Comparison of Preoperative Versus Postoperative Transversus Abdominis Plane Block in Patients Undergoing Robotic-assisted Colorectal Surgery

Julia Xia, BA¹, Terrah J Paul Olson, MD¹, Yuan Liu, SPH¹, Shawn Tritt, MD², Seth A Rosen, MD¹. ¹Emory University School of Medicine, ²Emory Johns Creek Hospital

Introduction: Using transversus abdominis plane block (TAP) decreases pain scores and narcotic use post-operatively after colorectal surgery (CRS). It is unclear if TAP effectiveness varies if performed before versus after surgery.

Methods: All eligible patients undergoing CRS are offered TAP. In 2017, we transitioned from pre-operative to post-operative TAP to improve efficiency. Using a prospectively maintained database of robotic-assisted surgery, we compared 115 patients who underwent pre-operative TAP with 53 patients who underwent post-operative TAP. Primary endpoints were pain scores and morphine equivalent (ME) use post-operatively. Secondary endpoints included perioperative factors contributing to pain scores and post-operative ME use. Summary statistics and univariate analysis by non-parametric tests were utilized.

Results: From April 2015 through May 2018, 168 patients received TAP before or after CRS. The cohort included 79 (47.0%) women, average age 59.11 (±12.32) years, and mean body mass index (BMI) 28.32 (±5.82) kg/m². Surgery indication was cancer in 66 (39.3%), polyp in 43 (25.6%), and diverticulitis in 43 (25.6%) patients. Right colectomy was performed in 61 (36.3%), low anterior resection (LAR) in 46 (27.4%) and sigmoid colectomy in 40 (23.8%) patients. Demographics of the two groups were equivalent. Comparison of post-operative pain scores and ME use revealed no significant differences (See Table and Graph). Average pain scores and ME use were lower in patients who were older, underwent right colectomy, or had intracorporeal anastomosis.

Conclusions: In our cohort, no differences were seen in pain scores or ME use for patients receiving TAP pre-operatively versus post-operatively.