystic fibrosis).
Although regional blocks confer similar advantages in children as in adults, the methods used for performing these techniques must be modified. Expectedly, the key to success lies in knowledge of anatomy, pharmacology, equipment, ultrasound, and preblock sedation or anesthesia. Because general anesthesia/sedation is often required, two individuals are helpful; one to perform the block and the other to monitor the child. All techniques, whether regional or general, carry risks, and the latter must be weighed against the potential benefits in anesthetized children. The current chapter focuses on how pediatric regional techniques differ from their adult counterparts. There exist excellent reviews of pediatric regional anesthetic techniques for readers who wish to pursue the latter in more detail (1,2,3,4).