TY - JOUR T1 - Anatomical description of anaesthetic spread after deep erector spinae block at L-4 JO - Revista Española de Anestesiología y Reanimación (English Edition) T2 - AU - De Lara González,S.J. AU - Pomés,J. AU - Prats-Galino,A. AU - Gracia,J. AU - Martínez-Camacho,A. AU - Sala-Blanch,X. SN - 23411929 M3 - 10.1016/j.redare.2019.07.001 DO - 10.1016/j.redare.2019.07.001 UR - https://www.elsevier.es/en-revista-revista-espanola-anestesiologia-reanimacion-english-444-articulo-anatomical-description-anaesthetic-spread-after-S234119291930126X AB - IntroductionThoracic erector spinae plane (ESP) block is now used for postoperative analgesia. However, although reports of lumbar ESP have been published, the anesthetic spread and mechanism of action of this technique remains unclear. We describe the lumbar ESP block technique and evaluate the spread of 20 ml of solution administered at the level of the transverse process of L4 in a cadaver model. MethodsObservational study after 12 lumbar ESP blocks at L4 on a fresh cadaver model (6 bilaterally). The spread of 20 ml of injected contrast solution was assessed by computed tomography in all 6 samples. Four of the samples were evaluated by anatomical study, 2 by plane dissection, and 2 others were frozen and cut into 2–2.5 cm axial slices. ResultsThe injected solution spread from L2 to L5 in a cranio-caudal direction in the erector spinae muscle, reaching the facet joints medially and the thoracolumbar fascia laterally. In 33% of cases the solution did not spread anterior to the transverse process; in 51%, spread was minimal and did not affect the corresponding spinal nerves, and in 2 samples (16%), spread was extensive and reached the corresponding spinal nerves. ConclusionsLumbar ESP at L4 always acts on the posterior branches of the spinal nerves, but seldom spreads to the paravertebral space to block the spinal nerve. ER -