Despite the benefits of continuous peripheral nerve blocks, catheter dislodgment remains a major problem, especially in the ambulatory setting. A comparison of injection of local anesthetic through a catheter versus a needle for interscalene catheter placement has shown improved pain scores and reduced opioid requirements, suggesting that needle injection may be associated with secondary block failure. The earlier views stated that the injection of local anesthetic through the needle prior to the insertion of a catheter can lead to undiagnosed improper catheter placement, potentially resulting in a higher catheter failure rate compared to injection through the catheter only.
These results indicate that injection of local anesthetic via the catheter may provide better analgesia than injection through the needle prior to the insertion of a catheter. Source : Borg, L., Howard, S. K., Kim,…
