Table 1 Clinical characteristics of the study population in the Non-AKI and AKI groups
Parameters | All (n = 1003) | Non-AKI(n = 675) | AKI(n = 328) | P |
|---|---|---|---|---|
General characteristics | ||||
 Age,y | 52.57 ± 13.35 | 50.46 ± 13.72 | 56.92 ± 11.41 |  < 0.001 |
 Gender (%):Male | 580 (57.8) | 376 (55.7) | 204 (62.2) | 0.051 |
 Female | 423 (42.2) | 299 ( 44.3) | 124 (37.8) |  |
 BMI,Kg/m2 | 22.99 ± 3.56 | 22.56 ± 3.36 | 23.87 ± 3.80 |  < 0.001 |
 ASA,grade(%) |  |  |  |  < 0.001 |
 2 | 21 (2.1) | 19 (2.8) | 2 (0.6) |  |
 3 | 778 (77.6) | 550 (81.5) | 228 (69.5) |  |
 4 | 201 (20.0) | 103 (15.3) | 98 (29.9) |  |
 5 | 3 (0.3) | 3 (0.4) | 0 (0.0) |  |
 Smoke (%) | 291 (29.0) | 184 (27.3) | 107 (32.6) | 0.079 |
 Drink (%) | 125 (12.5) | 78 (11.6) | 47 (14.3) | 0.212 |
Preoperative complications | ||||
 Stroke (%) | 62 (6.2) | 43 (6.4) | 19 (5.8) | 0.722 |
 Hypertension (%) | 265 (26.4) | 139 (20.6) | 126 (38.4) |  < 0.001 |
 Diabetes (%) | 99 (9.9) | 56 (7.3) | 43 (13.1) | 0.001 |
 Diabetes without treatment | 25 (2.5) | 17 (2.5) | 8 (2.4) | 0.940 |
 Diabetes treated with oral meditations | 54 (5.4) | 31 (4.6) | 23 (7.0) | 0.111 |
 Insulin-dependent diabetes | 20 (2.0) | 8 (1.2) | 12 (3.7) | 0.009 |
 Atrial fibrillation (%) | 196 (19.5) | 126 (18.7) | 70 (21.3) | 0.316 |
 Recent myocardial infarction (%) | 28 (2.8) | 18 (2.7) | 10 (3.0) | 0.730 |
 COPD (%) | 36 (3.6) | 25 (3.7) | 11 (3.4) | 0.780 |
 PH (%) | 340 (33.9) | 237 (35.1) | 103 (31.4) | 0.244 |
 Previous cardiac surgery (%) | 76 (7.6) | 36 (5.3) | 40 (12.2) |  < 0.001 |
 Cardiogenic shock (%) | 2 (0.2) | 1 (0.1) | 1 (0.3) | 0.602 |
 Intra-aortic balloon pump (%) | 2 (0.2) | 1 (0.1) | 1 (0.3) | 0.602 |
 NYHA III or IV (%) | 204 (20.3) | 106 (15.7) | 98 (29.9) |  < 0.001 |
Laboratory measurements | ||||
 LVEF,% | 64.21 ± 10.16 | 64.85 ± 9.74 | 62.90 ± 10.89 | 0.004 |
 WBC, × 109/L | 6.96 ± 2.19 | 6.82 ± 2.12 | 7.24 ± 2.31 | 0.004 |
 RBC, × 1012/L | 4.57 ± 0.70 | 4.62 ± 0.68 | 4.47 ± 0.72 | 0.001 |
 Hb,g/L | 131.93 ± 20.23 | 132.89 ± 19.36 | 129.97 ± 21.80 | 0.032 |
 HCT,% | 0.40 ± 0.06 | 0.40 ± 0.05 | 0.39 ± 0.06 | 0.015 |
 Plt, × 109/L | 220.67 ± 68.08 | 223.93 ± 65.25 | 213.95 ± 73.22 | 0.029 |
 ALT,U/L | 20 [14, 29] | 20 [13, 30] | 20 [15, 29] | 0.206 |
 AST,U/L | 23 [19, 29] | 22 [18, 29] | 23 [19, 30] | 0.063 |
 TBIL,umol/L | 13.8 [10.10, 19.25] | 13.9 [10.25, 19] | 13.8 [10, 20.33] | 0.633 |
 ALB,g/L | 38.78 ± 4.01 | 39.12 ± 3.96 | 38.08 ± 4.02 |  < 0.001 |
 BUN,μmol/L | 6.05 ± 2.28 | 5.86 ± 2.14 | 6.45 ± 2.48 |  < 0.001 |
 Scr,μmol/L | 79.33 ± 18.77 | 77.80 ± 18.22 | 82.48 ± 19.52 |  < 0.001 |
 eGFR | 80.88 ± 30.77 | 81.82 ± 25.40 | 78.96 ± 39.58 | 0.169 |
