Chunrong Wang1, Yuchen Gao1, Yu Tian1, Yuefu Wang2, Wei Zhao3, Daniel I Sessler4, Yuan Jia1, Bingyang Ji5, Xiaolin Diao6, Xinyi Xu6, Jianhui Wang1, Jun Li1, Sudena Wang1, Jia Liu1. 1. Department of Anaesthesiology, Fuwai Hospital, National Centre for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. 2. Department of Anaesthesiology and Surgical Critical Care Medicine, Beijing Shijitan Hospital, Capital Medical University, Beijing, China. Electronic address: wangyuefu3806@bjsjth.cn. 3. Information Centre, Fuwai Hospital, National Centre for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. Electronic address: zw@fuwai.com. 4. Department of Outcomes Research, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA. 5. Cardiopulmonary Bypass, Fuwai Hospital, National Centre for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China. 6. Information Centre, Fuwai Hospital, National Centre for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Abstract
BACKGROUND: Acute kidney injury (AKI) is common after cardiac surgery and is difficult to predict. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is highly predictive for perioperative cardiovascular complications and may also predict renal injury. We therefore tested the hypothesis that preoperative NT-proBNP concentration is associated with renal injury after major cardiac surgery. METHODS: We included 35 337 patients who had cardiac surgery and measurements of preoperative NT-proBNP and postoperative creatinine. The primary outcome was Kidney Disease: Improving Global Outcomes Stages 1-3 AKI. We also separately considered severe AKI, including Stage 2, Stage 3, and new-onset dialysis. RESULTS: Postoperative AKI occurred in 11 999 (34.0%) patients. Stage 2 AKI occurred in 1200 (3.4%) patients, Stage 3 AKI in 474 (1.3%) patients, and new-onset dialysis was required in 241 (0.7%) patients. The NT-proBNP concentrations (considered continuously or in quartiles) were significantly correlated with any-stage AKI and severe AKI (all adjusted P<0.01). Including NT-proBNP significantly improved AKI prediction (net reclassification improvement: 0.24 [0.22-0.27]; P<0.001) beyond basic models derived from other baseline factors in the overall population. Reclassification was especially improved for higher grades of renal injury: 0.30 (0.25-0.36) for Stage 2, 0.46 (0.37-0.55) for Stage 3, and 0.47 (0.35-0.60) for dialysis. CONCLUSIONS: Increased preoperative NT-proBNP concentrations were associated with postoperative AKI in patients having cardiac surgery. Including NT-proBNP substantially improves AKI predictions based on other preoperative factors.
BACKGROUND: Acute kidney injury (AKI) is common after cardiac surgery and is difficult to predict. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is highly predictive for perioperative cardiovascular complications and may also predict renal injury. We therefore tested the hypothesis that preoperative NT-proBNP concentration is associated with renal injury after major cardiac surgery. METHODS: We included 35 337 patients who had cardiac surgery and measurements of preoperative NT-proBNP and postoperative creatinine. The primary outcome was Kidney Disease: Improving Global Outcomes Stages 1-3 AKI. We also separately considered severe AKI, including Stage 2, Stage 3, and new-onset dialysis. RESULTS: Postoperative AKI occurred in 11 999 (34.0%) patients. Stage 2 AKI occurred in 1200 (3.4%) patients, Stage 3 AKI in 474 (1.3%) patients, and new-onset dialysis was required in 241 (0.7%) patients. The NT-proBNP concentrations (considered continuously or in quartiles) were significantly correlated with any-stage AKI and severe AKI (all adjusted P<0.01). Including NT-proBNP significantly improved AKI prediction (net reclassification improvement: 0.24 [0.22-0.27]; P<0.001) beyond basic models derived from other baseline factors in the overall population. Reclassification was especially improved for higher grades of renal injury: 0.30 (0.25-0.36) for Stage 2, 0.46 (0.37-0.55) for Stage 3, and 0.47 (0.35-0.60) for dialysis. CONCLUSIONS: Increased preoperative NT-proBNP concentrations were associated with postoperative AKI in patients having cardiac surgery. Including NT-proBNP substantially improves AKI predictions based on other preoperative factors.