TY - JOUR
T1 - The electrical properties of epidural catheters
T2 - What are the requirements for nerve stimulation guidance?
AU - Tamai, Hisayoshi
AU - Sawamura, Shigehito
AU - Atarashi, Hidenao
AU - Takeda, Kenji
AU - Ohe, Kazuhiko
AU - Hanaoka, Kazuo
PY - 2005/6
Y1 - 2005/6
N2 - We designed the present study to investigate the electrical resistance of commercially available epidural catheters and to search for products and procedures suitable for nerve stimulation-guided insertion. Four types: of epidural catheters were evaluated: 2 nonwirereinforced catheters (19-gauge and 20-gauge nylon) and 2 wire-reinforced catheters (19-gauge without stylet. and 20-gauge with stylet). The resistance of a catheter was calculated from the voltage level proportional to the fixed resistance in series circuit. In case of physiologic saline, the resistance of nonreinforced catheters was more than 700 kΩ, whereas the wire-reinforced catheter was 14.4 ± 0.20 kΩ without stylet and 10.1 ± 0.42 kΩ with stylet. When the stylet was passed through a 20-gauge nylon catheter, the resistance decreased to 49.2 ± 1.96 kΩ. When catheters were primed with 10% hypertonic saline, the resistance of both nonreinforced catheters decreased by one third compared with physiologic saline. The electrical resistance of the saline-filled epidural catheters significantly differed among products tested. We conclude that epidural catheterization that is guided by electrical stimulation should be performed only with catheters equipped with spiral stainless steel wire reinforcement or with a stainless steel stylet.
AB - We designed the present study to investigate the electrical resistance of commercially available epidural catheters and to search for products and procedures suitable for nerve stimulation-guided insertion. Four types: of epidural catheters were evaluated: 2 nonwirereinforced catheters (19-gauge and 20-gauge nylon) and 2 wire-reinforced catheters (19-gauge without stylet. and 20-gauge with stylet). The resistance of a catheter was calculated from the voltage level proportional to the fixed resistance in series circuit. In case of physiologic saline, the resistance of nonreinforced catheters was more than 700 kΩ, whereas the wire-reinforced catheter was 14.4 ± 0.20 kΩ without stylet and 10.1 ± 0.42 kΩ with stylet. When the stylet was passed through a 20-gauge nylon catheter, the resistance decreased to 49.2 ± 1.96 kΩ. When catheters were primed with 10% hypertonic saline, the resistance of both nonreinforced catheters decreased by one third compared with physiologic saline. The electrical resistance of the saline-filled epidural catheters significantly differed among products tested. We conclude that epidural catheterization that is guided by electrical stimulation should be performed only with catheters equipped with spiral stainless steel wire reinforcement or with a stainless steel stylet.
UR - https://www.scopus.com/pages/publications/19044371318
U2 - 10.1213/01.ANE.0000152641.01320.AC
DO - 10.1213/01.ANE.0000152641.01320.AC
M3 - 記事
C2 - 15920199
AN - SCOPUS:19044371318
SN - 0003-2999
VL - 100
SP - 1704
EP - 1707
JO - Anesthesia and Analgesia
JF - Anesthesia and Analgesia
IS - 6
ER -