Correspondence  |   June 2019
Ultrasound-guided Popliteal Intraneural Approach: Comment
Author Notes
  • University of Utah School of Health Sciences, Salt Lake City, Utah (J.J.D.). Jennifer.davis@hsc.utah.edu
  • (Accepted for publication March 6, 2019.)
    (Accepted for publication March 6, 2019.)×
Article Information
Correspondence
Correspondence   |   June 2019
Ultrasound-guided Popliteal Intraneural Approach: Comment
Anesthesiology 6 2019, Vol.130, 1082-1083. doi:10.1097/ALN.0000000000002716
Anesthesiology 6 2019, Vol.130, 1082-1083. doi:10.1097/ALN.0000000000002716
We read the recent publication by Cappelleri et al.1  with concern and disappointment. Our concern was for the patients who were intentionally subjected to a procedure known to cause nerve injury,2  and our disappointment was in the rationalization used by the authors to justify this practice.
In this study, Cappelleri et al. claim that intraneural sciatic nerve injection poses no greater risk than extraneural injection. This claim is based on the authors’ previous work published from 2016.2  In that study, the investigators compared nerve conduction for patients who had received what they classified as intraneural and extraneural injection of the sciatic nerve. They report that “both techniques resulted in similar, significant reduction of action potential 5 weeks after surgery compared to baseline.”2  However, in this 2016 study, the needle tip position for so-called extraneural (also referred to as subparaneural) technique was so similar to the intraneural position that the investigators inadvertently performed intraneural injection on 22% of the extraneural study patients. This is a markedly different concept than what is generally considered to be extraneural.1  The outcomes reported from their 2016 study have yet to be reproduced by other investigators. Most anesthesiologists proficient at ultrasound-guided regional anesthesia have adopted techniques for sciatic nerve block that do not require immediate proximity to the nerve.