Peripheral nerve blocks have been effective in decreasing post-operative pain as well as the use of narcotics for numerous years. Typically, these blocks are placed by anesthesiologist via ultrasound. In more recent years, surgeons have been placing nerve blocks laparoscopically. Since there are few studies that looks compare the two techniques we aim to perform a randomized control trial to demonstrate if a laparoscopic placed nerve block is as efficient and accurate as an ultrasound placed block.

Ultrasound-guided peripheral nerve blocks like the transversus abdominis plane (TAP) block are useful for post-operative pain control and reducing opioid analgesics.(1-3) A recent meta-analysis of TAP blocks in adults demonstrated a reduction in post-operative opioid requirements, and improved pain scores.(2) Within the pediatric population, numerous other studies have confirmed the benefit of TAP blocks and their ability to lower pain scores, reduce opioid use and opioid-related side effects post-operatively.(4) While there have been many prospective randomized trials for ultrasound-guided TAP blocks (5-7), there has been limited evaluation of surgically-placed TAP blocks (8). There has been no published data evaluating or comparing surgically placed TAP blocks in pediatric patients undergoing laparoscopic procedures. placed TAP blocks in pediatrics have not been examined in patients undergoing laparoscopic procedures.(4) Our pilot study was designed as a proof of concept, to demonstrate that ultrasound images could be used to verify the distribution of local anesthetic after a laparoscopically-assisted TAP block. The aim of this study is to continue using ultrasound to verify the location of laparoscopic-assisted TAP blocks, and compare the post-operative outcomes (pain scores, opioid use, etc.) to those who receive ultrasound-guided TAP blocks. We plan to do this in a prospective, randomized and semi-blinded fashion.

We hypothesize that (1) we will be able to accurately describe the location of the TAP block placed by both methods in more than 90% of cases; (2) laparoscopic-assisted TAP blocks will be as effective as ultrasound-guided TAP blocks in terms of managing/reducing post-operative pain scores and reducing the amount and frequency of postoperative opioid analgesia.

Inclusion Criteria:

• Patients age 0-18 years who are undergoing laparoscopic surgery at Lucille Packard Children's Hospital
• Clinical indication for abdominal peripheral nerve block

Exclusion Criteria:

• conversion to open procedure
• allergy to local anesthetic
• multiple procedures planned with >1 surgical specialty

Participants, their families, post-anesthesia care unit nurses and anesthesiologists reviewing images of the ultrasound will be blinded to the intervention.