Pediatric regional anesthesiology is growing up quickly. Not long ago, the practice of pediatric regional anesthesiology was limited to central (caudal, epidural and spinal) blocks. Today, pediatric anesthesiologists at our center routinely use all kinds of peripheral nerve blocks on pediatric patients—including femoral nerve, sciatic, fascia iliaca compartment, axillary nerve, infraclavicular, parascalene, dorsal penile, ilioinguinal/iliohypogastric (ILIH), and even paravertebral nerve blocks.
The results are excellent; we observe many of the same benefits in children as we do in adults. Regional anesthesia improves post-op analgesia, reduces the need for parenteral opioids (which can contribute to respiratory depression in children and infants) and decreases the intraoperative requirement for general anesthetics. This hastens emergence, speeds overall recovery, and reduces PONV, which is especially important in children, who have a higher PONV rate than adults. It also helps us avoid the central blocks and their undesirable effects—including urinary retention, hypotension, bilateral lower extremity muscle weakness, and other less common but more serious sequelae.
Pediatric peripheral nerve blocks do require specialized skills. Anesthesiologists must be able to perform adult regional blocks before performing them in pediatric patients. They must understand the “miniaturized” pediatric anatomy, which leaves less room for error. Slow, incremental dosing and strict adherence to maximum dosing guidelines are also critical because younger children, especially infants, have a higher risk of local anesthetic toxicity. All children typically have a higher cardiac output and regional blood flow, which results in a rapid increase in blood levels of local anesthetic, and infants are at even greater risk of toxicity due in part to their immature hepatic metabolism.
The anesthesiologist must also approach these blocks with great care. Since pediatric patients require deep sedation or general anesthesia before block placement, the anesthesiologist cannot intentionally elicit paresthesia to target the injection site (a historically common practice in adults), and anesthetized children cannot provide feedback in case of inadvertent intravascular or intraneural injection. As a result, we monitor patients carefully, using test dosing, incremental injections, and meticulous attention to the electrocardiogram for ST-T wave changes. We also routinely use nerve stimulators to target the injection site and inject slowly with attention to any resistance or heart rate increase that may warn of intraneural placement. Several large-scale research papers show that, when approached with the proper expertise, placing blocks in fully anesthetized patients does not increase the risk of complications.
When anesthesiologists are well-trained and practice regional anesthesia with safety in mind, they can perform peripheral nerve blocks in even the youngest patients. At Duke, this is our routine practice, and we have seen a world of difference in post-op recovery time, patient comfort and overall satisfaction.
Dr. Ross is Associate Chief with the Division of Pediatric Anesthesia at Duke University Medical Center, Durham, N.C.