217 Effectiveness of transversus abdominis plane (TAP) blocks in ambulatory laparoscopic and robotic nephrectomies

Background and Aims Ultrasound-guided (USG) Transversus Abdominis Plane (TAP) blocks are fascial plane blocks widely used because of their technical ease and analgesic implications in abdominal surgery.1 However, only a few small-scale TAP studies in laparoscopic nephrectomies for tumor removal exist, none in an outpatient setting.2 We assessed the impact of TAP on pain, PONV and other clinical outcomes when included in an ERAS pathway for extended ambulatory nephrectomies. Methods We performed a retrospective chart review of 209 ambulatory surgery patients who underwent partial laparoscopic and robotic nephrectomies using an ERAS protocol from 09/2016–12/2019. Preoperative TAP blocks were performed bilaterally with 20 ml of 0.25% bupivacaine or ropivacaine, 50 mcg clonidine and 2 mg dexamethasone. We assessed the association between preoperative administration USG TAP (51%) vs. no block (49%) on postoperative outcomes: intraoperative fentanyl, postoperative opioid consumption using morphine milligram equivalent units (MME), PONV rate and hours to first ambulation. Results Our results demonstrated a trend toward decreased intraoperative MME requirements in the TAP group vs no TAP (p=0.061). Patients receiving a TAP also required less postoperative narcotic (p=0.043). After adjusting for Apfel Score, age and operative time, the need for PONV rescue medication although not significant trended 8.6% higher in those without a TAP (95% CI -2.7%, 19%; p=0.11). Conclusions We found evidence that US guided bilateral TAP blocks are associated with a reduced need for postoperative narcotics in ambulatory laparoscopic and robotic nephrectomies with a trend toward decreased intraoperative MME requirements. ERAS pathways should consider including TAP blocks, even for these minimally invasive surgeries.