Standardized Multimodal Pain Management Reduces Post-Operative Pain and Length of Stay in Hospital for Total Knee Arthroplasty: A Retrospective Review

Study Objective: To evaluate the utility of multimodal pain management subsequent to general or neuraxial anesthesia following total knee arthroplasty. Design: Retrospective review. Setting: University-affiliated teaching hospital. Patients: 389 patients (ASA physical status I-IV) scheduled for elective total knee replacement surgery over 3 year period. Interventions and Measurements: A total of 218 patients met inclusion criteria: 1) status-post a total knee arthroplasty 2) femoral nerve block with a continuous infusion of 0.1% ropivacaine 3) femoral catheter discontinued on post-op day 3, and 4.) follow-up with acute pain service. The study group (S) (N=105) received multimodal pain management consisting of a continuous femoral nerve blockade, celecoxib 200mg PO Q24 hrs, oxycontin 10mg PO Q12, acetaminophen 1000mg PO TID, and Percocet 5/325 1-2 tabs PO Q4-6 hr PRN (≤3 tabs/24hrs). The control group (NS) (N=113) received a continuous femoral nerve block with a non-standardized pain management regimen as prescribed by the orthopedic service. Outcome measurements included: mode of anesthesia (neuraxial vs. GA); length of surgery; time to ambulation and 90 flexion; pain score, morphine equivalents and length of stay in hospital. Main Results: The study group demonstrated decreased pain scores on the third post-operative day as compared to the control group (S=2.43 vs. NS=3.38, p=0.003, SEM + 0.215). The study group also demonstrated reduced length of stay relative to controls (S=3.64 vs. NS=4.47, p<0.001, SEM + 0.114). Conclusion: Multimodal pain management following total knee arthroplasty improved postoperative outcomes irrespective of opioids requirements or mode of anesthesia. Our results are consistent with previous work demonstrating improved patient care, superior analgesia and reduced length of stay in hospital through implementation of standardized multimodal pain management with standardized discharge criteria.