Bedside ultrasound for difficult lumbar puncture.

Lumbar puncture is a common procedure performed in the emergency department for evaluation of several life-threatening conditions, including meningitis and subarachnoid hemorrhage. We describe the use of bedside ultrasound to assist in performance of the lumbar puncture in situations where the standard "blind" technique of needle insertion using palpable spinal landmarks is likely to be difficult or to fail. Use of ultrasound to guide lumbar puncture needle placement was originally reported 30 years ago in the Russian literature. More recently, ultrasound has been used for guiding needle placement for epidural and spinal anesthesia by anesthesiologists and for diagnostic lumbar puncture on infants by radiologists.