Table 3. Patient characteristics at the time of RRT initiation.
| Variables | Total patients | Early RRT (n=77) | Delayed RRT (n=74) | P value |
|---|---|---|---|---|
| Interval from AKI diagnosis to RRT initiation (days) | 0.44 [0.18–1.67] | 0.52 [0.21–1.76] | 0.30 [0.14–1.48] | 0.163 |
| RRT dose (mL/kg/h) | 35.29 [29.10–49.81] | 35.29 [29.31–42.49] | 35.34 [28.57–41.67] | 0.538 |
| RRT mode | ||||
| CVVH | 94 [62] | 49 [64] | 45 [61] | 0.720 |
| CVVHD | 8 [5] | 6 [8] | 2 [3] | 0.163 |
| CVVHDF | 49 [32] | 22 [29] | 27 [36] | 0.299 |
| Scr (μmol/L) | 221.70 [150.28–287.85] | 184.00 [137–239.28] | 254.30 [209–335.80] | <0.01 |
| BUN (mmol/L) | 16.30 [10.90–23.38] | 14.20 [10.33–18.70] | 18.95 [11.40–29.40] | <0.01 |
| eGFR (mL/min/1.73 m2) | 32.34 [22.75–49.14] | 38.08 [27.43–54.94] | 26.49 [17.85–36.39] | <0.01 |
| P/F (mmHg) | 197.00 [133.66–294.13] | 244.10 [156.85–344.78] | 157.30 [105.50–228.50] | <0.01 |
| Peripheral pitting edema | 67 [44] | 21 [27] | 46 [62] | <0.01 |
| UOmean (mL/h) | 27.27 [9.21–65.45] | 27.08 [12.72–64.06] | 27.91 [3.75–66.04] | 0.749 |
| Fluid balance of 24 hours before RRT initiation (mL) | 613.00 [91–1,352.5] | 665.25 [128.5–1,062.8] | 519.30 [53–1,777.2] | 0.800 |
| Cumulative fluid balance from ICU admission to RRT initiation (mL) | 755.00 [164–2,167.48] | 851.40 [269.83–2,113.95] | 519.30 [53–2,198] | 0.380 |
| Mean cumulative fluid balance (mL/h) | 58.64 [5.79–143.08] | 56.26 [12.03–140.99] | 64.58 [3.75–163.64] | 0.967 |
| %FO (%) | 1.08 [0.22–3.11] | 1.36 [0.34–3.08] | 0.76 [0.05–3.14] | 0.358 |
| Dose of norepinephrine (μg/kg/min) | 0.40 [0.1–1.0] | 0.46 [0.05–1.00] | 0.40 [0.10–1.00] | 0.707 |
| MV | 124 [82] | 63 [82] | 61 [82] | 0.922 |
| Vasopressor/inotrope | 100 [66] | 50 [65] | 50 [68] | 0.732 |
| Amiodarone | 19 [13] | 9 [12] | 10 [14] | 0.588 |
| CI (L/min/m2) | 1.92 [1.56–2.35] | 1.87 [1.52–2.33] | 1.97 [1.61–2.45] | 0.271 |
| CVP (mmHg) | 11 [8.13–14] | 10 [8–13.5] | 12 [10–15] | 0.180 |
| Lactate (mmol/L) | 3.10 [1.73–7.0] | 3.20 [1.8–6.3] | 3.05 [1.5–9.2] | 0.583 |
| pH | 7.34 [7.25–7.41] | 7.37 [7.32–7.43] | 7.31 [7.18–7.39] | <0.01 |
| HCO3– (mmol/L) | 19.64±5.85 | 20.16±5.47 | 19.12±6.17 | 0.277 |
| K+ (mmol/L) | 4.43 [4.1–5.0] | 4.30 [3.90–4.83] | 4.70 [4.20–5.10] | <0.01 |
| Serum phosphorus (mmol/L) | 1.58 [1.17–2.29] | 1.46 [1.01–1.92] | 1.98 [1.32–2.54] | <0.01 |
| Stage of AKI | ||||
| Stage 1 | 19 [13] | 12 [16] | 7 [9] | 0.257 |
| Stage 2 | 55 [36] | 42 [55] | 13 [18] | <0.01 |
| Stage 3 | 77 [51] | 23 [30] | 54 [73] | <0.01 |
Data are presented as median [interquartile ranges], n [%], or mean ± SD. UOmean (mL/h) = cumulative urine output from ICU admission to RRT initiation/time from ICU admission to RRT initiation. Mean cumulative fluid balance (mL/h) = cumulative fluid balance from ICU admission to RRT initiation/time from ICU admission to RRT initiation. %FO (%) = [cumulative fluid balance (litre)/ICU admission weight] × 100%. RRT, renal replacement therapy; AKI, acute kidney injury; CVVH, continuous veno-venous hemofiltration; CVVHD, continuous veno-venous hemodialysis; CVVHDF, continuous veno-venous hemodiafiltration; Scr, serum creatinine; BUN, blood urea nitrogen; eGFR, estimated glomerular filtration rate; P/F, PaO2/FiO2; ICU, intensive care unit; FO, fluid overload; MV, mechanical ventilation; CI, cardiac index; CVP, central venous pressure.