Department of Anaesthesiology and Intensive Care Therapy, Philipps University Marburg, Marburg, Germany.
Acta Anaesthesiol Scand. 2010 Sep;54(8):993-9. doi: 10.1111/j.1399-6576.2010.02279.x.
In the case of needle nerve contact during peripheral blocks, pencil point needles are considered less traumatic compared with bevelled needles. However, there are not enough data to prove this notion. Therefore, the aim of this study was to challenge the hypothesis that nerve perforation with short bevelled needles is associated with major nerve damage compared with pencil point needles.
In five anaesthetised pigs, the brachial plexus was exposed bilaterally. Up to eight nerves underwent needle nerve perforation using a pencil point needles cannula or an short bevelled needle. After 48 h, the nerves were resected. The specimens were processed for visual examination and the detection of inflammatory cells (haematoxylin-eosin, i.e. CD68-immunohistochemistry to detect macrophages), myelin damage (Kluver-Barrera staining) and intraneural haematoma. The grade of nerve injury was characterised by an objective score ranging from 0 (no injury) to 4 (severe injury).
Fifty nerves were examined. According to the injury score applied, there was no significant difference between the pencil point needles [median (inter-quartile range) 2.0 (2.0-2.0)] and the short bevelled-needle group [median 2.0 (2.0-2.0) P=0.23]. No myelin damage was observed. Signs of post-traumatic inflammation were equally distributed among both groups.
In the present study, the magnitude of nerve injury after needle nerve perforation was not related to one of the applied needle types. Post-traumatic inflammation rather than structural damage of nerve tissue is the only notable sign of nerve injury after needle nerve perforation with either needle type. However, neither the pencil point- nor the short bevelled needle can be designated a less traumatic device.
在周围阻滞时发生针与神经接触的情况下，与斜面针相比，笔尖针被认为对神经的创伤较小。然而，目前还没有足够的数据来证明这一观点。因此，本研究的目的是验证以下假设，即与笔尖针相比，短斜面针穿刺神经会导致更严重的神经损伤。
在 5 只麻醉的猪中，双侧暴露臂丛神经。使用笔尖针套管或短斜面针对 8 根神经进行针与神经穿刺。48 小时后，切除神经。对标本进行肉眼检查，并检测炎症细胞（苏木精-伊红染色，即检测巨噬细胞的 CD68-免疫组化）、髓鞘损伤（Klüver-Barrera 染色）和神经内血肿。采用 0 到 4 分的客观评分来描述神经损伤程度（0 分表示无损伤，4 分表示严重损伤）。
共检查了 50 根神经。根据应用的损伤评分，笔尖针组[中位数（四分位数间距）2.0（2.0-2.0）]和短斜面针组[中位数 2.0（2.0-2.0），P=0.23]之间没有显著差异。未观察到髓鞘损伤。创伤后炎症的迹象在两组之间分布均匀。
在本研究中，神经穿刺后神经损伤的程度与应用的针型无关。创伤后炎症而不是神经组织的结构损伤是针穿刺神经后唯一明显的神经损伤迹象，无论使用笔尖针还是短斜面针，都不能将其指定为创伤较小的器械。
