RT Journal Article
SR Electronic
T1 Dose-dependent effects of high intensity focused ultrasound on compound action potentials in an ex vivo rodent peripheral nerve model: comparison to local anesthetics
JF Regional Anesthesia & Pain Medicine
JO Reg Anesth Pain Med
FD BMJ Publishing Group Ltd
SP 242
OP 248
DO 10.1136/rapm-2021-103115
VO 47
IS 4
A1 Anderson, Thomas Anthony
A1 Delgado, Jorge
A1 Sun, Sharon
A1 Behzadian, Negin
A1 Vilches-Moure, Jose
A1 Szlavik, Robert B
A1 Butts-Pauly, Kim
A1 Yeomans, David
YR 2022
UL http://rapm.bmj.com/content/47/4/242.abstract
AB Background In animal models, focused ultrasound can reversibly or permanently inhibit nerve conduction, suggesting a potential role in managing pain. We hypothesized focused ultrasound’s effects on action potential parameters may be similar to those of local anesthetics.Methods In an ex vivo rat sciatic nerve model, action potential amplitude, area under the curve, latency to 10% peak, latency to 100% peak, rate of rise, and half peak width changes were assessed after separately applying increasing focused ultrasound pressures or concentrations of bupivacaine and ropivacaine. Focused ultrasound’s effects on nerve structure were examined histologically.Results Increasing focused ultrasound pressures decreased action potential amplitude, area under the curve, and rate of rise, increased latency to 10% peak, and did not change latency to 100% peak or half peak width. Increasing local anesthetic concentrations decreased action potential amplitude, area under the curve, and rate of rise and increased latency to 10% peak, latency to 100% peak, and half peak width. At the highest focused ultrasound pressures, nerve architecture was altered compared with controls.Discussion While some action potential parameters were altered comparably by focused ultrasound and local anesthetics, there were small but notable differences. It is not evident if these differences may lead to differences in clinical pain effects when focused ultrasound is applied in vivo or if focused ultrasound pressures that result in clinically relevant changes damage nerve structures. Given the potential advantages of a non-invasive technique for managing pain conditions, further investigation may be warranted in an in vivo pain model.Data are available on reasonable request.