Table 1.
Characteristics, Management, and Outcomes by Baseline Biomarker Concentration
| Variable | Aldosterone |
P Value | BNP |
P Value | ||
|---|---|---|---|---|---|---|
| Above Median (n = 316) |
Below Median (n = 316) |
Above Median (n = 313) |
Below Median (n = 313) |
|||
| Baseline characteristic | ||||||
| Age, y | 48.2 ± 15.7 | 50.8 ± 15.6 | .03 | 52.3 ± 16.4 | 46.6 ± 14.5 | < .001 |
| Men, No. (%) | 160 (51) | 165 (52) | .69 | 149 (48) | 173 (55) | .06 |
| White, No. (%) | 221 (70) | 203 (64) | .30 | 213 (68) | 208 (66) | .48 |
| BMI, kg/m2 | 30.0 ± 8.0 | 27.9 ± 7.3 | < .001 | 28.0 ± 7.1 | 30.0 ± 8.3 | .004 |
| Primary lung injury, No. (%) | .18 | < .001 | ||||
| Pneumonia | 139 (44) | 160 (51) | 157 (50) | 139 (44) | ||
| Sepsis | 72 (23) | 74 (23) | 85 (27) | 59 (19) | ||
| Aspiration | 51 (16) | 43 (14) | 41 (13) | 51 (16) | ||
| Other | 44 (14) | 26 (8) | 33 (10) | 67 (21) | ||
| Coexisting conditions, No. (%) | ||||||
| Diabetes | 53 (17) | 59 (19) | .51 | 55 (18) | 55 (18) | .97 |
| HIV infection or AIDS | 15 (5) | 19 (6) | .47 | 17 (6) | 17 (6) | .98 |
| Malignancy | 13 (4) | 20 (6) | .14 | 13 (4) | 19 (6) | .35 |
| APACHE III on enrollment | 95.4 ± 31.7 | 91.1 ± 28.3 | .12 | 95.9 ± 30.7 | 90.6 ± 29.5 | .03 |
| Hemodynamic variables | ||||||
| Mean arterial pressure, mm Hg | 76.7 ± 14.7 | 79.3 ± 15.1 | .048 | 77.9 ± 15.1 | 78.3 ± 14.8 | .44 |
| Vasopressor, No. (%) | 115 (36) | 86 (27) | .01 | 114 (36) | 85 (27) | .01 |
| CVP, mm Hg | 12.8 ± 4.7 | 11.2 ± 4.5 | < .001 | 12.0 ± 4.8 | 12.1 ± 4.6 | .66 |
| PAOP, mm Hg | 15.9 ± 4.6 | 16.0 ± 5.5 | .85 | 15.9 ± 5.1 | 16.0 ± 5.0 | .89 |
| Cardiac index, L/min/m2 | 4.3 ± 1.4 | 4.4 ± 1.6 | .94 | 4.2 ± 1.5 | 4.6 ± 1.5 | .03 |
| Preenrollment fluid balance, L | 2.8 ± 3.6 | 2.6 ± 3.6 | .58 | 2.8 ± 3.4 | 2.6 ± 3.8 | .18 |
| Respiratory variables | ||||||
| Tidal volume, mL/kg of PBW | 7.4 ± 1.6 | 7.5 ± 1.8 | .82 | 7.0 ± 1.7 | 7.5 ± 1.7 | .23 |
| PaO2:FIO2 | 143.7 ± 64.0 | 152.2 ± 70.5 | .20 | 144.6 ± 61.9 | 150.9 ± 71.4 | .53 |
| Laboratory variables | ||||||
| Creatinine, mg/dL | 1.3 ± 1.0 | 1.1 ± 0.7 | < .001 | 1.4 ± 1.0 | 1.2 ± 0.7 | .11 |
| Hemoglobin, g/dL | 10.7 ± 2.0 | 10.2 ± 1.8 | .003 | 10.3 ± 1.8 | 10.5 ± 2.0 | .40 |
| Time since ICU admission, h | 40.2 ± 63.2 | 36.3 ± 31.4 | .74 | 36.7 ± 60.6 | 39.9 ± 36.4 | .42 |
| On-study management | ||||||
| Conservative study group | 167 (53) | 154 (49) | .30 | 167 (53) | 150 (48) | .17 |
| Cumulative fluid balance, L | 3.5 ± 10.1 | 4.2 ± 10.5 | .56 | 4.1 ± 11.1 | 3.6 ± 9.6 | .89 |
| Total furosemide dose, mg | 311 ± 486 | 300 ± 448 | .73 | 280 ± 411 | 333 ± 519 | .29 |
| Clinical outcomes | ||||||
| Death by 60 d, No. (%) | 62 (20) | 77 (24) | .15 | 77 (25) | 59 (19) | .08 |
| Ventilator-free days | 14.4 ± 10.1 | 14.8 ± 10.3 | .57 | 14.4 ± 10.5 | 14.8 ± 9.9 | .98 |
| Duration of mechanical ventilation, overall, d | 12.7 ± 12.4 | 12.7 ± 13.5 | .50 | 12.4 ± 13.6 | 13.1 ± 12.4 | .08 |
| Duration of mechanical ventilation, among survivors, d | 12.6 ± 12.7 | 11.7 ± 13.8 | .09 | 12.2 ± 14.6 | 12.2 ± 12.0 | .13 |
| ICU-free days | 13.0 ± 9.6 | 13.3 ± 9.9 | .62 | 13.0 ± 10.1 | 13.3 ± 9.4 | .81 |
| ICU length of stay, overall, d | 14.1 ± 11.7 | 14.5 ± 13.6 | .74 | 13.9 ± 12.5 | 14.7 ± 12.7 | .09 |
| ICU length of stay, among survivors, d | 13.9 ± 11.5 | 13.6 ± 13.8 | .15 | 13.5 ± 12.8 | 14.0 ± 12.6 | .12 |
Median BNP concentration was 825 pg/mL (interquartile range, 144-1,574 pg/mL), and median aldosterone concentration was 2.49 ng/dL (interquartile range, 1.1-4.3 ng/dL). Data are given as mean ± SD or as otherwise indicated. APACHE = Acute Physiology and Chronic Health Evaluation; BNP = B-type natriuretic peptide; CVP = central venous pressure; PaO2:FIO2 = ratio of partial pressure of oxygen in arterial blood to the fraction of inspired oxygen; PAOP = pulmonary artery occlusion pressure; PBW = predicted body weight.