Table 3.
Patients with or without acute kidney injury, n (%) unless stated otherwise
| No AKI n = 259 | Stage 1 AKI n = 6 | Stage 2 AKI n = 12 | Stage 3 AKI n = 16 | Univariate analysis P value | Multivariate analysis4P value | |
| Males | 122 (47) | 4 (67) | 7 (58) | 9 (56) | 0.61 | NS |
| Birth weight (g): mean (SD) | 1130 (267) | 976 (271) | 791 (257) | 850 (253) | < 0.0012 | NS |
| Gestational age (wk): median (range) | 29.0 (22-35) | 28.0 (23-32) | 25.0 (23-30) | 25.5 (23-38) | < 0.0013 | NS |
| Mode of delivery | 0.031 | NS | ||||
| Vaginal delivery | 40 (15) | 1 (17) | 3 (25) | 9 (56) | NS | |
| Cesarean section | 219 (84) | 5 (83) | 9 (75) | 7 (43) | NS | |
| Maternal steroids | 193 (74) | 5 (83) | 8 (67) | 11 (69) | 0.91 | NS |
| Intraventricular hemorrhage | < 0.0011 | NS | ||||
| Grade 1 | 15 (6) | 1 (16) | 0 (0) | 0 (0) | NS | |
| Grade 2 | 8 (3) | 1 (16) | 0 (0) | 1 (6) | NS | |
| Grade 3 | 9 (3) | 1 (16) | 1 (8) | 2 (13) | NS | |
| Grade 4 | 9 (4) | 0 (0) | 1 (8) | 6 (40) | NS | |
| Necrotizing enterocolitis | 16 (6) | 1 (16) | 6 (50) | 7 (43) | < 0.0011 | 0.001 |
| Patent ductus arteriosus | 0.031 | NS | ||||
| Tiny | 29 (11) | 1 (16) | 1 (8) | 3 (18) | NS | |
| Moderate | 32 (12) | 0 (0) | 3 (25) | 4 (25) | NS | |
| Large | 19 (7) | 1 (16) | 3 (25) | 2 (12) | NS | |
| Sepsis | < 0.0011 | NS | ||||
| Clinical sepsis | 45 (17) | 3 (50) | 6 (50) | 7 (43) | NS | |
| Sepsis with normotension | 22 (8) | 1 (16) | 0 (0) | 1 (6) | NS | |
| Sepsis with hypotension | 14 (5) | 1 (16) | 6 (50) | 5 (31) | NS | |
| Duration of mechanical ventilation (d): median (range) | 2 (1-160) | 3.5 (1-29) | 17.5 (7-71) | 13 (2-262) | < 0.0013 | NS |
| Surgery required | 11 (4) | 1 (16) | 4 (33) | 6 (37) | < 0.0011 | NS |
| Inotrope use | 37 (14) | 2 (33) | 8 (66) | 12 (75) | < 0.0011 | NS |
| Ibuprofen use | 51 (19) | 1 (16) | 7 (58) | 4 (25) | 0.011 | NS |
| Vancomycin use | 59 (22) | 3 (50) | 10 (83) | 12 (75) | < 0.0011 | NS |
| Gentamycin use | 173 (66) | 5 (83) | 11 (91) | 14 (87) | 0.081 | NS |
| Steroids use | 24 (9) | 1 (16) | 6 (50) | 7 (43) | < 0.0011 | NS |
| Umbilical arterial catheter use | 129 (49) | 5 (83) | 8 (66) | 16 (100) | < 0.0011 | NS |
| Oliguria | < 0.0011 | NS | ||||
| < 0.5 mL/kg per hour for 6 h | 0 (0) | 0 (0) | 1 (8) | 2 (12) | NS | |
| < 0.3 mL/kg per hour for 24 h | 0 (0) | 1 (16) | 3 (25) | 6 (37) | NS | |
| Hypotension | 35 (13) | 2 (33) | 9 (75) | 12 (75) | < 0.0011 | NS |
| Normal saline intravenous bolus | 28 (10) | 2 (33) | 9 (75) | 11 (68) | < 0.0011 | NS |
| Furosemide | 4 (1) | 1 (16) | 3 (25) | 4 (25) | < 0.0011 | NS |
| Duration of hospital stay in survivors (d): median (range) | 52 (15-280) | 64.5 (53-125) | 74.5 (7-116) | 116 (44-362) | 0.023 | NS |
| Mortality | 27 (10) | 2 (33) | 8 (66) | 9 (56) | < 0.0011 | NS |
| Serum creatinine (µmol/L) on discharge: median (range) | 44 (23) | 64 (56) | 93 (47) | 133 (135) | < 0.0013 | NS |
| Mean blood pressure (mmHg) on discharge: median (range) | 55 (13) | 48 (24) | 38 (13) | 41 (19) | < 0.0013 | NS |
1
χ2 or Fisher exact test;
2
Analysis of variance (ANOVA);
3
Kruskal-Wallis test;
4
Logistic regression. NS: Not significant; AKI: Acute kidney injury.