Continuous adductor canal block reduces opioid consumption, hospital length of stay, and non-home discharge disposition following total knee arthroplasty compared to epidural anesthesia

Abstract

Abstract Aims To compare the efficacy of a postoperative continuous adductor canal block (cACB) with and without a steroid adjuvant to that of epidural analgesia (EA). Methods All patients who underwent inpatient, primary total TKA at a single institution between July 2011 and November 2017 were included for retrospective cohort analysis. TKA patients were stratified into one of three analgesia approaches based on the time period of their date of surgery: EA, cACB without steroid adjuvant, and cACB with steroid adjuvant. Hospital length of stay (LOS), discharge disposition, incidence of postoperative adverse events, and total milligram morphine equivalents (MME) requirements were compared between analgesia approaches. Recursive feature elimination (RFE)-optimized multivariable logistic regression was performed to assess the independent effect of analgesia approach on prolonged LOS greater than 3 days (pLOS), non-home discharge, and total and daily MME requirements (tMME and dMME) following TKA. Results Of 4,345 patients undergoing TKA, 1,556 (35.83%) received EA, 2,087 (48.03%) received cACB without steroids, and 702 (16.13%) cACB with steroids. On univariate analysis, cACB patients experienced lower rates of pLOS (without steroids: 8.53%; with steroids: 8.40%; EA: 12.66%; p < 0.001), higher rates of discharge to home than EA patients (without steroids: 64.40%; with steroids: 75.07%; EA: 46.14%; p < 0.001), and lower tMME and dMME (without steroids: 318.8 tMME and 89.3 dMME; with steroids: 323.8 tMME and 103.0 dMME; EA: 625.0 tMME and 163.3 dMME; p < 0.001). On multivariable analysis, cACB groups were at a significantly lower odds of experiencing a pLOS compared to EA patients without steroids (OR = 0.64; 95% CI 0.49–0.84; p < 0.001; with steroids: OR = 0.54; 95% CI 0.38–0.76; p < 0.001). cACB groups had significantly lower odds of a non-home discharge when compared to EA patients (without steroids OR = 0.42; 95% CI 0.36–0.48; with steroids: OR 0.22; 95% CI 0.18–0.27). On multivariable analysis, cACB groups required significantly less tMME compared to the EA group (without steroids β=-290 MME; 95% CI: -313 to -268 MME; with steroids: β=-261 MME; 95% CI: -289 to -233 MME) as well as significantly lower dMME (without steroids: β=-66 MME/day; 95% CI -72 to -60 MME/day; p < 0.001; with steroids: β=-48 MME/day; 95% CI -55 to -40 MME/day; p < 0.001). Conclusion The current study is the first to simultaneously evaluate the efficacy of EA, cACB without perineural steroids, and cACB with steroids as local anesthetic adjuvants. These findings suggest cACB is significantly associated with greater discharge to home rates, lower rates of pLOS, and lower tMME and dMME consumption. Level of Evidence: Level III