A. W. Knight1, E. B. Habermann1, D. S. Ubl1, M. D. Zielinski1, C. A. Thiels1 1Mayo Clinic,Trauma, Critical Care, And General Surgery,Rochester, MN, USA
Introduction: Open inguinal hernia repair (IHR) is thought to cause worse postoperative pain than minimally invasive surgery (MIS). Accordingly, these patients are often prescribed more opioids at discharge. We aimed to evaluate opioid use in patients undergoing IHR to optimize discharge prescribing practices for this common procedure.
Methods: Opioid-naïve adults undergoing open or MIS IHR were prospectively identified from three centers (3/17-11/17) to complete a 29-question telephone interview on median day 26 (IQR 23-30) following discharge. Opioid prescription and consumption data were converted into Morphine Milligram Equivalents (MMEs) and compared between MIS and open IHR. Univariate Chi-square, Fisher’s exact test, univariate, and multivariable logistic regression were used.
Results: Of 279 patients, 202 (72%) completed the survey and were included (n=100 open, n=102 MIS). Patients undergoing open IHR were slightly older (71 vs 65, p<0.001) and less likely to be female (5% vs 17%, p=0.008) than MIS patients. There was no difference in BMI (p>0.05). MIS IHR patients were more likely to have a bilateral IHR (open 5% vs MIS 48%, p<0.001). Discharge pain scores were similar (open 2.3±1.7 vs MIS 2.4±1.6; p=0.63).
Open IHR patients were more likely to receive opioids at discharge than those undergoing MIS IHR (98% vs. 90% MIS; p=0.03) and were prescribed slighter greater amounts of opioids (open 153 MMEs vs 150 MIS; p=0.049). There was no difference in opioid use by approach (open 15 MMEs vs 8 MIS; p=0.35). Most patients used less than 50 MMEs (open 72% vs MIS 75%; p=0.54). Over one-third of patients used no opioids (open 39% vs MIS 44%; p=0.50). 75% of prescribed opioids remained unused at time of survey. 11% of patients disposed of unused opioids. Mean days from surgery to cessation of opioid use was 2.6±3.9.
Most patients were satisfied with postoperative pain control (open 86% vs MIS 95%; p=0.09). However, the open group was more likely to report not being prescribed enough opioids at discharge (open 10%, MIS 1%; p=0.02). Bilateral repair was not associated with increased opioid use (univariate OR 1.23, p=0.56). On multivariable analysis, low discharge pain and normal BMI were independently associated with needing no opioids at discharge (Figure).
Conclusion: Post-discharge opioid utilization is similar between patients undergoing open and MIS IHR. Depending on patient factors, 0 to 8 tabs of 5 mg oxycodone is sufficient for most opioid-naïve patients undergoing IHR.
