Table 2.
Surgery status, risk score, and clinical outcomes of the 2,162 patients according to the development of CSA-AKI based on KDIGO criteria.
| All patients n = 2,162 |
No CSA-AKI n = 1,233 |
CSA-AKI n = 929 |
P-value | |
|---|---|---|---|---|
| Surgery status, risk score, and clinical outcomes | ||||
| Previous cardiac surgery | 216 (10.0) | 92 (7.5) | 124 (13.3) | < 0.001 |
| Urgent/emergency surgery | 629 (29.1) | 340 (27.6) | 289 (31.1) | 0.073 |
| InsCor* | 2 (0 - 5) | 2 (0 - 4) | 3 (2 - 5) | < 0.001 |
| Low risk | 1290 (63.4) | 798 (68.3) | 492 (56.7) | < 0.001 |
| Intermediate risk | 576 (28.3) | 305 (26.1) | 271 (31.3) | 0.011 |
| High risk | 169 (8.3) | 65 (5.6) | 104 (12.0) | < 0.001 |
| Cardiopulmonary bypass duration (min) | 92 (76 - 111) | 90 (75 - 105) | 97 (79 - 120) | < 0.001 |
| < 90 | 916 (43.8) | 578 (48.0) | 338 (38.1) | < 0.001 |
| 90 to < 120 | 786 (37.6) | 460 (38.2) | 326 (36.8) | 0.498 |
| ≥ 120 | 389 (18.6) | 166 (13.8) | 223 (25.1) | < 0.001 |
| Type of surgery | ||||
| Coronary artery bypass grafting | 1230 (56.9) | 712 (57.7) | 518 (55.8) | 0.356 |
| Heart valve surgery | 1016 (47.0) | 559 (45.3) | 457 (49.2) | 0.075 |
| Multi-procedure open heart surgery | 201 (9.3) | 100 (8.1) | 101 (10.9) | 0.029 |
| Postoperative outcomes | ||||
| Renal replacement therapy up to 7 days | 40 (1.9) | 0 (0.0) | 40 (4.3) | < 0.001 |
| Reoperation for bleeding/tamponade | 76 (3.5) | 24 (1.9) | 52 (5.6) | < 0.001 |
| Acute atrial fibrillation | 232 (10.7) | 96 (7.8) | 136 (14.6) | < 0.001 |
| Tracheal reintubation up to 7 days | 136 (6.3) | 28 (2.3) | 108 (11.6) | < 0.001 |
| Prolonged pulmonary ventilation (> 24 hours) | 227 (10.5) | 42 (3.4) | 185 (19.9) | < 0.001 |
| Operating room extubation | 746 (34.5) | 490 (39.7) | 256 (27.6) | < 0.001 |
| Type 1 neurological injury† | 95 (4.4) | 33 (2.7) | 62 (6.7) | < 0.001 |
| Discharge and mortality | ||||
| ICU readmission | 122 (5.6) | 52 (4.2) | 70 (7.5) | 0.001 |
| ICU LoS up to 30 days | 3 (2 - 5) | 2 (2 - 4) | 4 (2 - 7) | < 0.001 |
| Long LoS (> 14 days) | 122 (5.6) | 26 (2.1) | 96 (10.3) | < 0.001 |
| Hospital mortality up to 30 days | 122 (5.6) | 25 (2.0) | 97 (10.4) | < 0.001 |
Values are presented as n (%) for categorical data or as medians with first and third quartiles for scalar values.
*InsCor is a Brazilian risk assessment model for patients undergoing coronary artery bypass grafting (CABG) and/or heart valve surgery (HVS) that uses 10 variables: age > 70 years; female sex; combined surgery (CABG and HVS); myocardial infarction < 90 days; reoperation; aortic valve replacement; tricuspid valve repair/replacement; serum creatinine > 2 mg/dL; left ventricular ejection fraction < 30%; and events (at least one of the following situations prior to surgery: intra-aortic balloon pump, cardiogenic shock, ventricular tachycardia or fibrillation, orotracheal intubation, acute renal failure, inotropic agents use, and cardiopulmonary resuscitation). The InsCor score ranges from 0 to 30 points and defines three categories of mortality risk after cardiac surgery: low risk (0 to 3 points), intermediate risk (4 to 7 points), and high risk (≥ 8 points).
†Type 1 neurological injury: new episode of motor deficit, coma, seizure, or encephalic lesion documented by cranial computed tomography or magnetic resonance imaging.
CSA-AKI=cardiac surgery-associated acute kidney injury; ICU=intensive care unit; KDIGO=Kidney Disease Improving Global Outcomes; LoS=length of stay