Background: Although there are studies regarding immunosuppressed patients undergoing total knee arthroplasty (TKA) for inflammatory arthritis or osteonecrosis, there is a paucity of studies evaluating immunosuppressed patients undergoing TKA for diagnoses other than these.
Materials and methods: We identified all patients undergoing primary TKA for osteoarthritis from 2008-2014 in the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database. Overall, 111,624 patients were included. The immunosuppressed group consisted of 3,466 patients, and the control group included 108,158. Outcomes measured included operative time, lengths-of-stay, discharge destination, and 30-day complication rates. Univariate analysis was used to compare the outcomes. Multivariate regression analysis was then applied to determine if immunosuppression was an independent risk factor for differences in outcomes.
Results: Immunosuppressant use did not change operative time, lengths-of-stay, or discharge disposition. Immunosuppressed patients were at higher risks of developing the following surgical and medical complications: organ/space surgical site infection (SSI), wound dehiscence, deep venous thrombosis (DVT), pneumonia, urinary tract infection (UTI), and systemic sepsis. Return to the operating room and 30-day readmission were also significantly higher in the immunosuppressed group.
Conclusions: Patients taking chronic immunosuppressants and undergoing TKA for osteoarthritis are at higher risk of specific surgical and medical complications. These complications include organ/space SSI, wound dehiscence, DVT, pneumonia, UTI, and systemic sepsis. In addition, these patients were at increased odds of returning to the operating room and being readmitted.