[Dispersion of lidocaine epidurally administered to dogs positioned on lateral or external decubitus]

ABSTRACT The aim of this study was to clinically verify the dispersion of lidocaine in the epidural space of dogs placed in different positions. Sixteen dogs with an average weight of 17.5 kilograms were used. These were tranquilized with acepromazine, anesthetized with propofol and allocated to two groups: sternal decubitus (GE) and right lateral decubitus (GLD). Both groups received 2% of lidocaine in the volume of 0.25mL/kg and remained in the same position for 20 minutes. The blocking of the pelvic limbs and the extension of it from the seventh lumbar vertebra were evaluated by means of interdigital and paravertebral panniculus clamping. Orchiectomy surgery was then performed. Afterwards, the total blocking time of the pelvic limbs was evaluated. All dogs presented bilateral blocking, with no differences in cranial extension between groups, with a median of 7.5 (1-14) vertebrae for GE and 4 (1-14) for GLD. The blocking time of the right and left limbs were 123 ± 26 and 130 ± 20 minutes for GE, and 120 ± 21 and 121 ± 20 minutes for GLD with no difference between groups or between limbs. It is concluded that the decubitus does not interfere with the epidural lidocaine distribution.

摘要 本研究旨在临床验证不同体位下利多卡因（lidocaine）在犬硬膜外腔（epidural space）中的扩散分布情况。本研究选用16只平均体重为17.5kg的犬只，先以乙酰丙嗪（acepromazine）镇静、丙泊酚（propofol）诱导麻醉，随后分为两组：俯卧组（GE）与右侧卧位组（GLD）。两组均以0.25mL/kg的剂量给予2%利多卡因，并维持对应体位20分钟。通过趾间钳夹试验与椎旁皮褶钳夹试验评估后肢阻滞效果及第7腰椎头侧的阻滞扩散范围，随后实施睾丸摘除术，并记录后肢的总阻滞时长。结果显示，所有受试犬均出现双侧阻滞，两组的头侧阻滞扩散范围无显著差异：俯卧组的阻滞扩散范围中位数为7.5（1~14）个椎体，右侧卧位组为4（1~14）个椎体。俯卧组右后肢与左后肢的阻滞时长分别为123±26分钟、130±20分钟；右侧卧位组右后肢与左后肢的阻滞时长分别为120±21分钟、121±20分钟，组间及肢间均无统计学差异。本研究结论为：体位不会对硬膜外利多卡因的分布产生影响。