A Clinical Score to Predict Acute Kidney Injury After Heart Valve Replacement Surgery
A Clinical Score to Predict Acute Kidney Injury After Heart Valve Replacement Surgery
Acute kidney injury (AKI) is a common and severe complication of cardiac surgery. The main
 stay treatment remains preventive with no clear evidence supporting any therapeutic
 interventions. AKI risk prediction scores are an objective, transparent means of cohort
 enrichment but are not widely used. The purpose of this analysis was to develop and validate
 a clinical score including pre-,intra-and post-operative predictors that predicted AKI
 following heart valve replacement surgery. This prediction score allows identification of
 patients at high risk of AKI and may support decision-making for protective kidney treatment.
This study is a single center retrospective observational study designed to to develop and
 validate a clinical score that predicts AKI after heart valve replacement surgery。 To achieve
 this goal, patient underwent heart valve replacement surgery will be screened for enrollment
 eligibility. For the purpose of this analysis, only the first surgical episode was
 considered. Patients required preoperative dialysis, with any degree of renal insufficiency
 (acute or chronic) and patients who had end-stage renal disease (estimated glomerular
 fltration rate [eGFR] < 15 mL/min /1.73m2 )are not included in study.

 AKI was classified according to the KDIGO definition[10]. Stage-1 AKI: increase in serum
 creatinine of more than or equal to 0.3 mg/dl (≥ 26.5μmol/l) or increase to more than or
 equal to 150% to 200% (1.5≤x<2) from baseline within 7 days. Stage-2 AKI: Increase in serum
 creatinine to more than 200% to 300% (2≤x<3) from baseline. Stage-3 AKI: Increase in serum
 creatinine to more than 300% (3≤) from baseline (or serum creatinine of more than or equal to
 4.0 mg/dl (≥ 353.6μmol/l) or when the patient commenced RRT.

 We selected demographic, preoperative, intra-operative and early postoperative variables
 considered predictors of AKI.

 1. The demographic and preoperative factors included age, sex, weight, height; history of
 smoke, drink, angina, cerebrovascular disease, COPD, peripheral vascular disease,
 hypertension, valve infection , arrythmia , diabetes mellitus, MI , atrial fibrillation,
 pulmonary hypertension, previous cardiac surgery; NYHA stage, surgery type , Operative
 approach and emergency surgery。The latest value before operation: serum creatinine
 level, haemoglobin, capillary glucose, hemoglobin，WBC, EF, LDL-C , urinary protein, CRP,
 PCT, ALB, TBIL, PT and Glomerular filtration rate (GFR). History of taking the following
 drugs before surgery: contrast, nephrotoxic antibiotics, β-blocker, calcium channel
 blocker, lasix, ACEI, ARB, immunosuppressive, heparin, aspirin, clopidogrel, ticagrelor,
 digoxin, levosimendan, dopamine, dobutamine, cedilanid, isosorbide dinitrate, isosorbide
 mononitrate, isoprenaline and NASID.

 2. The intra-operative factors included cardiopulmonary bypass time, cross-clamp time,
 transfusion, FFP, VFP, CFP，output and input ; the highest blood glucose, minimum
 hematocrit, minimum mean arterial pressure, minimum temperature and fluid balance during
 CPB.

 3. The postoperative factors included time to extubation, mean ICU and hospital stay and
 mortality. First measured value after entering ICU: CVP, PH, HB.

 We also considered postoperative complications during the intensive care unit included IABP,
 ECMO, cardiac arrest, arrhythmia, re-intubation, return to ICU，tracheotomy.
Inclusion Criteria:

 -  > 18 years

 -  Subjects undergoing heart valve replacement surgery

 Exclusion Criteria:

 -  Pregnancy

 -  Transplant donor or recipient

 -  Required preoperative dialysis, with any degree of renal insufficiency (acute or
 chronic) and patients who had end-stage renal disease (estimated glomerular fltration
 rate [eGFR] < 15 mL/min /1.73m2 )

 -  Local anesthesia

 -  Lack of creatinine