Table 2.
Clinical Outcomes
| Outcome* | n | Balanced Crystalloids (n = 824) | Saline (n = 817) | Adjusted OR (95% CI)† |
|---|---|---|---|---|
| Primary outcome | ||||
| 30-d in-hospital mortality, n (%) | 1,641 | 217 (26.3) | 255 (31.2) | 0.74 (0.59 to 0.93) |
| Additional clinical outcomes | ||||
| 60-d in-hospital mortality, n (%) | 1,641 | 241 (29.2) | 269 (32.9) | 0.80 (0.64 to 1.01) |
| ICU-free days‡, median (IQR) | 1,641 | 23 (0 to 26) | 23 (0 to 26) | 1.15 (0.97 to 1.38) |
| Mean ± SD | — | 17 ± 11 | 16 ± 12 | — |
| Ventilator-free days‡, median (IQR) | 1,641 | 27 (0 to 28) | 26 (0 to 28) | 1.37 (1.12 to 1.68) |
| Mean ± SD | — | 19 ± 12 | 18 ± 13 | — |
| Vasopressor-free days‡, median (IQR) | 1,641 | 27 (0 to 28) | 27 (0 to 28) | 1.25 (1.02 to 1.54) |
| Mean ± SD | — | 20 ± 12 | 19 ± 13 | — |
| Renal replacement therapy–free days‡, median (IQR) | 1,641 | 28 (0 to 28) | 28 (0 to 28) | 1.35 (1.08 to 1.69) |
| Mean ± SD | — | 20 ± 12 | 19 ± 13 | — |
| Additional renal outcomes§ | ||||
| Major adverse kidney event within 30 d, n (%)|| | 1,641 | 292 (35.4) | 328 (40.1) | 0.78 (0.63 to 0.97) |
| Receipt of new renal replacement therapy, n (%)§ | 1,458 | 54 (7.4) | 75 (10.3) | 0.71 (0.48 to 1.04) |
| Final creatinine ≥200% of baseline, n (%) | 1,458 | 164 (22.4) | 162 (22.3) | 0.99 (0.76 to 1.28) |
| Stage II or greater AKI developing after ICU admission, n (%)¶ | 1,458 | 201 (27.4) | 231 (31.9) | 0.79 (0.63 to 1.00) |
| Creatinine**, mg/dl | 1,458 | |||
| Highest before discharge or 30 d | — | 1.58 (0.87 to 3.00) | 1.59 (0.93 to 2.97) | 0.95 (0.79 to 1.13) |
| Change from baseline to highest value | — | 0.18 (−0.07 to 1.13) | 0.23 (−0.07 to 1.20) | 0.99 (0.82 to 1.18) |
| Final value before discharge or 30 d | — | 0.94 (0.69 to 1.77) | 0.95 (0.71 to 1.80) | 0.97 (0.81 to 1.16) |
Definition of abbreviations: AKI = acute kidney injury; CI = confidence interval; IQR = interquartile range; OR = odds ratio.
Continuous data are presented as median (25th percentile to 75th percentile) or mean ± SD.
The adjusted OR is for the balanced crystalloids group compared with the saline group. Categorical outcomes are compared between study groups using a logistic regression model accounting for covariates (age, sex, race, source of admission, use of mechanical ventilation, and use of vasopressors). Continuous outcomes are compared between groups using a proportional odds model adjusting for the same variables.
ICU-free, ventilator-free, vasopressor-free, and renal replacement therapy–free days refer to the number of days alive and free from the specified therapy in the first 28 days after ICU admission. ORs greater than 1.0 indicate a better outcome (i.e., more days alive and free from the specified therapy) with balanced crystalloids compared with saline.
Receipt of new renal replacement therapy and additional renal outcomes based on creatinine measurements are among the 1,458 patients (733 in the balanced crystalloid group and 725 in the saline group) not known to have received renal replacement therapy before ICU admission.
Major adverse kidney events within 30 days is the composite of death, receipt of new renal replacement therapy, or final creatinine greater than or equal to 200% baseline, all censored at the first of hospital discharge or 30 days after ICU admission.
Stage II or greater AKI developing after ICU admission is defined using the Kidney Disease: Improving Global Outcomes creatinine criteria (31) as any creatinine value between ICU admission and discharge or 30 days that is 1) increased at least 0.3 mg/dl from a preceding postenrollment value and 2) at least 200% of the baseline value, at least 200% of a preceding postenrollment value, or at least 4.0 mg/dl; or new receipt of renal replacement therapy.
Among patients who had not received prior renal replacement therapy, plasma creatinine was measured a mean of 8.0 times between ICU admission and the first of discharge or 30 days in each group; plasma creatinine was not measured between ICU admission and the first of discharge or 30 days for 8 patients (1.0%) in the balanced crystalloid group and 9 patients (1.1%) in the saline group.