Table 1.
Baseline characteristics of the 826 patients included in the study according to quartiles of base deficit
| Variable | All patients n = 826 |
Base deficit quartiles | p value | |||
|---|---|---|---|---|---|---|
| [0–5] n = 207 |
[5–9] n = 206 |
[9–13] n = 207 |
> 13 n = 206 |
|||
| Demographics | ||||||
| Male gender | 564 (68.3) | 156 (75.4) | 148 (71.8) | 139 (67.1) | 121 (58.7) | < 0.001 |
| Age (year) | 61 [50, 73] | 60 [51, 71] | 64 [51, 77] | 60 [49, 72] | 62 [51, 74] | 0.678 |
| OHCA characteristics | ||||||
| Public setting | 262 (31.8) | 79 (38.3) | 71 (34.5) | 70 (33.8) | 42 (20.4) | < 0.001 |
| Witnessed CA | 698 (87.0) | 181 (90.5) | 183 (92.0) | 177 (88.5) | 157 (77.3) | < 0.001 |
| Bystander CPR | 444 (55.8) | 122 (62.2) | 122 (60.7) | 99 (49.5) | 101 (51.0) | 0.004 |
| Initial VF/VT | 414 (50.1) | 129 (62.3) | 121 (58.7) | 92 (44.4) | 72 (35.0) | < 0.001 |
| Collapse to ROSC, min | 20 [13, 30] | 16 [10, 25] | 20 [14, 27] | 22 [15, 33] | 29 [20, 40] | < 0.001 |
| Prehosp. infusion of bicar. | 113 (13.7) | 17 (8.2) | 22 (10.7) | 28 (13.5) | 46 (22.3) | < 0.001 |
| Chronic respiratory disease | 42 (5.1) | 11 (5.3) | 14 (6.8) | 8 (3.9) | 9 (4.4) | 0.399 |
| Chronic kidney disease | 45 (5.5) | 5 (2.4) | 12 (5.9) | 14 (6.9) | 14 (7.0) | 0.039 |
| Biological characteristics at ICU admission | ||||||
| pH | 7.22 [7.11, 7.31] | 7.33 [7.28, 7.39] | 7.27 [7.21, 7.32] | 7.18 [7.13, 7.25] | 7.03 [6.92, 7.11] | < 0.001 |
| PCO2 (mmHg) | 42.8 [36.0, 51.2] | 41.5 [36.8, 49.7] | 42.3 [36.3, 50.5] | 43.5 [35.7, 52.3] | 43.5 [35.1, 52.5] | 0.554 |
| Bicarbonate level (mmol/l) | 17.5 [14.0, 20.4] | 21.8 [20.7, 22.9] | 19.1 [17.8, 20.0] | 16.0 [15.0, 16.9] | 10.8 [8.7, 12.7] | < 0.001 |
| Urea level (mmol/l) | 7.3 [5.7, 10.2] | 6.8 [5.3, 8.9] | 7.3 [5.8, 9.8] | 7.5 [5.8, 10.6] | 8.1 [5.7, 13.2] | < 0.001 |
| Creatinine level (µmol/l) | 106 [78, 146] | 87 [69, 111] | 102 [77, 130] | 114 [86, 148] | 136 [101, 190] | < 0.001 |
| Phosphorus level (mmol/l) | 1.7 [1.1, 2.5] | 1.2 [0.9, 1.7] | 1.4 [1.0, 1.9] | 1.9 [1.3, 2.5] | 2.9 [2.1, 3.8] | < 0.001 |
| Lactate level (mmol/l) | 5.2 [2.5, 9.2] | 2.5 [1.6, 4.3] | 4.0 [2.3, 5.7] | 6.5 [3.5, 8.8] | 11.2 [7.6, 15.0] | < 0.001 |
| Base deficit (mEq/l) | 8.8 [5.3, 13.2] | 3.6 [2.8, 4.5] | 6.8 [6.0, 7.9] | 10.8 [9.7, 11.9] | 17.8 [15.2, 21.0] | < 0.001 |
| In-hospital characteristics | ||||||
| Cardiac cause-related CA | 436 (56.2) | 136 (68.7) | 122 (61.3) | 103 (54.5) | 75 (39.5) | < 0.001 |
| Post-resus. shock | 480 (58.1) | 87 (42.0) | 109 (52.9) | 119 (57.5) | 165 (80.1) | < 0.001 |
| Acute kidney injurya | < 0.001 | |||||
| No AKI | 243 (30.7) | 104 (51.5) | 71 (35.9) | 59 (30.3) | 9 (4.6) | |
| KDIGO 1 | 65 (8.2) | 12 (5.9) | 27 (13.6) | 19 (9.7) | 7 (3.6) | |
| KDIGO 2 | 45 (5.7) | 17 (8.4) | 13 (6.6) | 10 (5.1) | 5 (2.6) | |
| KDIGO 3 | 438 (55.4) | 69 (34.2) | 87 (43.9) | 107 (54.9) | 175 (89.7) | |
| Coronary angiography | 556 (67.3) | 145 (70.0) | 150 (72.8) | 135 (65.2) | 126 (61.2) | 0.019 |
| Therapeutic hypothermia | 717 (86.8) | 186 (89.9) | 182 (88.3) | 185 (89.4) | 164 (79.6) | 0.005 |
| RRT at day-1 | 335 (40.6) | 42 (20.4) | 56 (27.2) | 89 (43.0) | 148 (71.8) | < 0.001 |
OHCA out-of-hospital cardiac arrest, CPR cardiopulmonary resuscitation, ROSC restoration of spontaneous circulation, AKI acute kidney injury, KDIGO kidney disease improving global outcome, RRT renal replacement therapy
p value for trend has been calculated using a Chi-square trend test for binary variables and Cuzick test for ordinal and continuous variables
aMissing data are related to the missingness of basal level of creatinine in patients with chronic kidney disease