Abstract
Introduction
Opioid abuse is a national epidemic. Traditional pain management after total knee arthroplasty (TKA) relied heavily on opioids. The evidence that in-hospital multimodal pain management (MMPM) is more effective than opioid-only analgesia is overwhelming. There has been little focus on post-discharge pain management. The purpose of this study was to determine whether MMPM after TKA could reduce opioid consumption in the 30-day period after hospital discharge.
Methods
This was a prospective, two-arm, comparative study with a provider cross-over design. The first arm utilized a standard opioid-only (OO) prn regimen. The second arm utilized a 30-day MMPM regimen (standing doses of acetaminophen, metaxalone, meloxicam, gabapentin) and opioid medications prn. Surgeons crossed over protocols every four weeks. The primary outcome measure was VAS pain score. Secondary outcome measures included morphine milligram equivalents (MME) consumed, failure of the protocol, and manipulation under anesthesia (MUA). A pre-hoc power analysis was performed for the primary outcome measure and an intent-to-treat analysis was done utilizing a longitudinal mixed model.
Results
There were 43 patients in the OO cohort and 39 patients in the MMPM cohort. There was no difference in the baseline demographics or preoperative scores (p=0.94). There was no clinically meaningful difference in VAS score between the two groups at any time. The average opioid consumption at 30-days was 469 and 344 MME's for the OO and MMPM cohorts, respectively (p=0.026). 19/43 (44.2%) patients in the OO cohort failed vs. 4/39 (10.3%) in the MMPM cohort (p=0.002). There was 1 MUA in the OO and none in the MMPM cohort (p=0.338).
Discussion
A 30-day post-discharge multimodal pain regimen reduced opioid use after TKA. Opioid-only regimens are at an increased risk of failure to control pain. As a result of this study, multimodal pain management after hospital discharge is standard at our institution.