Anest. intenziv. Med. 2020;31(5):206-211 | DOI: 10.36290/aim.2020.051

Low volume distal sciatic block (LVDSB) - comparison spread of injectate between LVSDB and distal adductor canal in healthy volunteerOriginal Article

Nalos D., Beňo L., Bejšovec D.

Klinika anesteziologie, perioperační a intenzivní medicíny Univerzita J. E. Purkyně v Ústí nad Labem, Masarykova nemocnice v Ústí nad Labem

Study objective: The aim of the study is to compare two different approaches to the blockade of the popliteal area by evaluating the distribution of an aqueous solution of salt in one volunteer. Type of study: Short technical report. Site type: Department of Anesthesiology, Perioperative and Intenzive Medicine. Material and method: In a volunteer, we simulated two alternative regional blocks, simultaneously, one on each lower limb. On the left leg a simulation of the low volume block of the distal part of the sciatic nerve (LVDSB) was performed by applying 6 ml of 0.9% NaCl solution. Subsequently, on the right leg, simulation of the distal adductor canal block was performed by applying 20 ml of the same solution. Immediately after application CT scans of both popliteal areas including 3D reconstruction was performed.

Results: The analysis of distribution of the solution, by means of computed tomography, after application of a low-volume block (6 ml) to the distal part of the sciatic nerve (LVDSB) shows the spread of fluid to the area of genicular nerves originating from the sciatic nerve. The fluid applied to the distal part of the adductor canal tends to predominantly penetrate retrograde into the thigh area. In the distal direction, the fluid is spreading both along n. saphenus and in medial direction, where it reached the inner edge of the vascular bundle between the adductors. However, it does not spread to the space where genicular branches originate from the sciatic, tibial and fibular nerves.

Conclusion: After LVDSB, the distribution of local anesthetic to the genicular nerve region of the sciatic nerve occurs. The aqueous solution administered through the distal end of the adductor canal does not cover the entire area of the "popliteal" plexus and is unlikely to be able to provide a comparable level of analgesia.

Keywords: regional anesthesia, popliteal fossa, ultrasound.

Published: November 30, 2020  Show citation