Department of Electrical and Computer Engineering, University of British Columbia, 2332 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
Department of Anesthesiology, Vancouver General Hospital, Vancouver, BC, Canada.
Can J Anaesth. 2020 Sep;67(9):1152-1161. doi: 10.1007/s12630-020-01734-0. Epub 2020 Jun 4.
Optimizing patient position and needle puncture site are important factors for successful neuraxial anesthesia. Two paramedian approaches are commonly utilized and we sought to determine whether variations of the seated position would increase the chance of puncture success.
We simulated paramedian needle passes on three-dimensional lumbar spine models registered to volumetric ultrasound data acquired from ten healthy volunteers in three different positions: 1) prone; 2) seated with thoracic and lumbar flexion; and 3) seated as in position 2, but with a 10° dorsal tilt. Simulated paramedian needle passes from the right side performed on validated models were used to determine L2-3 and L3-4 neuraxial target size and success. We selected two paramedian puncture sites according to standard anesthesia textbook descriptions: 10 mm lateral and 10 mm caudal from inferior edge of the superior spinous process as described by Miller, and 10 mm lateral from the superior edge of the inferior spinous process as described by Barash.
A significant increase in the area available for dural puncture was found in the L2-3 (61-62 mm) and L3-4 (76-79 mm) vertebral levels for all seated positions relative to the prone position (P < 0.001). Similarly, a significant increase in the total number of successful punctures was found in the L2-3 (77-79) and L3-4 (119-120) vertebral levels for all seated positions relative to the prone position (P < 0.001). No differences were found between seated positions. The Barash puncture site achieved a higher number of successful punctures than the Miller puncture site in both the L2-3 (19) and L3-4 (84) vertebral levels (P < 0.001).
An added dorsal table tilt did not increase puncture success in the seated position. The landmarks for puncture site described by Barash resulted in significantly more successful punctures compared with those described by Miller in all positions.
优化患者体位和穿刺部位是成功进行脊神经麻醉的重要因素。两种旁正中入路方法通常被使用，我们试图确定坐立位的变化是否会增加穿刺成功的机会。
我们在三个不同的位置对十名健康志愿者的容积超声数据进行了三维腰椎模型的模拟旁正中进针：1）俯卧位；2）胸腰椎弯曲的坐位；3）如位置 2 但背部倾斜 10°的坐位。从验证过的模型上从右侧进行模拟旁正中进针，以确定 L2-3 和 L3-4 脊神经麻醉的目标大小和成功率。我们根据标准麻醉教科书的描述选择了两个旁正中穿刺点：10mm 侧方和 10mm 尾侧距上棘突下边缘，如 Miller 所述；以及 10mm 侧方距下棘突上边缘，如 Barash 所述。
与俯卧位相比，所有坐位时 L2-3（61-62mm）和 L3-4（76-79mm）椎体水平的硬脑膜穿刺可用面积显著增加（P <0.001）。同样，与俯卧位相比，所有坐位时 L2-3（77-79）和 L3-4（119-120）椎体水平的总穿刺成功率显著增加（P <0.001）。坐位之间没有差异。Barash 穿刺点在 L2-3（19）和 L3-4（84）椎体水平的穿刺成功率均高于 Miller 穿刺点（P <0.001）。
在坐立位时，增加背部倾斜角度并未增加穿刺成功率。与 Miller 描述的穿刺点相比，Barash 描述的穿刺点在所有体位下都能显著提高穿刺成功率。
