Imawaki S
Acta Med Okayama. 1987 Jun;41(3):105-16. doi: 10.18926/AMO/31760.
The extra-anatomical bypass formation and the exclusion of thoracic aortic aneurysms by the "paired clamp method" applied to the thoracic aorta of mongrel dogs, and the development of hind leg paralysis was studied experimentally in relation to the ratio between the mean excluded cavity pressure and the mean aortic pressure ratio (EA-ratio). The relationship between thrombus formation in the excluded cavity and the EA-ratio was also studied. Animals were divided into 4 groups: Group 1 underwent the cross-clamping of the descending thoracic aorta for 8 min; Group 2 underwent exclusion of the entire thoracic aorta under permanent bypass; Group 3 underwent ligation of 2/3 of the proximal intercostal arteries which branched from the excluded thoracic aorta; and Group 4 underwent division of the excluded thoracic aorta into 3 parts by ligation. No animals in group 1 developed paralysis. When EA-ratios were higher than 0.48, animals in groups 2 and 3 were not paralyzed, whereas all but 1 animals with EA-ratios lower than or equal to 0.48 were paralyzed. There was statistically significant difference between the EA-ratio of the non-paralyzed animals and that of the paralyzed animals in groups 2 and 3. Four out of 5 animals in group 4 were paralyzed. However, there was no statistically significant difference between the EA-ratio in these 4 paralyzed animals and that in the non-paralyzed animals in groups 2 and 3. When the EA-ratio was lower than or equal to 0.59, all but 1 excluded cavities of groups 2 and 3 animals were fully thrombosed 7 or 8 days after the operation. None of these animals showed the aggravation of the paralysis during the observation period and, conversely, the paralysis of almost all animals was ameliorated. These results suggested that the EA-ratio is useful in predicting the development of paralysis and thrombus formation in the excluded cavity after the operation of thoracic aortic aneurysms by the "paired clamp method".
采用“双钳法”对杂种犬胸主动脉进行胸主动脉瘤的体外旁路形成和瘤体排除，并通过实验研究了后肢麻痹的发生与平均排除腔压力与平均主动脉压力比值（EA比值）之间的关系。还研究了排除腔内血栓形成与EA比值之间的关系。将动物分为4组：第1组对胸降主动脉进行8分钟的交叉钳夹；第2组在永久性旁路下排除整个胸主动脉；第3组结扎从被排除的胸主动脉分支的2/3近端肋间动脉；第4组通过结扎将被排除的胸主动脉分成3部分。第1组没有动物发生麻痹。当EA比值高于0.48时，第2组和第3组的动物没有麻痹，而EA比值低于或等于0.48的动物中，除1只外全部发生麻痹。第2组和第3组中未麻痹动物与麻痹动物的EA比值之间存在统计学显著差异。第4组的5只动物中有4只发生麻痹。然而，这4只麻痹动物的EA比值与第2组和第3组未麻痹动物的EA比值之间没有统计学显著差异。当EA比值低于或等于0.59时，第2组和第3组动物在术后7或8天，除1个排除腔外，其余全部完全血栓形成。在观察期内，这些动物均未出现麻痹加重的情况，相反，几乎所有动物的麻痹都有所改善。这些结果表明，EA比值有助于预测“双钳法”治疗胸主动脉瘤术后排除腔内麻痹和血栓形成的发生情况。
