Reduction of Opioid Use With Enhanced Recovery Program for Total Knee Arthroplasty
Background: Adequate pain control after total knee arthroplasty (TKA) is critically important to achieve early mobilization, shorten the length of hospital stay, and reduce postoperative complications. At Veterans Affairs North Texas Health Care System (VANTHCS) in Dallas, we implemented a multidisciplinary enhanced recovery after surgery (ERAS) protocol to deal with increasing length of stay and postoperative pain. We hypothesize that this protocol will reduce the overall opioid burden and decrease inpatient hospital length of stay in our TKA population.
Methods: A retrospective review of all TKAs performed by a single surgeon at VANTHCS from 2013 to 2018 was conducted. A postoperative ERAS protocol was implemented in 2016. We compared perioperative opioid use and LOS between cohorts before and after protocol implementation.
Results: Inpatient length of stay between cohorts was reduced from 66.8 hours for the standard of care (SOC) period to 22.3 hours in the ERAS cohort. Inpatient opioid use measured by total oral morphine equivalent doses averaged 169.5 mg and 66.7 mg for SOC and ERAS cohorts, respectively ( P = .0001). Intraoperative use of opioids decreased from 57.4 mg in the SOC cohort to 10.5 mg in the ERAS cohort ( P = .0001). Postanesthesia care unit (PACU) opioid use decreased from 13.6 mg (SOC) to 1.3 mg (ERAS) ( P = .0002). There was no significant difference in complications between cohorts ( P = .09).
Conclusions: Initiating a multidisciplinary ERAS protocol for TKA at VANTHCS significantly reduced inpatient length of stay and perioperative opioid use with no deleterious effects on complication rates. The ERAS protocol has major medical and financial implications for our unique VA population and the VA health care system.
Limitations
The limitations of this study include its retrospective study design. With the VHA patient population, it may be subject to selection bias, as the population is mostly older and predominantly male compared with that of the general population. This could potentially influence the efficacy of our protocol on a population of patients with more women. In a recent study by Perruccio and colleagues, sex was found to moderate the effects of comorbidities, low back pain, and depressive symptoms on postoperative pain in patients undergoing TKA.30
With regard to outpatient narcotic prescriptions, although we cannot fully know whether these filled prescriptions were used for pain control, it is a reasonable assumption that patients who are dealing with continued postoperative or chronic pain issues will fill these prescriptions or seek refills. It is important to note that the data on prescriptions and refills in the 3-month postoperative period include all narcotic prescriptions filled by any VHA prescriber and are not specifically limited to our orthopedic team. For outpatient narcotic use, we were not able to access accurate pill counts for any discharge prescriptions or subsequent refills that were given throughout the VA system. We were able to report on total prescriptions filled in the first 3 months following TKA.
We calculated total oral MEDs to better understand the amount of narcotics being distributed throughout our population of patients. We believe this provides important information about the overall narcotic burden in the veteran population. There was no significant difference between the SOC and ERAS groups regarding oral MED prescribed in the 3-month postoperative period; however, at the 6-month follow-up visit, only 16% of patients in the ERAS group were taking any type of narcotic vs 37.2% in the SOC group (P = .0002).
Conclusions
A multidisciplinary ERAS protocol implemented at VANTHCS was effective in reducing length of stay and opioid burden throughout all phases of surgical care in our patients undergoing primary TKA. Patient and nursing education seem to be critical components to the implementation of a successful multimodal pain protocol. Reducing the narcotic burden has valuable financial and medical benefits in this at-risk population.
