Reduced Opioid Prescription Practices and Duration of Stay after TAP Block for Laparoscopic Appendectomy

We evaluated whether TAP blocks performed at the time of appendectomy resulted in reduced total oral morphine equivalent (OME) prescribed and fewer 30-day opioid prescription (OP) refills.

Single institution review of historical data (2010-2016) was performed. Adults (≥ 18 years) that underwent appendectomy for appendicitis with uniform disease severity (AAST EGS grades I, II) were included. Opioid tolerance was defined as any preoperative OP ordered 1-3 months prior to appendectomy or < 1 month unrelated to appendicitis; opioid naïve patients were without OP. Intraoperative TAP blocks (admixture of liposomal/regular bupivacaine) were performed at surgeon discretion. Risk factors for discharge prescription > 200 OME were assessed using logistic regression and quantified using odds ratios (OR) and 95% confidence intervals (CI).

There were 960 patients with uniform appendicitis severity. During appendectomy, 145 (15%) patients received TAP blocks. There were 46 patients that were opioid tolerant (5%) and the majority of the cohort received discharge OP (n = 914, 95%) with a median prescription OME volume of 225 [150-300]. Only 76 patients required 30-day opioid prescription refill. On regression, factors associated with a discharge prescription > 200 OME included ≥ 65 years of age (OR 0.64 (95%CI 0.41-0.98)) and no TAP block (OR 1.7 (95%CI 1.2-2.5)) but not preoperative opioid utilization.

TAP blocks in low-grade appendicitis were associated with reduced OME prescribed, hospital duration of stay, and fewer refills without impacting operative time or total hospital costs.