MO341: Clinical Significance of Post-Operative Acute Kidney Disease After Non-Cardiac Surgery

Abstract

Abstract BACKGROUND AND AIMS Acute kidney disease (AKD), the condition of which acute kidney injury (AKI) has not recovered, is being emphasized because it increases the risk of progression to chronic kidney disease (CKD). Post-operative AKI (PO-AKI) is a common clinical setting prone to develop AKI although information on post-operative AKD (PO-AKD) is lacking. We investigated characteristics of PO-AKD events after non-cardiac surgery. METHOD We performed a retrospective cohort study from a tertiary referral center in South Korea. The patients who underwent non-cardiac surgery (five departments: general surgery, gynaecology, urology, neurosurgery and orthopedic surgery) >1 h from 2014 to 2020 were enrolled. Patients having advanced CKD patients and those receiving nephrectomy were excluded. PO-AKI was defined as whether the KDIGO AKI criteria were satisfied within 7 days after surgery. PO-AKD was defined as a case of not recovering to <1.5× from baseline within 7 days of peak creatinine measurement after surgery among PO-AKI patients. The information of death event and initiation of renal replacement therapy were collected. RESULTS A total of 83 361 patients were enrolled and 4824 (5.8%) cases of AKI and 852 cases of critical AKI (1.0%) were occurred. Among PO-AKI patients, 321 (6.7%) patients were progressed to PO-AKD. Patients with PO-AKD had a higher blood pressure, a lower body mass index, more coronary artery disease, higher inflammatory markers and a higher proportion of hematuria compared with those with PO-AKI but recovered. They were younger and more women. Moreover, they had fewer comorbidities such as lower SPARK scores, lower proportions of diabetes mellitus, hypertension and malignancy, and better kidney function immediately before receiving surgery than the recovered group (Table 1). However, they tended to experience more critical AKI (critical AKI event among PO-AKI 157 patients, 48.9%; recovery 695 patients, 15.4%) and consequently showed a higher incidence of all-cause mortality (post-operative 1 year: PO-AKD 56 patients, 17.4%; recovery 606 patients, 13.5%; p = .055; post-operative 3 year: PO-AKD 126 patients, 39.3%; recovery 1496 patients, 33.2%; p = .032) and newly started of renal replacement therapy after surgery (PO-AKD 49 patients, 15.3%; recovery 136 patients, 3.0%, p <.001). CONCLUSION In this large-scale study, we found that 6.7% of PO-AKI patients progressed to PO-AKD. PO-AKD patients tended to experience more severe AKI and also be associated with worse patients and kidney outcomes compared with their pre-existing condition.