SummaryWe allocated 100 patients scheduled for day-case knee arthroscopy to unilateral spinal anaesthesia with 40 mg intrathecal hyperbaric prilocaine or to ultrasound-guided femoral-sciatic nerve blockade with 25 ml mepivacaine 2%, 50 participants each. 290-395 [190-440]) min after peripheral nerve blockade, p = 0.016. There was no difference in time from anaesthetic preparation to readiness for surgery.

In ultrasound-guided popliteal sciatic nerve block, intraneural injection provided a faster onset and better success rate compared with subparaneural. Both techniques resulted in a similar subclinical reduction in amplitude of the sciatic action potentials at 5 weeks after surgery. These findings should not be extended to other approaches.

No abstract