Table 1.

Manipulation of fluid input included studies.

Reference	Study Design	Country	Sample Size	AKI Definition	Population	RRT	Intervention	Comparator	Assessment of Fluid Status	Duration of Intervention	Difference in FB	Outcome Measures
Effat 2021	SC RCT, Unblinded	Egypt	40 (20/20)	Unclear	AKI, ICU	Non-RRT patients	Echo-directed SVV fluid administration	CVP-directed fluid	Incomplete	48 h	Fluid input (2200 mL vs 3700 mL; p < 0.01). No UO or FB data.	ICU LOS (6.4 days vs 12.1 days; p = 0.183). Mortality (10% vs 40%; p = 0.028).
O'Brien 2022	Post hoc analysis of RENAL MC RCT	Australia & New Zealand	771	On CRRT.	ICU; CRRT	RRT as inclusion criteria	1) 20% albumin 2) 20% and 4% albumin	4% albumin	Cumulative fluid balance	Until CRRT cessation or ICU discharge	Daily FB (20% HAS 288 mL, 4% HAS 245 mL, combined HAS 88 mL (p < 0.001). Cumulative FB (1.9 L vs −2.4 vs 1.3; p < 0.01).	Mortality at day 90 (4% HAS 48% vs 20% HAS 52% vs Combined HAS 51%; p = 0.65); RRT dependence at day 90 (6.7% vs 5.3% vs 3.8%; p = 0.59).

Abbreviations: AKI = acute kidney injury; SC = single-centre; MC = multicentre; RCT = randomised controlled trial; CRRT = continuous renal replacement therapy; RRT = renal replacement therapy; ICU = intensive care unit; FB = fluid balance; UO = urine output; RENAL = Randomized Evaluation of Normal versus Augmented Level; HAS = human albumin solution; LOS = length of stay; CVP = central venous pressure.