TABLE 1.

Representative studies demonstrating negative effect of fluid overload in patients receiving ECMO, CRRT, and those who receive both ECMO and CRRT

STUDY	N	Study Population details	Study Design	Method of FO Measurements	Main Outcomes	Main Findings
Heung et al., 2011 (35)	170	AKI attributed to ATN requiring RST, aged $18 yr, hospitalized	Retrospective, single center	FO% from baseline to RST initiationa	Renal recovery at 1 yr	Higher degree of fluid overload at RST initiation predicts worse renal recovery at 1 yr
Selewski et al., 2011 (28)	113, 50 patients on ECMO	CRRT, 2006–2010, PICU, NICU, cardiac ICU	Retrospective, single center	FO% from ICU admission to CRRT initiationb,c	ICU mortality	Provides evidence for a weight-based definition of FO Higher FO% associated with increased mortality, independent of illness severity score and other clinical factors in patients on ECMO and general pediatric critical care
Sutherland et al., 2010 (25)	297	CRRT (all modalities), aged, 18 yr, all ICUs 2001–2005	Retrospective, using prospectively collected multicenter registry data	FO% from ICU admission to CRRT initiationc	PICU mortality	HiHigher FO% (continuous) and FO% .20% associated with increased mortality, independent of illness severity and other clinical factors
Elbahlawan et al., 2010 (57)	30	CRRT with acute lung injury and ventilation in hematopoietic stem cell transplant, aged #19 yr, ICU, 1994–2006	Retrospective, single center	FO% at 24 h before and 48 h after CRRT initiationc	PaO2/FiO2 ratio, ICU mortality	Both FO and PaO2/FiO2 ratio (oxygenation) improved from 24 h before to 48 h after CRRT initiation PaO2/FiO2 ratio and %FO were inversely associated
Fulop et al., 2010 (31)	81	CRRT (all modalities) with nephrology consultation, aged $18 yr, medical, cardiac, surgical ICUs, 2003–2004	Retrospective, using prospectively collected single-center registry data	%Volume-related weight gain from baseline to RST initiationd	30-d mortality	.10% weight gain associated with mortality, independent of other clinical factors
Hayes et al., 2009 (30)	76	CRRT (all modalities), aged, 18.9 yr, 2000–2005, PICU	Retrospective, single center	FO% from ICU admission to CRRT initiationc	Hospital mortality	FO% .20% associated with increased mortality, independent of illness severity and other clinical factors. FO% .20% also independently associated with prolonged hospitalization, duration of mechanical ventilation, and time to renal recovery
Bouchard et al., 2009 (58)	353	AKI/RST with nephrology consultation, aged $ 18 yr, ICU, 1999–2001e	Retrospective analysis of a prospective multicenter cohort study	FO% at AKI diagnosis, RST initiation, and RST cessationf	30-d and hospital mortality	FO% at RST initiation was associated with mortality after adjustment for illness severity score RST patients with greater days of FO% .10% had increased mortality FO at RST cessation was associated with mortality, adjusted for illness severity score
Blijdorp et al., 2009 (38)	61	Pre-emptive CVVH during ECMO, aged, 28 d, NICU	Retrospective case-comparison study	Average daily fluid balance while on ECMO	Time on ECMO, time from decannulation to extubation	Adding CVVH pre-emptively improves outcomes by decreasing time on ECMO because of improved fluid management
Hoover et al., 2008 (40)	52	All patients receiving ECMO, aged 1 mo-18 yr, PICU, 1992–2006	Retrospective case-matched study (patients receiving CVVH plus ECMO versus ECMO alone)	Fluid balance while on ECMOg	ECMO survival, fluid balance, caloric intake	Use of CVVH with ECMO wasassociated with improved fluid balance, improved caloric intake and decreased diuretic exposure
Gillespie et al., 2004 (27)	88	CVVH for AKI or volume overload, aged #20 yr, 1993–2002	Retrospective, single center	FO% from ICU admission to CVVH initiationc	Mortality, from last known survival status	FO% .10% was associated with increased mortality independent of illness severity and other clinical factors
Foland et al., 2004 (59)	113	CVVH, aged, 18 yr, 1997–2003, PICU, NICU, cardiac ICU	Retrospective, single-center registry	FO% from up to 7 days before CVVH initiationh	PICU mortality	Higher FO% associated with increased mortality, independent of illness severity score and other clinical factors
Goldstein et al., 2001 (22)	21	CWH or CVVHD, aged #18 yr, PICU, 1996–1998	Retrospective, single center	FO% from ICU admission to CVVH initiationc	PICU mortality	FO% at CVVH or CVVHD initiation was associated with increased mortality, independent of illness severity score

ECMO, extracorporeal membrane oxygenation; CRRT, continuous renal replacement therapy; FO, fluid overload; ATN, acute tubular necrosis; RST, renal supportive therapy; PICU, pediatric intensive care unit; NICU, neonatal intensive care unit; ICU, intensive care unit; CVVH, continuous venovenous hemofiltration; CVVHD; continuous venovenous hemodialysis.

^a[(Weight at RST Initiation – Baseline Weight)/Baseline Weight] 3 100%, with baseline weight based on prehospitalization data or hospital admission weight.

^b[(Weight at CRRT Initiation – ICU Admission Weight)/ICU Admission Weight] 3 100.

^c[(Total Fluid Intake – Total Fluid Output in liters, from ICU admission to CRRT)/ICU Admission Weight in kilograms] 3 100.

^d[(Weight at CRRT Initiation – First Available Hospital Weight)/Initial Weight) 3 100.

^eThis study included adults who did and did not receive renal supportive therapy in the ICU. We report only on those who received RST.

^f[(Total Fluid Intake – Total Fluid Output in liters, from 3 d before nephrology consultation to RST or other relevant time point)/Hospital Admission Weight in kilograms) 3 100.

^g[(Total Fluid Intake – Total Fluid Output in liters, from ICU during ECMO)/Weight in kilograms per day on ECMO].

^h[(Total Fluid Intake – Total Fluid Output in liters, from 7 days before CVVH)/estimated dry weight in kilograms] 3 100.