Ultrasonography as a preoperative assessment tool: predicting the feasibility of central neuraxial blockade.

A woman with severe ankylosing spondylitis presented to the preanesthetic clinic before total hip arthroplasty. She had required general anesthesia with fiberoptic intubation after failed attempts at spinal anesthesia for previous hip surgery. Using a portable ultrasound unit, we identified an open L4-5 interlaminar space and offered the patient an ultrasound-guided spinal anesthetic. Dural puncture with a single needle pass was subsequently achieved with the aid of preprocedural ultrasound imaging. Ultrasound may be a useful preoperative assessment tool for assessing the feasibility of central neuraxial blockade when technical difficulty is anticipated.