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Background and Aims Effective postoperative pain control significantly impacts patient satisfaction and recovery. Continuous peripheral nerve blocks (CPNB) via catheter placement have been shown to reduce opioid requirements and facilitate early mobilization. Two primary techniques exist for catheter placement: conventional catheter-through-needle (CTN) method and catheter-over-needle (CON) approach. This review aims to explore advantages and disadvantages of both methods.Methods We performed a comprehensive literature search on studies evaluating catheter placement techniques for CPNBs. A total of 8 randomized controlled trials (RCT), 2 retrospective reviews, 1 ex-vivo study, and several case reports and descriptive articles were analyzed to assess outcomes related to catheter stability, leakage, and efficacy.Results Most common complications associated with CPNB include catheter dislodgement (6 to 15%) and leakage of local anesthetics at insertion site. In CTN technique, a smaller catheter is introduced through a larger-bore needle. After needle withdrawal, resulting tissue gap leads to anesthetic leakage and weaken catheter fixation, increasing risk of dislodgement (≈15%). Attempts to mitigate this issue using adhesive glues or tunneling have shown limited success. Moreover, leakage can compromise analgesia and increase infections. Leakage rates are reported as high as 34.4% in some studies. 1 RCT found that 27/29 patients (≈93%) experienced some degree of leakage. In contrast, the CON technique uses a larger catheter relative to puncture needle, ensuring a snug fit within tissue. Improved seal reduces leakage (6.1% as per 1 study) enhances catheter stability, thereby decreasing block failure and associated complications. As per literature, the overall procedure time was shorter when CON technique was used.Abstract EP147 Figure 1Catheter-over-needle assemblyAbstract EP147 Figure 2Catheter-through-needle assemblyAbstract EP147 Figure 3Comparison of CTN and CON techniquesConclusions Evidence from reviewed literature supports superiority of catheter-over-needle technique in continuous peripheral nerve blocks. By creating a more effective tissue seal, this method significantly reduces incidence of local anesthetic leakage and catheter dislodgement compared to traditional catheter-through-needle technique. Incorporating CON into clinical practice may improve patient outcomes and block reliability.