Modifiable, Postoperative Risk Factors for Delayed Discharge Following Total Knee Arthroplasty: The Influence of Hypotension and Opioid Use

• Authors: Albert T. Anastasio, Emory University; Kevin X. Farley, Emory University; Scott Boden, Emory University; Thomas Bradbury, Emory University; Ajay Premkumar, Emory University; Michael Gottschalk, Emory University
• Journal Title: JOURNAL OF ARTHROPLASTY
• Volume: Volume 35, Number 1
• Publisher: CHURCHILL LIVINGSTONE INC MEDICAL PUBLISHERS | 2020-01-01, Pages 82-88
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.arth.2019.07.047
• Subjects: Health Sciences, Medicine and Surgery; Engineering, Biomedical
• Keywords: Science & Technology; Life Sciences & Biomedicine; Orthopedics; total knee arthroplasty; opioid; hypotension; modifiable risk factors; length of stay; anemia; LENGTH-OF-STAY; TOTAL JOINT ARTHROPLASTY; TOTAL HIP-ARTHROPLASTY; TRANEXAMIC ACID; PREOPERATIVE PREDICTORS; REDUCES LENGTH; HOSPITAL STAY; REPLACEMENT; DEXAMETHASONE; OUTCOMES

Abstract

Background: We sought to identify independent modifiable risk factors for delayed discharge after total knee arthroplasty (TKA) that have been previously underrepresented in the literature, particularly postoperative opioid use, postoperative laboratory abnormalities, and the frequency of hypotensive events. Methods: Data from 1033 patients undergoing TKA for primary osteoarthritis of the knee between June 2012 and August 2014 at an academic orthopedic specialty hospital were reviewed. Patient demographics, comorbidities, inpatient opioid medication, postoperative hypotensive events, and abnormalities in laboratory values, all occurring on postoperative day 0 or 1, were collected. Multivariate logistic regression analysis was performed to identify independent risk factors for a prolonged length of stay (LOS) >3 days. Results: The average age of patients undergoing primary TKA in our cohort was 65.9 (standard deviation, 9.1) years, and 61.7% were women. The mean LOS for all patients was 2.64 days (standard deviation, 1.14; range, 1-9). And 15.3% of patients had a LOS >3 days. On multivariate logistic regression analysis, nonmodifiable risk factors associated with a prolonged LOS included nonwhite race (odds ratio [OR], 2.01), single marital status (OR, 1.53), and increasing age (OR, 1.47). Modifiable risk factors included every 5 postoperative hypotensive events (OR, 1.31), 10-mg increases in oral morphine equivalent consumption (OR, 1.04), and postoperative laboratory abnormalities (hypocalcemia: OR, 2.15; low hemoglobin: OR, 2.63). Conclusion: This study identifies potentially modifiable factors that are associated with increased LOS after TKA. Doubling down on efforts to control the narcotic use and to use opioid alternatives when possible will likely have efficacy in reducing LOS. Attempts should be made to correct laboratory abnormalities and to be cognizant of patient opioid use, age, and race when considering potential avenues to reduce LOS.