Renal Replacement Therapy in the Critical Care Setting

Table 2

Early versus Delayed RRT strategy: a comparison of ELAIN, AKIKI, and IDEAL-ICU studies.

	ELAIN (23)	AKIKI (24)	IDEAL-ICU (25)
Design	RCT	RCT	RCT
Setting	Single centre	Multicentre (31 ICUs)	Multicentre (29 ICUs)
Population	Predominantly postoperative patients; 47% post cardiac surgery.	Predominantly medical patients with septic shock	Patients with septic shock
(i) Main inclusion criteria	(i) KDIGO stage 2; (ii) NGAL>150 mg/ml; (iii) Critical illness including at least one of severe sepsis/vasopressor support/refractory fluid overload/SOFA score >2.	(i) KDIGO stage 3 (Cr>354micromol/L or anuria for >12 hrs or urine output<0.3 ml/kg/hr for 24 hrs); (i) Critical illness (mechanical ventilation or vasopressor)	(i) Failure stage of RIFLE criteria: Oliguria (urine output <0.3 ml per kilogram of body weight per hour for ≥24 hours), Anuria for 12 hours or more, or a serum creatinine level 3 times the baseline level or ≥4 mg per deciliter (≥350 μmol per litre); (ii) Septic shock <48 hrs of commencing vasopressor support
(i) Main exclusion criteria	Preexisting renal disease eGFR <30 ml/min/1.73m2	Preexisting renal disease CrCl < 30 ml/min/1.73m2	End-stage renal disease and obstructive nephropathy
(ii) No. Of patients	231	620	488
Baseline characteristics
(i) SOFA score (early vs delayed)	15.6 vs 16	10.9 vs 10.8	12.2 vs 12.4
(i) APACHE II score (early vs delayed)	30.6 vs 32.7	Not available (NA)	NA
Intervention-early RRT	<8 hrs of AKI KDIGO 2	<6 hrs of AKI KDIGO 3	<12 hrs of failure stage of RIFLE
Control-delayed RRT	<12 hrs of AKI KDIGO 3 or absolute indication	Absolute indications (urea >40 mg/dl, K+>6 mmol/l, pH < 7.15, acute pulmonary oedema, oliguria/anuria >72 hrs)	>48 hrs of failure stage of RIFLE criteria or absolute indications developing
RRT requirement in delayed group (%)	91	51	62
Method of RRT	CVVHDF	Multiple modalities: >50% initially on IHD	Multiple modalities: 45% initially on IHD
Primary outcome
(i) Mortality in early vs delayed RRT	At 90 days: 39.3% vs 54.7%	At 60 days: 48.5% vs 49.7%	At 90 days: 58% vs 54%
(ii) value	0.03	0.79	0.38
Secondary outcome
(i) Duration of RRT early vs delayed (median days)	9 vs 25	NA	4 vs 2
(ii) Ongoing requirement for RRT	At 90 days: 13% vs 15%	At 60 days: 2% vs 5%	At 90 days: 2% vs 3%
Conclusion	Early RRT compared with delayed initiation of RRT reduced mortality over the first 90 days.	No significant difference in mortality between an early and delayed strategy for the initiation of RRT therapy. A delayed strategy averted the need for RRT in a large number of patients.	No significant difference in 90-day mortality between early and strategy of RRT among septic shock patients.