The influence of chronic kidney disease on the duration of hospitalisation and transfusion rate after elective hip and knee arthroplasty.

Abstract

Elective hip or knee replacement is an optimal, standardised orthopaedic surgical procedure. The influence of chronic kidney disease, defined as an estimated glomerular filtration rate (eGFR) of 15-45ml/min/1.73m2 body surface area (BSA) (KDIGO stage G3a-G4), on the duration of hospitalisation, perioperative decrease in haemoglobin (Hb) levels, and transfusion rates after orthopaedic procedures has not been fully clarified. Our study, therefore, aimed to evaluate the impact of chronic kidney disease on the previously mentioned variables. We conducted a retrospective multicentre analysis involving two orthopaedic centres. Patients who underwent elective total hip and knee replacement between 2010 and 2015 were included. We used descriptive methods and multivariate linear and binary regression analyses for our statistical evaluations. We evaluated 3301 datasets (1120 men [33.9%], 2181 women [66.1%], 2043 [61.9%], and 1258 [38.1%]) elective total hip and knee replacements, respectively. The following variables were identified as risk factors for a prolonged hospital stay: patient age, admission Hb and potassium levels, perioperative Hb level decrease, year of surgery, blood transfusion, and a preoperative eGFR of 15-45ml/min/m2 BSA. Patients with an eGFR of > 45ml/min/m2 BSA were discharged within 11.7 ± 3.0days, while patients with an eGFR of 15-45ml/min/1.73m2 BSA remained inpatient for 13.5 ± 5.0days (p < 0.001). Identified risk factors for postoperative blood transfusions included age, initial Hb level, perioperative Hb decrease, prosthetic hip replacement, and the presence of allergic diathesis. Blood transfusions were performed in 7.5% of patients with an eGFR of > 45ml/min/m2 BSA compared to 24.1% of patients with an eGFR of 15-45ml/min/1.73m2 BSA (p < 0.001). An eGFR level of 15-45ml/min/m2 BSA was identified as a risk factor for a postoperative decrease in Hb levels. Chronic kidney disease, defined as an eGFR level of 15-45ml/min/1.73m2 BSA, was a risk factor for a prolonged hospital stay after elective hip and knee arthroplasty. Further studies are necessary to better define the effect of reduced kidney function on relevant clinical and socioeconomic outcome parameters.