Incidence and Outcomes of Acute Kidney Injury After Orthotopic Cardiac Transplant: A Population-Based Cohort

Objectives: Acute kidney injury is a frequent complication after orthotopic cardiac transplant. We aimed to describe the risk factors for acute kidney injury after cardiac transplant according to Kidney Disease: Improving Global Outcomes criteria. Materials and Methods: We retrospectively studied a population-based cohort of cardiac transplant recipients (aged > 12 y) at Baskent University between February 2003 and January 2015. Of 94 patients, 64 were evaluated and included in the study. The main outcome was acute kidney injury, defined and classified according to Kidney Disease: Improving Global Outcomes criteria, during 7 postoperative days. Other outcomes included risk factors, use of renal replacement therapy, post operative complications, mortality, and kidney recovery. Results: Mean age at transplant was 34.14 +/- 16.30 years, and 45 patients (70.32%) were men. Acute kidney injury developed in 34 (53.12%) of 64 cardiac transplant recipients, with severity classified as stage 1 in 10 (15.62%), stage 2 in 14 (21.87%), and stage 3 in 10 (15.62%). Renal replacement therapy was given to 25 patients (39.06%). Patients with acute kidney injury were significantly older (40.41 +/- 15.85 y vs 27.03 +/- 13.91 y; P = .001), had larger body surface area (1.78 +/- 0.28 m(2) vs 1.61 +/- 0.31 m(2); P = .033), and more frequently had a history of hypertension (P = .011) and smoking (P = .007) than did patients without acute kidney injury. They also had lower intraoperative urine output (453.380 +/- 266.85 mL) than did patients who did not develop acute kidney injury (632.33 +/- 430.94 mL (P = .01). Conclusions: According to the Kidney Disease: Improving Global Outcomes criteria, acute kidney injury occurs in more than 50% of heart transplant patients postoperatively. Older age, larger body surface area, and history of hypertension and smoking are associated with acute kidney dys function following orthotopic heart transplant.