Puolakka R, Pitkänen M T, Rosenberg P H
Department of Anaesthesiology, Helsinki University Central Hospital, Töölö Hospital, Topeliuksenkatu 5, FIN-00029 HYKS, Helsinki, Finland.
Reg Anesth Pain Med. 2000 Nov-Dec;25(6):584-90. doi: 10.1053/rapm.2000.16157.
Continuous spinal anesthesia (CSA) with microcatheters may be complicated because of technical problems. In elderly patients, some of the problems may be solved by using thicker catheters. A recent invention, involving a catheter-over-needle system, may prevent leakage of cerebrospinal fluid (CSF) and may also improve the prediction of the intrathecal position of the catheter tip.
This study included 90 patients undergoing primary hip or knee replacement, randomly allocated into 3 groups, with 30 patients in each group: Group EC, a 24-gauge epidural catheter through a 19-gauge Tuohy needle; group MC, a 28-gauge microcatheter through a 22-gauge spinal needle; group SC, a 22-gauge spinal catheter over a 27-gauge spinal needle through an epidurally placed 18-gauge Crawford needle. All subarachnoid catheterizations were performed with the patient in the lateral position and the initial spinal block dose was 2 mL of plain 0.5% bupivacaine. Increments of 0.5 mL were administered when required. The block performance characteristics were recorded, and the level of analgesia was studied in a blinded fashion. Catheter function during the postoperative infusion was assessed. Afterwards the needles and catheters were examined by microscopy.
The frequency of the successful catheterization was higher in the EC and MC groups (90% in each) than in the SC group (63%) (P <.05). The mean duration of the successful catheterizations, as well as the median level of analgesia, were similar in the groups. The postoperative infusion had to be stopped in 3, 1, and 1 patients in groups EC, MC, and SC, respectively, because of a technical reason. No neurologic sequelae occurred in this study. Microscopy showed 4 distorted spinal needle tips (2 each with MC and SC) and minor material damage of the SC catheters when bone had been met during block performance.
Placement of the SC catheters was unsuccessful to a high degree, and bone contact produced distortion of the tip of some of these catheters. Otherwise, the quality associated with catheterization time, anesthetic distribution, and catheter function was similar with the 3 catheters.
使用微导管进行连续脊麻（CSA）可能会因技术问题而出现并发症。在老年患者中，一些问题或许可通过使用更粗的导管来解决。一项涉及针内导管系统的最新发明，可能会防止脑脊液（CSF）渗漏，还可能改善对导管尖端鞘内位置的预测。
本研究纳入了90例行初次髋关节或膝关节置换术的患者，随机分为3组，每组30例：EC组，通过19号Tuohy针置入24号硬膜外导管；MC组，通过22号脊麻针置入28号微导管；SC组，通过硬膜外置入的18号Crawford针，在27号脊麻针外套入22号脊麻导管。所有蛛网膜下腔置管均在患者侧卧位时进行，初始脊麻阻滞剂量为2 mL普通0.5%布比卡因。必要时追加0.5 mL。记录阻滞操作特征，并以盲法研究镇痛水平。评估术后输注期间的导管功能。之后通过显微镜检查针和导管。
EC组和MC组的置管成功率较高（每组均为90%），高于SC组（63%）（P<.05）。各组成功置管的平均持续时间以及镇痛中位水平相似。由于技术原因，EC组、MC组和SC组分别有3例、1例和1例患者术后输注不得不停止。本研究未发生神经后遗症。显微镜检查显示，在阻滞操作过程中遇到骨质时，有4个脊麻针尖端变形（MC组和SC组各2个），SC组导管有轻微材料损伤。
SC组导管的置入成功率较低，与骨质接触导致部分导管尖端变形。除此之外，这3种导管在置管时间、麻醉分布和导管功能相关质量方面相似。
