Pediatric Regional Anesthesia and Pain Management
Regional techniques
Pediatric regional anesthesia is safe and opioid-sparing when dosing is weight-based and anatomy is respected. Common blocks include caudal, ilioinguinal/iliohypogastric, penile, transversus abdominis plane, erector spinae, and upper/lower extremity blocks. Ultrasound improves success and reduces local anesthetic volume.
Key principles
- Local anesthetic ceilings: bupivacaine ~2–2.5 mg/kg (lower in neonates), ropivacaine ~2–3 mg/kg; add epinephrine to detect intravascular injection and prolong block.
- Caudal block: landmark or ultrasound-guided; watch for intravascular or intrathecal injection; avoid in sacral anomalies.
- Adjuvants: clonidine and dexmedetomidine prolong caudal analgesia; dexamethasone may prolong peripheral blocks.
- Multimodal analgesia: acetaminophen and NSAIDs are first-line; opioids for breakthrough; PCA for older children.
- Pain assessment: use age-appropriate scales (FLACC, Wong-Baker, numeric rating); neonates require validated tools and gentle handling.
Traps
Questions often test the maximum dose of bupivacaine in an infant - it is lower than in adults because of reduced clearance. Another trap is missing that a caudal block can mask a developing complication (e.g., compartment syndrome) or that epinephrine-containing solutions should not be used near end-arterial digits in some protocols.
Rule of thumb
Calculate the total local anesthetic dose by weight before adding any adjuvant, and never exceed the ceiling even if the block "looks small."
Worked example
A 10 kg infant for inguinal hernia repair. Bupivacaine 0.25% at 2 mg/kg = 20 mg = 8 mL. Add clonidine 1–2 mcg/kg to prolong analgesia; supplement with acetaminophen and NSAID. Monitor for local anesthetic systemic toxicity (LAST) - treat with lipid emulsion if seizures or arrhythmia occur.