Reduced post-operative opioid use decreases length of stay and readmission rates in patients undergoing hip and knee joint arthroplasty

Background: While adequate pain relief is central to patient recovery and satisfaction, opioid use is associated with side effects, adverse drug events and opioid use disorder and therefore is under increased scrutiny. Enhanced surgical recovery protocols include multimodal pain management as a key process, but the impact of opioid dose as an independent variable has not been examined.

Methods: Retrospective analysis of 51,824 hip and knee arthroplasty encounters in a large healthcare system.

Results: Overall, patients receiving treatment with lower doses of opiates had shorter median length of stay (p < 0.001); this earlier discharge had no negative consequences on readmission rates. In particular, patients discharged on day 1 received a lower median morphine milligram equivalent (MME) per day than those who were not discharged (32.5 [IQR: 19.0-50.0] versus 45.0 [26.7-71.2], respectively, p < 0.001). The probability of discharge on day 1 was 41.2% and 19.6% for those patients on lower versus higher MME/day, respectively. Similarly, there was a reduction in odds of readmission of 15.2% (95% CI 5.8-23.6%) for patients on lower doses of MME/day.

Conclusion: Lower MME/day following joint arthroplasty is linked to the probability of discharge on both days 1 and 2 post-surgery as well as reduced odds of readmission. These findings persisted even when adjusting for all other factors, including participation in the enhanced surgical recovery program, the use of a multi-modal analgesic regimen, the presence of complications, patient demographics, and other baseline characteristics. Efforts to reduce opioid use in the peri- and immediate post-operative period, regardless of the mechanism, demonstrated a significant effect on patient outcomes.