Urine Output During Cardiopulmonary Bypass Predicts Acute Kidney Injury After Cardiac Surgery: A Single-Center Retrospective Analysis.
Urine output is closely associated with renal function and has been used as a diagnostic criterion for acute kidney injury (AKI). However, urine output during cardiopulmonary bypass (CPB) has never been identified as a predictor of postoperative AKI. Considering altered renal homeostasis during CPB, we made a comprehensible approach to CPB urine output and evaluated its predictability for AKI.Patients undergoing cardiovascular surgery with the use of CPB, between January 2009 and December 2011, were retrospectively reviewed. AKI was defined as an increase in serum creatinine ≥0.3 mg/dL in the first postoperative 48 hours. We extrapolated a possible optimal amount of urine output from the plot of probability of AKI development according to CPB urine output. After separating patients by the predicted optimal value, we performed stepwise logistic regression analyses to find potential predictors of AKI in both subgroups.A total of 696 patients were analyzed. The amount of CPB urine output had a biphasic association with the incidence of AKI using 4 mL/kg/h as a boundary value. In a multivariate logistic regression to find predictors for AKI in entire patients, CPB urine output did not show statistical significance. After separating patients into subgroups with CPB urine output below and over 4 mL/kg/h, it was identified as an independent predictor for AKI with the odds ratio of 0.43 (confidence interval 0.30-0.61) and 1.11 (confidence interval 1.02-1.20), respectively.The amount of urine output during CPB with careful analysis may serve as a simple and feasible method to predict the development of AKI after cardiac surgery at an early time point.
From the Department of Anesthesiology and Pain Medicine (YS, YLK, HMJ, JWJ, YCY); Anesthesia and Pain Research Institute (YS, YLK, YCY), Yonsei University College of Medicine, Seoul; Department of Policy Research Affairs (DWK), National Health Insurance Corporation Ilsan Hospital, Goyang; and Division of Nephrology (BSK), Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea.
Young
Y
Song
Dong Wook
DW
Kim
Young Lan
YL
Kwak
Beom Seok
BS
Kim
Hyung Min
HM
Joo
Jin Woo
JW
Ju
Young Chul
YC
Yoo
D058186:Acute Kidney Injury / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D006348:Cardiac Surgical Procedures / Q000009:adverse effects*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D012372:ROC Curve; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D014563:Urodynamics / Q000502:physiology*