Subdural injection: what's the gold standard?
Subdural injection: what's the gold standard?
复制标题
硬膜下注射：金标准是什么？
DOI：
10.1097/aap.0b013e31819268a0
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发表时间：
2009
影响因子：
5.1
通讯作者：
Mark,Leighton
中科院分区：
文献类型：
--
作者：
Hogan,QuinnH;Mark,Leighton
硬膜外麻醉是一种信仰。我们通常在没有放射学指导的情况下将硬膜外穿刺针插入由推断而不是直接见证的终点确定的深度。通过的导管不能转向，但只能通过推进距离的单个参数进行控制。注入溶液的分布同样不受直接控制，除了注入多少的单个参数。除了这些考虑，硬膜外腔的内容物是高度异质性的，1，2因此可以理解麻醉效果是可变的。可能包括麻醉剂扩散过度或不足、短暂麻醉持续时间、过度血流动力学变化和可变运动阻滞。当一个特定病例的实际情况超出预期可能性的范围时，一个好的临床医生会考虑病理生理学的选择，对预期硬膜外麻醉的异常反应的一个解剖学解释是溶液错误地进入硬膜下腔。与固定标本中存在的坚硬组织不同，天然蛛网膜是一种非实质性的弹性膜，放射科医生被教导通过使用针的扭转运动来干净地穿刺。这种屈服的一致性解释了硬脑膜被完全穿透但蛛网膜没有被穿透的事件。虽然目前还不清楚针尖或导管在这个空间中的频率，但很有可能是这样。当在脊髓造影的荧光透视期间观察时，注入该平面的溶液以层状方式扩散，通常具有比在具有类似体积的硬膜外腔中发生的更大的纵向范围。由于分层溶液也紧密应用于蛛网膜下腔，因此可以预期临床事件可能与常规硬膜外麻醉剂中的临床事件有很大不同。
Epidural anesthesia is an act of faith. We insert the epidural needle, typically without radiological guidance, to a depth that is determined by inferred rather than directly witnessed endpoints. A catheter is passed that cannot be steered but can only be controlled by the single parameter of how far it is advanced. The distribution of the injected solution is likewise not under direct control except by the single parameter of how much is injected. In addition to these considerations, the contents of the epidural space are highly heterogenous, 1, 2 so it is understandable that the anesthetic effect is variable. Possibilities include excessive or inadequate anesthetic spread, brief anesthetic duration, excessive hemodynamic changes, and variable motor block. When the actual events in a particular case fall outside the range of expected possibilities, a good clinician will ponder the pathophysiological options.One anatomic explanation for aberrant responses to intended epidural anesthesia is delivery of the solution mistakenly into the subdural space. Unlike the stiff tissue present in fixed specimens, the natural arachnoid membrane is an insubstantial and elastic film that radiologists are taught to puncture cleanly by employing a twisting motion of the needle. This yielding consistency accounts for events in which the dura is cleanly penetrated but the arachnoid is not. Although it is unknown how often needle tips or catheters end up in this space, it is highly likely that some do. When witnessed during fluoroscopy for myelography, solution injected into this plane spreads in a laminar fashion, typically with a greater longitudinal extent than would occur in the epidural space with a similar volume. Since the layered solution is also closely applied to the subarachnoid space, it can be expected that clinical events may differ substantially from those in a customary epidural anesthetic.