Abstract ID: A3

Abstract Title: Continuous Peripheral Nerve Block Catheter Tip Adhesion in a Rat Model

Authors: Buckenmaier C¹, Auton A², Flournoy S³
Walter Reed Army Medical Center Washington DC United States¹, Walter Reed Army Medical Center ², Walter Reed Army Institute of Research ³
Poster Type: Either

ABSTRACT BODY

Continuous peripheral nerve block (CPNB) has become an accepted technique for surgical anesthesia and postoperative analgesia. As such, it has been used effectively in combat casualties to provide extended duration analgesia during evacuation and convalescence. The technique is generally regarded as efficacious, however limited information exists concerning the tissue reaction coinciding with prolonged use of a CPNB catheter in situ. In this study, fourth-eight male, Sprague-Dawley rats were assigned (12 per group) to one of 4 catheter tip designs provided by Arrow International. Group A received a 20 gauge catheter with three side holes and a bullet shaped tip. Group B received a 19 gauge StimuCathTM catheter with a coiled omni-port end and hemispherical distal tip. Group C received a 19 gauge catheter with a single end hole in the conducting tip. Group D received a 19 gauge catheter with closed conducting tip and 4 side holes. Laparotomies were performed on all rats, followed by the creation of experimental injuries on the abdominal walls and cecums. A randomly assigned catheter tip was then sutured to the parietal peritoneal wall with the tip extending between the injuries. Catheter tips were removed from the adhesion mass after 7 days in situ with a force . Grams of force needed to remove each tip were recorded. Mean force (gm) ą standard deviation for Group A was 1.09 ą 1.21, Group B 21.20 ą 30.15, Group C 0.88 ą 1.47, and Group D 1.60 ą 2.50. Variation among each group mean force, as compared with Group B, was significant (p<0.05). There was no significant difference in adhesion force between groups A, C, and D. These data suggest that CPNB catheter tip design can have an impact on the interaction between the tip and underlying tissue in an inflammatory environment. This finding may have important clinical implications for CPNB catheters left in place for extended periods of time.

ATTACHED FILES

A3_Catheter Data graphed.doc

Reg Anesth Pain Med 2005; 30(3):A3