Fluid overload is an independent risk factor for acute kidney injury in critically Ill patients: results of a cohort study

Abstract

BackgroundAcute Kidney injury (AKI) is common and increases mortality in the intensive care unit (ICU). We carried out this study to explore whether fluid overload is an independent risk factor for AKI.MethodsSingle-center prospective, observational study. Consecutively admitted, ICU patients were followed for development of AKI. Intravenous fluid volumes, daily fluid balances were measured, hourly urine volumes, daily creatinine levels were recorded.ResultsThree hundred thirty nine patients were included; AKI developed in 141 (41.6%) patients; RISK in 27 (8%) patients; INJURY in 25 (7%); FAILURE in 89 (26%) by the RIFLE criteria. Fluid balance was significantly higher in patients with AKI; 1755 ± 2189 v/s 924 ± 1846 ml, p < 0.001 on ICU day 1. On multivariate regression analysis, a net fluid balance in first 24 h of ICU admission, OR 1.02 (95% CI 1.01,1.03 p = 0.003), percentage of fluid accumulation adjusted for body weight OR1.009 (95% CI 1.001,1.017, p = 0.02), fluid balance in first 24 h of ICU admission with serum creatinine adjusted for fluid balance, OR 1.024 (95% CI 1.012,1,035, p = 0.005), Age, OR 1.02 95% CI 1.01,1.03, p < 0.001, CHF, OR 3.1 (95% CI 1.16,8.32, p = 0.023), vasopressor requirement on ICU day one, OR 1.9 (95% CI 1.13,3.19, p = 0.014) and Colistin OR 2.3 (95% CI 1.3, 4.02, p < 0.001) were significant predictors of AKI. There was no significant association between fluid type; Chloride-liberal, Chloride-restrictive, and AKI.ConclusionsFluid overload is an independent risk factor for AKI.

Euvolemia—A critical target in the management of acute kidney injury

“…In adult patients admitted to the ICU with sepsis, Van Biesen et al showed that a positive fluid balance on day 1 was associated with an increased risk of AKI . This was confirmed in a single‐center prospective observational study which demonstrated that positive fluid balance in the first 24 hours of ICU admission was associated with a significant increase in AKI . In patients admitted to Guy's & St. Thomas Hospital with stage 1 AKI, positive fluid balance was also found to be an independent predictor of progression to stage 3 AKI …”

“…9 This was confirmed in a single-center prospective observational study which demonstrated that positive fluid balance in the first 24 hours of ICU admission was associated with a significant increase in AKI. 10 In patients admitted to Guy's & St. Thomas Hospital with stage 1 AKI, positive fluid balance was also found to be an independent predictor of progression to stage 3 AKI. 11 Even after adjusting for severity of illness, numerous studies in both children and adults have demonstrated an association between fluid overload and mortality in patients with AKI.…”

Recommendations for active correction of hypernatremia in volume-resuscitated shock or sepsis patients should be taken with a grain of salt: A systematic review

“…Given the demonstrated morbidity associated with hypervolemia in critically ill patients, 27 , 43 – 45 the established benefits of “deresuscitation” in such patients, 43 , 46 and the absence of evidence of improved outcomes with volume administration to treat hypernatremia in resuscitated patients, we believe that a cautiously “salt-tolerant/fluid-restricted” therapeutic strategy is at least as well supported by existing research as is the dominant “salt-intolerant/fluid-liberal” paradigm.…”

Approach to Fluid Therapy in the Acute Setting

“…In managing intra-abdominal hypertension and abdominal compartment syndrome, poorer outcomes have been attributed to fluid overload [89,90], a phenomenon linked to capillary leak and tissue edema. While fluid is often aggressively given to prevent AKI, the association between fluid overload and poorer renal outcomes has been evident [86,91,92], prompting questions on the cause-effect relationship between fluid overload and AKI [93].…”