Success of bedside ultrasound to identify puncture site for spinal anesthesia in neonates and infants.

Spinal anesthesia (SA) may be difficult in small infants. Conceptual advantages of ultrasound imaging to view critical neuraxial structures and exploiting the acoustic window unique to infants have been described but not clinically verified. We present 14 preterm-infants aged 35-48 weeks, weighing 1575-5800 g, and describe ultrasound imaging to locate an appropriate puncture site for SA. The success rate for first puncture was 64%, and the overall success on three attempts was 86%. The mean dural depth was 8 mm (1.6). The inferior medullary cone location was just above L3-L4 in 85.7% of patients. Ultrasound imaging for SA in infants may offer advantages.