Walker, B.J. (2017) Journal of Clinical Anesthesia. 38(5) pp. 158–159
Prior to the widespread use of ultrasound guidance in regional anesthesia, higher volumes of local anesthetic were often required to achieve reliable blockade with landmark and neurostimulation techniques.
The ability to clearly visualize neural structures with ultrasound guidance has resulted in more precise delivery of local anesthetic around the target nerve or plexus, which should theoretically reduce the risk of complications such as local anesthetic systemic toxicity (LAST) as well as tissue toxicity to nerves and surrounding muscle.
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