Table 1.

Clinical characteristics in patients with and without AKI progression

AKI Progressed
No (n=335)Yes (n=45)P Value
Demographics
 age, years72.3 (9.4)71.3 (9.9)0.39
 female93 (28%)13 (29%)0.87
 white race314 (94%)41 (91%)0.52
 patients with diabetes144 (43%)24 (53%)0.19
 congestive heart failure103 (31%)20 (44%)0.07
 ejection fraction, mean percent (SD)49.6 (13.7)50.5 (10.6)0.69
 preoperative creatinine, mg/dla1.14 (0.34)1.26 (0.45)0.12
 preoperative eGFR (CKD-EPI) ml/min64.3 (18.9)60.7 (22.7)0.22
  <3012 (3.6%)4 (8.9%)
  30–60126 (38%)17 (38%)
  60–90171 (51%)19 (42%)
  >9026 (7.8%)5 (11%)
 preoperative medications
  β-blockers251 (75%)34 (77%)0.78
  ACE inhibitors/ARB231 (69%)30 (67%)0.76
  aspirin245 (74%)36 (82%)0.24
  statins250 (75%)28 (64%)0.11
Preoperative biomarkers
 urine albumin to creatinine ratio (mg/g)23.2 (10.3, 73.8)29.6 (11.7, 69.5)0.66
 urine NGAL (ng/ml)10.1 (5.1, 21.6)9.8 (6.2, 17.4)0.78
 urine IL-18 (pg/ml)14.4 (6.9, 31.4)18.8 (9.2, 32.7)0.66
 plasma NGAL (ng/ml)64.3 (60.0, 106.1)67.9 (60.0, 125.1)0.51
Operative factors
 status of the procedure0.06
  elective246 (73%)27 (60%)
  urgent or emergent89 (27%)18 (40%)
Cardiac catheterization in the last 72 hours31 (9.4%)4 (8.9%)0.91
 surgery type0.17
  CABG158 (47%)17 (38%)
  valve94 (28%)11 (24%)
  CABG and valve83 (25%)17 (38%)
 IABP18 (5.4%)6 (13%)0.051
 repeat cardiac surgery77 (24%)8 (18%)0.38
 off CPB surgery22 (6.6%)4 (8.9%)0.57
 CPB time (min)b120.9 (58.1)165.2 (93.3)<0.001
 aortic cross-clamp time (min)b82.4 (44.6)112.5 (64.1)<0.001
  • Mean (SD), median (interquartile range), or number (percent). AKI progression defined by worsening of AKIN stage from original diagnosis of AKI. eGFR, estimated GFR; CKD-EPI, CKD epidemiology collaboration equation; ACE, angiotensin converting enzyme; ARB, angiotensin receptor blockers; CABG, coronary artery bypass grafting; IABP, intra-aortic balloon pump; CPB, cardiopulmonary bypass.

  • a To convert serum creatinine values (to µmol/L), multiply by 88.4.

  • b Perfusion time is reported for the patients who had CPB and cross-clamping.