Use of Echogenic Needles for Ultrasound-guided Transversus-Abdominis-Plane Block: Better Visibility Transforming into Better Postoperative Analgesia

Abstract

Introduction: Ultrasound (USG)-guided Transversus-Abdominis-Plane (TAP) block is recommended due to its safety and reliability. Echogenic needles provide better needle visibility and might result in better postoperative analgesia after USG-guided TAP block. Aim: To compare visibilty and block-characteristics (including postoperative analgesia) of echogenic vs. non echogenic needle for USG-guided TAP block. Materials and Methods: This randomised double-blind study was carried out at King George’s Medical University, Lucknow over a period of one year (November 2018 to October 2019). Seventy patients undergoing abdominal surgeries were enrolled and randomly allocated to one of two groups Group-E (echogenic) and Group-NE (non echogenic). Bilateral TAP block was performed postoperatively in all the patients and 20 mL of 0.25% Bupivacaine was deposited on each side. In Group-E, echogenic needle was used and in Group-NE, non echogenic needle was used for TAP block. Research assistant documented the start and finish time of the block procedure, number of attempts and redirections based on predetermined criteria. Visibility of needle tip and shaft were graded on a 3-point scale based on recorded and de-identified video-clips. Total procedure-time, number of needle redirections and skin punctures, incidence of vascular punctures, Visual Analogue Scale (VAS) scores and rescue analgesia requirement were also noted. Statistical analysis was done using SPSS Version 21.0. Results: Needle visibility on USG was significantly better in Group-E than Group-NE (χ2=57.24, p<0.001). Mean time to reach the TAP plane (t=-16.89, p<0.001) and total procedure time (t=-15.76, p<0.001) were also significantly lesser in Group-E. Mean number of needle redirections (t=-11.21, p<0.001), mean number of skin punctures (t=-2.12, p=0.038) and postoperative VAS scores throughout the study were found to be significantly lesser in group-E as compared to group-NE. Postoperative analgesia required in 24 hour was lesser in group-E and time of first rescue analgesia required was earlier in group-NE (p<0.001). Patients in both the groups were haemodynamically stable throughout the study. Conclusion: Use of echogenic needle for USG-guided TAP block provides much better needle-visibility resulting in better block-performance. It also provided better analgesia in our study as evident by lesser VAS-scores and lesser requirement of rescue analgesia postoperatively. So, use of echogenic needle should be advocated in all the patients undergoing USG-guided TAP blocks provided there are no financial constraints.