 UA,μmol/L | 399.28 ± 121.79 | 398.53 ± 118.22 | 400.83 ± 129.00 | 0.779 |
 INR | 1.05 [0.99, 1.14] | 1.05 [0.98, 1.13] | 1.06 [0.99, 1.19] | 0.138 |
 NT-proBNP,ng/L | 348.8 [104.25, 1126.50] | 280.3 [83.10, 1101.50] | 472.2 [151.65, 1186.25] |  < 0.001 |
Intra-operative characteristics | ||||
 Surgical time,min | 368.63 ± 126.52 | 337.23 ± 89.69 | 433.27 ± 161.98 |  < 0.001 |
 CPB time,min | 167.36 ± 82.53 | 147.59 ± 62.02 | 208.06 ± 102.34 |  < 0.001 |
 Aortic occlusion time,min | 95.98 ± 51.71 | 86.27 ± 44.98 | 115.96 ± 58.56 |  < 0.001 |
 Intra-operative defibrillation (%) | 239 (23.8) | 148 ( 21.9) | 91 (27.7) | 0.042 |
 Minimum temperature,℃ | 34.6 [34.10, 34.90] | 34.7 [34.20, 34.90] | 34.5 [34.00, 34.90] |  < 0.001 |
Intra-operative medications | ||||
 Dexmedetomidine (%) | 599 (59.7) | 390 ( 57.8) | 209 (63.7) | 0.072 |
 Dopamine (%) | 152 (15.2) | 109 ( 16.1) | 43 (13.1) | 0.208 |
 Dobutamine (%) | 624 (62.2) | 407 ( 60.3) | 217 (66.2) | 0.072 |
 Norepinephrine (%) | 845 (84.2) | 559 ( 82.8) | 286 (87.2) | 0.074 |
 Adrenaline (%) | 154 (15.4) | 68 ( 10.1) | 86 (26.2) |  < 0.001 |
Intra-operative inflow and outflow | ||||
 Blood loss,ml | 500 [400, 600] | 500 [400, 600] | 600 [400, 800] |  < 0.001 |
 Urine,ml | 1475.14 ± 854.58 | 1478.76 ± 815.34 | 1467.70 ± 931.42 | 0.848 |
 Crystalloid,ml | 1627.99 ± 558.99 | 1608.99 ± 528.86 | 1667.07 ± 615.40 | 0.123 |
 Voluven,ml | 0 [0.0, 0.0] | 0 [0.0, 0.0] | 0 [0.0, 0.0] | 0.511 |
 Gelofusine,ml | 0 [0.0, 500] | 0 [0.0, 500] | 0 [0.0, 500] | 0.003 |
 RBC transfusion,ml | 260 [0.0, 490] | 260 [0.0, 460] | 400 [0.0, 600] |  < 0.001 |
 FFP transfusion,ml | 400 [200, 600] | 400 [200, 450] | 400 [350, 600] |  < 0.001 |
 Cryoprecipitate transfusion,ml | 0 [0.0, 0.0] | 0 [0.0, 0.0] | 0 [0.0, 0.0] |  < 0.001 |
 ALB transfusion,ml | 0 [0.0, 0.0] | 0 [0.0, 0.0] | 0 [0.0, 0.0] | 0.169 |
 PLT transfusion,ml | 0 [0.0, 1.0] | 0 [0.0, 0.9] | 0 [0.0, 1.0] |  < 0.001 |
 Total infusion,ml | 5316.68 ± 2139.67 | 4961.12 ± 1822.05 | 6048.41 ± 2527.40 |  < 0.001 |
Surgery | ||||
 Valve surgery (%) | 611 (60.9) | 414 ( 61.3) | 197 (60.1) | 0.698 |
 CABG (%) | 127 (12.7) | 89 (13.2) | 38 (11.6) | 0.475 |
 Valve surgery combined with CABG (%) | 39 (3.9) | 20 (3.0) | 19 (5.8) | 0.030 |
 Vascular surgery (%) | 74 (7.4) | 25 (3.7) | 49 (14.9) |  < 0.001 |
 Congenital heart surgery (%) | 87 (8.7) | 75 (11.1) | 12 (3.7) |  < 0.001 |
 Heart transplant surgery (%) | 2 (0.2) | 0 (0.0) | 2 (0.6) | 0.042 |
 Other cardiac surgeries (%) | 63 (6.3) | 51 (7.6) | 12 (3.7) | 0.017 |
 Emergent surgery(%) | 14 (1.4) | 3 (0.4) | 11 (3.4) |  < 0.001 |
Indicator after surgery | ||||
 Postoperative PCT on day 1,ng/ml | 3.24 ± 8.48 | 1.83 ± 3.56 | 6.13 ± 13.48 |  < 0.001 |