Less leakage and dislodgement with a catheter-over-needle versus a catheter-through-needle approach for peripheral nerve block: an ex vivo study

Abstract

Less leakage and dislodgement with a catheter-over-needle versus a catheter-through-needle approach for peripheral nerve block: an ex vivo study Moins de fuites et de déplacements avec un cathéter par-dessus l'aiguille qu'avec un cathéter à travers l'aiguille pour un bloc nerveux périphérique: une étude ex vivo Abstract Purpose The objective of this study was to compare the catheter-through-needle (CTN) and catheter-over-needle (CON) catheterization techniques ex vivo by measuring leak pressure around the catheter and the catheter's resistance to pulling force. Methods Using an ex vivo porcine limb model, we compared the conventional CTN design with the CON design with respect to the ability to resist leakage at the catheter insertion site under high injection pressure and the force required to withdraw the catheter from tissue. One CON assembly (MultiSet, Pajunk) and three CTN assemblies (Contiplex, B.Braun; StimuCath, Arrow; Stimulong Sono, Pajunk) were studied. Ten porcine hind limbs were used to test leakage and another ten were used to measure withdrawal force. Catheters were placed at angles of 15°and 30°at depths of 3 cm and 5 cm. Leakage was assessed visually at the insertion site, and pressure was measured at the moment leakage occurred. Withdrawal force was measured by pulling the catheter from the tissue. Results No evidence of leakage was detected at the CON catheter insertion site at the highest pressure applied (1,000 mmHg) (n = 40). The CON assembly withstood significantly higher injection pressure than the CTN catheters without causing leaks at the catheter insertion site [CON, mean (standard deviation) [ 1,000 (0)

Lower interscalene approach for elbow surgery

“…The catheter was removed without any evidence of kinking, and the dressing remained dry and intact throughout. 5 Our clinical observations show that use of the low interscalene approach is successful at providing analgesia for elbow and distal humerus surgery, and it has the additional advantage of being able to secure the catheter without the risk of dislodgement. We have used this approach to introduce ten lower interscalene catheters in the last two months, and all have been successful.…”

The catheter-over-needle assembly facilitates delivery of a second local anesthetic bolus to prolong supraclavicular brachial plexus block without time-consuming catheterization steps: a randomized controlled study

“…On the other hand, the catheter-overneedle design features a catheter with a larger diameter than that of the needle, creating a ''tight fit'' between the catheter and the skin that helps prevent leakage or dislodgement without the need for tunnelling or applying glue. 9 In this study, catheter stability was further increased by adopting a medial-to-lateral approach. As shown previously, 17 this technique may provide a more anatomic approach to catheter threading along the brachial plexus, as the catheters usually pass easily without complications.…”

“…Potentially, this could be facilitated by placement of a catheter-over-needle assembly, which eliminates the need for multiple cumbersome catheterization steps and has a simple insertion method comparable with that of the single-shot technique. 8,9 The aim of this randomized study was to evaluate the effectiveness of delivering a second bolus of local anesthetic via a catheter-over-needle perineural catheter to prolong a supraclavicular block. A secondary aim was to assess the feasibility and ease of using a catheter-over-needle assembly to facilitate delivery of the postoperative bolus without prolonging the time required to perform the block.…”

The catheter-over-needle assembly offers greater stability and less leakage compared with the traditional counterpart in continuous interscalene nerve blocks: a randomized patient-blinded study

“…Indeed, our prior experience with CON catheter assemblies shows their stability and effectiveness at mitigating the problems of leakage and dislodgement. 5 Unfortunately, the problem of leakage led to a premature termination of the study, leaving us with a relatively small sample size. Although this renders us unable to perform an adequate statistical analysis comparing the two catheterization methods, it is perhaps more significant that, in light of the observable superiority of the CON assembly in preventing leakage, our institution's orthopedic surgeons have requested that all future continuous interscalene blocks be performed with CON catheters.…”