Hamada J, Fujioka S, Ushio Y
Department of Neurosurgery, Kumamoto University Medical School, Japan.
Neurosurgery. 1993 May;32(5):817-21; discussion 821. doi: 10.1227/00006123-199305000-00015.
To evaluate the usefulness of lumbar intraspinal epidural pressure (ISEDP) measurements for the estimation of intracranial pressure, we studied the relationship between ISEDP and intracranial epidural pressure (ICEDP) in 25 adult mongrel dogs. ICEDP and ISEDP were measured simultaneously with Gaeltec catheter-tip pressure transducers placed in the parietal epidural space and in the lumbar epidural space. Groups 1 and 2 dogs served as normal cerebrospinal fluid condition models. Group 1 received sequential steady-state normal saline infusions (0.5, 1.0, and 1.5 ml/min) into the cisterna magna. ISEDP and ICEDP measurements exhibited a linear correlation, and ISEDP was 80 to 90% of ICEDP at any pressure level. There was no significant difference in the pressure curves obtained at the different infusion rates. Group 2 dogs were subjected to rapid pressure changes by a cisternal bolus injection. Although compliance calculated from the change in ISEDP was slightly greater than that from ICEDP at resting pressure, the compliance calculated from both ISEDP and ICEDP decreased at 20 and 30 mm Hg of ICEDP and the values became almost equivalent. Groups 3 and 4 dogs were mild and severe experimental subarachnoid models, respectively. The ISEDP and ICEDP measurements also showed a linear correlation; however, ISEDP was about 70% of ICEDP in Group 3 and about 50% of ICEDP in Group 4. Although there are varying degrees of discrepancy between ISEDP and ICEDP in the normal or subnormal pressure range and in the presence of severe spinal block, our findings suggest that ISEDP measurements can be used to estimate intracranial pressure in a clinical practice.
为评估腰椎椎管内硬膜外压力（ISEDP）测量在估计颅内压方面的实用性，我们研究了25只成年杂种犬的ISEDP与颅内硬膜外压力（ICEDP）之间的关系。使用Gaeltec导管尖端压力传感器同时测量放置在顶叶硬膜外间隙和腰椎硬膜外间隙的ICEDP和ISEDP。第1组和第2组犬作为正常脑脊液状况模型。第1组犬接受向小脑延髓池依次输注稳态生理盐水（0.5、1.0和1.5 ml/分钟）。ISEDP和ICEDP测量显示出线性相关性，并且在任何压力水平下ISEDP为ICEDP的80%至90%。在不同输注速率下获得的压力曲线无显著差异。第2组犬通过小脑延髓池大剂量注射进行快速压力变化。尽管在静息压力下由ISEDP变化计算出的顺应性略大于由ICEDP计算出的顺应性，但当ICEDP为20和30 mmHg时，由ISEDP和ICEDP计算出的顺应性均降低，且数值几乎相等。第3组和第4组犬分别为轻度和重度实验性蛛网膜下腔模型。ISEDP和ICEDP测量也显示出线性相关性；然而，第3组中ISEDP约为ICEDP的70%，第4组中约为ICEDP的50%。尽管在正常或低于正常压力范围以及存在严重脊髓阻滞的情况下ISEDP与ICEDP之间存在不同程度的差异，但我们的研究结果表明，在临床实践中ISEDP测量可用于估计颅内压。
