Table 1.

Summary of the designs and key findings of the Early Versus Late Initiation of RRT in critically ill patients with AKI Trial and the Artificial Kidney Initiation in Kidney Injury Trial

Study CharacteristicsELAIN Trial, n=231AKIKI Trial, n=620
No. of sites131
Enrollment criteriaKDIGO stage 2 AKI, plasma NGAL >150 ng/ml, and one of the following: severe sepsis, vasopressor/catecholamine dependence, refractory volume overload, or nonrenal organ dysfunctionKDIGO stage 3 AKI and one of the following: catecholamine infusion and/or invasive mechanical ventilation
RRTCVVHDF at 30 ml/kg per hModality/dosing at discretion of study site
Early RRT, n=112Delayed RRT, n=119Early RRT, n=311Delayed RRT, n=308
Criteria for initiation of RRT<8 h of Reaching KDIGO stage 2 AKI<12 h of Reaching KDIGO stage 3 AKI, BUN>47 mg/dl, serum K+ >6 mmol/L, serum Mg2+ >9.7 mg/dl, or UO<200 ml/12 h<6 h after Reaching KDIGO stage 3 AKIPresence of BUN>112 mg/dl, serum K+ >6 mmol/L, pH<7.15, pulmonary edema caused by fluid overload, or oliguria or anuria >72 h
SOFA score at randomization15.6±2.316.0±2.310.9±3.210.8±3.1
Received RRT (%)112 (100)108 (91)305 (98)157 (51)
Median time from KDIGO stage 2 AKI to RRT (IQR), h6.0 (4.0–7.0)25.5 (18.8–40.3)
Median time from KDIGO stage 3 AKI to RRT (IQR), h4.3 (2.7–5.9)57 (28–83)
Serum creatinine at initiation of RRT, mg/dl1.9±0.62.4±1.03.3±1.45.3±2.3
BUN at initiation of RRT, mg/dl38±1648±2252±2490±34
Serum K+ at initiation of RRT, mmol/L5.1±0.95.1±0.94.4±0.75.1±0.9
Serum tCO2 at initiation of RRT, mmol/L20.9±3.620.7±3.718.9±4.916.6±5.6
Initial modality of RRT, %
 CRRT1001004445
 IHD5655
Mortality, %
 28 d30.440.3 (P=0.11)41.643.5
 60 d38.450.4 (P=0.07)48.549.7 (P=0.79)
 90 d39.354.7 (P=0.03)
Dependence on RRT among survivors (%)
 Day 2818/78 (23.1)26/71 (36.6; P=0.07)22/179 (12.3)17/178 (9.6; P=0.51)
 Day 6011/69 (15.9)14/59 (23.7; P=0.27)3/157 (1.9)8/155 (5.2; P=0.12)
 Day 909/67 (13.4)8/53 (15.1; P=0.80)
  • ELAIN, Early Versus Late Initiation of RRT in Critically Ill Patients with AKI; AKIKI, Artificial Kidney Initiation in Kidney Injury; KDIGO, Kidney Disease Improving Global Outcomes; KDIGO stage 2 AKI, more than twofold increase in serum creatinine concentration or urinary output <0.5 ml/kg per hour for ≥12 hours; NGAL, neutrophil gelatinase–associated lipocalin; KDIGO stage 3 AKI, more than threefold increase in serum creatinine concentration, serum creatinine ≥4 mg/dl with an increase of >0.5 mg/dl, or urinary output <0.3 ml/kg per hour for ≥24 hours or anuria for ≥12 hours; CVVHDF, continuous venovenous hemodiafiltration; K+, potassium; Mg2+, magnesium; UO, urine output; SOFA, sequential organ failure assessment; IQR, interquartile range; tCO2, total carbon dioxide; CRRT, continuous RRT; IHD, intermittent hemodialysis.