Predictors of perioperative blood transfusions in patients with chronic kidney disease undergoing elective knee and hip arthroplasty.

BACKGROUND: Lower preoperative haemoglobin and older age pose a risk for perioperative allogeneic blood transfusions (ABT). The presence of chronic kidney disease (CKD) is associated with low haemoglobin, greater bleeding and ABT utilization. STUDY DESIGN AND METHODS: The interaction between estimated glomerular filtration rate (eGFR) and haemoglobin on perioperative ABT, length-of-stay and mortality was assessed in 86 patients with CKD stage 3 or higher undergoing elective total knee or hip arthroplasty compared with 294 without CKD. Multivariate analyses for ABT risk with haemoglobin, eGFR, age, gender, duration of surgery and primary versus revision surgery were performed. RESULTS: Patients with CKD had lower preoperative haemoglobin and higher incidence of ABT. Haemoglobin was independently associated with increased odds of ABT (0.74 (95% confidence interval 0.71-0.77), P = 0.001), but eGFR was not (0.98 (0.96-1.02), P = 0.089). Length-of-stay and 1 year mortality did not differ between non-transfused CKD patients and controls. Transfused CKD patients had significantly higher length-of-stay compared with transfused controls (25 ± 21 vs 19 ± 16 days, P < 0.0001), although 1 year mortality between transfused CKD patients and controls did not differ significantly. CONCLUSION: CKD alone, in the absence of anaemia, does not predispose to increased risk of ABT or length-of-stay in patients with mild-to-moderate CKD undergoing elective joint surgery. However, low haemoglobin is associated with increased ABT utilization and increased length-of-stay. Considering that 1 in 4 patients undergoing elective hip or knee arthroplasty has CKD, optimal preoperative patient blood management may improve outcome in this population.