Iselin-Chaves I A, Van Gessel E F, Donald F A, Forster A, Gamulin Z
Départment APSIC, Hôpital Cantonal Universitaire, Geneva, Switzerland.
Anesth Analg. 1996 Oct;83(4):755-9. doi: 10.1097/00000539-199610000-00017.
In a search of a differential spinal block between dependent and nondependent sides, we investigated whether the use of a larger concentration of hyperbaric tetracaine (T) and/or the omission of epinephrine (E) would provide differential spread in patients left for 15 min in the lateral decubitus position. Spinal anesthesia was performed in the lateral decubitus position with the operated side dependent in 60 patients scheduled for lower limb surgery. All patients remained lateral for 15 min after spinal injection before being turned supine. They received 12 mg of T in 10% dextrose and E 0.2 mg was added when predicted duration of surgery was more than 90 min. The concentration of T to be used for each patient was randomized. This resulted in four groups of 15 patients: T 0.5% + E (control group), T 1% + E, T 0.5%, and T 1%. A unilateral anesthesia was defined as the presence of an adequate sensory (L-1 or higher) and/or motor (3 degrees) blockade on the dependent side and the absence of one or both modalities on the nondependent side, or as a duration of sensory (regression to L-2) and motor (1 degrees of recovery) blockade 20% longer on the dependent compared to the nondependent side. None of the 60 patients showed unilateral sensory block. A comparable number of patients in all groups showed unilateral motor block: four in T 0.5% + E, two in T 1% + E, four in T 0.5%, and five in T 1%. Likewise, a comparable number of patients in all groups showed a prolonged duration of sensory and motor block, respectively: six and eight in T 0.5% + E, six and nine in T 1% + E, six and eight in T 0.5%, and seven and seven in T 1%. In conclusion, although a preferential distribution of hyperbaric T toward the dependent side in patients of all four groups was noticed, the use of a larger concentration of T, omission of E, or combination of these two factors did not provide a more marked differential spread when compared to the standard solution of T 0.5% + E.
为了探究脊柱依赖侧和非依赖侧之间的差异性阻滞，我们研究了在侧卧位保持15分钟的患者中，使用更高浓度的重比重丁卡因（T）和/或省略肾上腺素（E）是否会导致差异性扩散。对60例计划进行下肢手术的患者，在侧卧位下进行脊髓麻醉，手术侧在下。脊髓注射后，所有患者保持侧卧位15分钟，然后转为仰卧位。他们接受12毫克丁卡因溶于10%葡萄糖溶液中，当预计手术时间超过90分钟时加入0.2毫克肾上腺素。每位患者使用的丁卡因浓度是随机分配的。这产生了四组，每组15例患者：T 0.5% + E（对照组）、T 1% + E、T 0.5%和T 1%。单侧麻醉的定义为依赖侧存在足够的感觉（L-1或更高）和/或运动（3级）阻滞，而非依赖侧不存在一种或两种模式，或者依赖侧感觉（恢复到L-2）和运动（恢复1级）阻滞的持续时间比非依赖侧长20%。60例患者中无一例出现单侧感觉阻滞。所有组中出现单侧运动阻滞的患者数量相当：T 0.5% + E组4例，T 1% + E组2例，T 0.5%组4例，T 1%组5例。同样，所有组中出现感觉和运动阻滞持续时间延长的患者数量相当：T 0.5% + E组分别为6例和8例，T 1% + E组分别为6例和9例，T 0.5%组分别为6例和8例，T 1%组分别为7例和7例。总之，尽管在所有四组患者中都注意到重比重丁卡因向依赖侧的优先分布，但与T 0.5% + E的标准溶液相比，使用更高浓度的丁卡因、省略肾上腺素或这两个因素的组合并没有导致更明显的差异性扩散。
