Abstract ID: A39
Abstract Title: Incidence of Complications Related to Epidural Catheterization in the Lower Thoracic Region
Poster Type: Either
ABSTRACT BODY
Introduction: Paramedian approach (PA) is considered a useful technique for epidural puncture at any level of the vertebral interspace. We reported that the incidence of transient paresthesia associated with epidural catheterization was highest in the lower thoracic region (1). We hypothesized that stiffness of epidural catheter might affect the incidence of paresthesia or other complications during epidural catheterization in the region. In this study, we compared the incidence of complications between polyamide (PLA; soft) catheter and polyethylene (PLE; stiff) catheter during epidural catheterization using PA.
Materials and Methods: After obtaining IRB approval and informed consent, adult patients were randomly divided into two groups according to the type of epidural catheter; i.e. Group A: 20G, closed-end PLA catheter (Perifix®, B. Braun, Inc., Melsungen, Germany) (n=223) and Group B: 18G, closed-end PLE catheter (Hakko, Tokyo, Japan) (n=214). The patient was positioned in a moderate chest-knee and right lateral decubitus position. Epidural puncture was performed at T11-12 interspace. The epidural space was identified by the loss-of-resistance technique with normal saline. The catheter was inserted to leave 5cm in the epidural space. Technical difficulties and the occurrence of major or minor complications were recorded. The cases of failed block or subarachinoid insertion of the catheter were also recorded. Data were analyzed with unpaired t-test or Chi-square analysis with Yate’s correction as appropriate. P < 0.05 was considered significant.
Results: Patients characteristics and number of attempts at needle insertion (Group A: 1.2 (0.5) and Group B: 1.2 (0.5) mean (SD)) were comparable between the groups ( P = 0.890). No signs suggesting major complications, including dural puncture and subarchnoid catheter placement, were recognized in all patients. Insufficient block was not recorded in each patient. Resistance to introduction of the catheter into the epidural space was significantly different between the groups (8.5% vs. 1.9%, P = 0.004). The incidence of blood aspiration from the catheter did not vary between the groups (1.8% vs. 4.2%, P = 0.168). Occurrence ratio of transient paresthesia during catheterization was comparable between the groups (6.8% vs. 8.0%, P = 0.760). There were no permanent neurologic complications in all cases.
Discussion: Because the lumbar enlargement of the spinal cord extends from the T9 to the upper border of L1 vertebrae, the shape of the epidural sac forms an oval or a hexagon, while it forms an inverted triangle in the lumbar region (2). This might influence the path and the ultimate position of the catheter, and the higher incidence of resistance during the catheter placement in the soft catheter group. This study indicates that PA should be the safe technique for epidural catheterization at lower-thoracic level regardless of the catheter stiffness.
References: 1) Ogura A. ASA meeting: 2000: A-891
2) Fukushige T. EJA: 1999: 16: 628-633
ATTACHED FILES
Reg Anesth Pain Med 2004; 29(2):A39