Table 2.
Baseline and operative characteristics by cohort and AKI. Data are expressed as the median (Q1–Q3) or number (percentage). ACE, angiotensin-converting enzyme; AKI, acute kidney injury; BMI, body mass index; CABG, coronary artery bypass graft; COPD, chronic obstructive pulmonary disease; LVEF, left ventricular ejection fraction; POD1, first postoperative day; Q1, Q3, first and third quartile, respectively; and SOFA, Sequential Organ Failure Score. The influence of baseline characteristics on AKI was analyzed by univariable logistic regression. Bold fonts indicate p-values < 0.05.
| Characteristic | Development Cohort | Validation Cohort | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| No AKI | AKI | p-Value | No AKI | AKI | p-Value | ||||||
| (n = 46) | (n = 14) | (n = 126) | (n = 22) | ||||||||
| Demographics | |||||||||||
| Age (years) | 67 | (59–75) | 69 | (68–78) | 0.047 | 67 | (59–75) | 69 | (68–78) | 0.171 | |
| Sex (female) | 11 | (24) | 4 | (29) | 0.678 | 33 | (26) | 6 | (27) | 0.869 | |
| BMI (kg/m2) | 27.4 | (25.0–29.9) | 26.5 | (23.8–33.2) | 0.767 | 27.1 | (24.8–30.3) | 28.5 | (22.9–30.4) | 0.876 | |
| Medication, No (%) | |||||||||||
| Beta blockers | 40 | (87) | 9 | (75) | 0.292 | 91 | (73) | 17 | (77) | 0.733 | |
| ACE Inhibitors | 35 | (76) | 8 | (67) | 0.478 | 69 | (55) | 12 | (55) | 0.943 | |
| Sartans | 6 | (13) | 1 | (8) | 0.840 | 27 | (22) | 7 | (32) | 0.271 | |
| Calcium channel blockers | 6 | (13) | 5 | (42) | 0.037 | 35 | (28) | 6 | (27) | 0.993 | |
| Diuretics | 36 | (78) | 11 | (92) | 0.456 | 52 | (42) | 13 | (59) | 0.138 | |
| Statins | 45 | (98) | 12 | (100) | 0.929 | 106 | (85) | 19 | (86) | 0.975 | |
| Acetylsalicylic acid | 44 | (96) | 12 | (100) | 0.860 | 103 | (82) | 18 | (82) | 0.848 | |
| Comorbidities, No (%) | |||||||||||
| Arterial hypertension | 28 | (61) | 11 | (85) | 0.159 | 89 | (71) | 18 | (82) | 0.362 | |
| Pulmonary hypertension | 3 | (7) | 1 | (8) | 0.741 | 6 | (5) | 2 | (9) | 0.328 | |
| Congestive heart disease | 7 | (15) | 4 | (29) | 0.255 | 16 | (13) | 0 | (0) | 0.201 | |
| LVEF < 35% | 10 | (22) | 2 | (14) | 0.651 | 6 | (5) | 2 | (9) | 0.328 | |
| Chronic kidney disease | 3 | (7) | 2 | (14) | 0.345 | 9 | (7) | 4 | (18) | 0.090 | |
| COPD | 3 | (7) | 2 | (14) | 0.345 | 15 | (12) | 3 | (14) | 0.707 | |
| Diabetes, insulin | 3 | (7) | 5 | (38) | 0.012 | 13 | (10) | 3 | (14) | 0.545 | |
| Previous cardiac surgery | 3 | (7) | 0 | (0) | 0.632 | 8 | (6) | 1 | (5) | 0.970 | |
| Serum creatinine at baseline (mg/dL) | 0.93 | (0.78–1.04) | 1.22 | (0.83–1.36) | 0.011 | 0.99 | (0.80–1.10) | 1.08 | (0.94–1.28) | 0.018 | |
| Type of Surgery | |||||||||||
| Isolated CABG | 24 | (52) | 3 | (21) | 0.064 | 78 | (62) | 11 | (50) | 0.274 | |
| Isolated valvular surgery | 8 | (17) | 4 | (29) | 0.344 | 16 | (13) | 4 | (18) | 0.425 | |
| Combined procedure | 14 | (30) | 7 | (50) | 0.191 | 30 | (24) | 7 | (32) | 0.403 | |
| other | 5 | (4) | 1 | (5) | |||||||
| Risk of AKI | |||||||||||
| Cleveland Clinic Foundation Score | 3 | (2–3) | 4 | (3–5) | 0.005 | 3 | (2–4) | 3 | (2–4) | 0.636 | |
| Duration of Surgery | |||||||||||
| Aortic cross clamp | 74.5 | (57.5–99) | 78.5 | (47–105) | 0.934 | 73 | (55–89) | 78 | (60–101) | 0.232 | |
| Cardiopulmonary bypass | 115 | (91–144) | 118.5 | (89.5–148.5) | 0.769 | 109 | (87–133) | 139 | (97–150) | 0.046 | |
| SOFA on POD 1 | 10 | (7.5–12) | 9 | (7–10) | 0.674 | 8 | (6–9) | 9 | (7–12) | 0.044 | |