Wattwil M, Sundberg A, Arvill A, Lennquist C
Acta Anaesthesiol Scand. 1985 Nov;29(8):849-55. doi: 10.1111/j.1399-6576.1985.tb02309.x.
Circulatory changes during high thoracic epidural anaesthesia (TEA) were studied in nine healthy volunteers by means of echocardiography and systolic time intervals. The subjects also underwent a physical work test with bicycle ergometry. To evaluate the systemic effect of the local anaesthetic (bupivacaine), the same subjects were investigated 3 weeks later when a corresponding dose of the local anaesthetic was injected intramuscularly instead of epidurally. On the first occasion, after baseline measurements an epidural catheter was inserted at T4 level and 5 ml of 0.5% bupivacaine were injected. This volume led to sensory block within dermatomes T1-T5. On the second occasion all subjects received 8 ml of 0.5% bupivacaine intramuscularly. Heart rate (HR) and systolic blood pressure decreased during TEA, both at rest and during exercise. Following i.m. injection, HR decreased at rest but remained unchanged during exercise. The systolic blood pressure was not affected but the diastolic blood pressure increased during the exercise test. After administration of TEA, stroke volume (SV) decreased 22% and cardiac output (CO) 33%. Following i.m. injection of bupivacaine, SV decreased 8% and CO 20%. The pre-ejection period/left ventricular ejection time ratio increased 23% during TEA and 16% after i.m. injection. The results indicate that the circulatory changes did not seem to be caused entirely by the cardiac sympathetic block, but were due partly to the systemic effect of bupivacaine.
通过超声心动图和收缩期时间间期，对9名健康志愿者在高胸段硬膜外麻醉（TEA）期间的循环变化进行了研究。受试者还进行了自行车测力计体力测试。为了评估局部麻醉药（布比卡因）的全身效应，3周后对相同受试者进行了研究，此时将相应剂量的局部麻醉药经肌肉注射而非硬膜外注射。第一次，在基线测量后，于T4水平插入硬膜外导管，并注射5毫升0.5%布比卡因。该剂量导致T1 - T5皮节范围内的感觉阻滞。第二次，所有受试者均接受8毫升0.5%布比卡因肌肉注射。在TEA期间，无论是静息状态还是运动期间，心率（HR）和收缩压均下降。肌肉注射后，静息时HR下降，但运动期间保持不变。收缩压未受影响，但在运动测试期间舒张压升高。给予TEA后，每搏输出量（SV）下降22%，心输出量（CO）下降33%。肌肉注射布比卡因后，SV下降8%，CO下降20%。射血前期/左心室射血时间比值在TEA期间升高23%，肌肉注射后升高16%。结果表明，循环变化似乎并非完全由心脏交感神经阻滞引起，部分是由于布比卡因的全身效应。
