Table 1.
Population characteristics by lactate levels.
| Initial lactate level (mmol/L) | ||||||||
|---|---|---|---|---|---|---|---|---|
|
| ||||||||
| < 2 (N=5634) | 2 – 2.9 (N=1802) | 3 – 3.9 (N=659) | 4 – 4.9 (N=296) | 5 – 5.9 (N=139) | ≥ 6 (N=266) | P-value | ||
| Demographics | Age (median, mean ± SD) | 55, 54.3 (± 18.5) | 57, 56.5 (± 18.0) | 57, 56.8 (± 17.3) | 56, 56 (± 18.0) | 55, 54.6 (± 18.6) | 57, 56.4 (± 17.7) | <0.0001* |
| Male, n (%) | 2,256 (45.4) | 932 (51.7) | 365 (55.4) | 157 (53.0) | 84 (60.4) | 156 (58.6) | <0.0001 | |
| White, n (%) | 3,593 (63.8) | 1147 (63.7) | 423 (64.3) | 186 (62.8) | 76 (54.7) | 148 (55.6) | 0.02 | |
| Clinical variables | Lactate, mmol/L (median, mean ± SD) | 1.3, 1.3 (± 0.4) | 2.3, 2.4 (± 0.3) | 3.4, 3.4 (± 0.3) | 4.4, 4.4 (± 0.3) | 5.3, 5.4 (± 0.3) | 8.3, 9.4 (± 3.4) | <0.0001* |
| SBP, mmHg (median, mean ± SD) | 134, 135 (± 27) | 132, 134 (± 29) | 127, 130 (± 31) | 125, 126 (± 31) | 127, 126 (± 30) | 121, 126 (± 36) | <0.0001* | |
| Hypotensive (SBP<90) , n (%) | 171 (3.2) | 82 (4.8) | 47 (7.5) | 33 (11.4) | 14 (10.7) | 33 (13.3) | <0.0001 | |
| Sepsis, n (%) | 327 (5.8) | 187 (10.4) | 101 (15.3) | 57 (19.3) | 24 (17.3) | 33 (12.4) | <0.0001 | |
| Severe sepsis, n (%) | 141 (2.5) | 123 (6.8) | 65 (9.9) | 45 (15.2) | 20 (14.4) | 29 (10.9) | <0.0001 | |
| Septic shock, n (%) | 44 (0.8) | 31 (1.7) | 18 (2.7) | 19 (6.4) | 9 (6.5) | 20 (7.5) | <0.0001 | |
| Acute infection, n (%) | 1,456 (25.8) | 471 (26.1) | 179 (27.2) | 75 (25.3) | 31 (22.3) | 45 (16.9) | 0.03 | |
| Acute organ dysfunction, n (%) | 791 (14.0) | 317 (17.6) | 156 (23.7) | 86 (29.1) | 33 (23.7) | 56 (21.1) | <0.0001 | |
| Outcome | Admitted, n (%) | 3,858 (68.5) | 1,420 (78.8) | 567 (86.0) | 274 (92.6) | 124 (89.2) | 237 (89.1) | <0.0001 |
| Admitted to ICU, n (%) | 362 (6.4) | 209 (11.6) | 140 (21.2) | 93 (31.4) | 47 (33.8) | 121 (45.5) | <0.0001 | |
| Mortality, n (%) | 157 (2.8) | 100 (5.6) | 53 (8.0) | 41 (13.9) | 19 (13.7) | 104 (39.1) | <0.0001 | |
*
Based on Kruskal-Wallis (non-parametric) test.
SBP, Systolic Blood Pressure; ICU, Intensive Care Unit; mmol/L, millimoles per liter; mmHg, millimeters of mercury; SD, standard deviation.