Fluid balance and urine volume are independent predictors of mortality in acute kidney injury.

INTRODUCTION: In ICUs, both fluid overload and oliguria are common complications associated with increased mortality among critically ill patients, particularly in acute kidney injury (AKI). Although fluid overload is an expected complication of oliguria, it remains unclear whether their effects on mortality are independent of each other. The aim of this study is to evaluate the impact of both fluid balance and urine volume on outcomes and determine whether they behave as independent predictors of mortality in adult ICU patients with AKI. METHODS: We performed a secondary analysis of data from a multicenter, prospective cohort study in 10 Italian ICUs. AKI was defined by renal sequential organ failure assessment (SOFA) score (creatinine >3.5 mg/dL or urine output (UO) <500 mL/d). Oliguria was defined as a UO <500 mL/d. Mean fluid balance (MFB) and mean urine volume (MUV) were calculated as the arithmetic mean of all daily values. Use of diuretics was noted daily. To assess the impact of MFB and MUV on mortality of AKI patients, multivariate analysis was performed by Cox regression. RESULTS: Of the 601 included patients, 132 had AKI during their ICU stay and the mortality in this group was 50\%. Non-surviving AKI patients had higher MFB (1.31 ± 1.24 versus 0.17 ± 0.72 L/day; P <0.001) and lower MUV (1.28 ± 0.90 versus 2.35 ± 0.98 L/day; P <0.001) as compared to survivors. In the multivariate analysis, MFB (adjusted hazard ratio (HR) 1.67 per L/day, 95\%CI 1.33 to 2.09; <0.001) and MUV (adjusted HR 0.47 per L/day, 95\%CI 0.33 to 0.67; <0.001) remained independent risk factors for 28-day mortality after adjustment for age, gender, diabetes, hypertension, diuretic use, non-renal SOFA and sepsis. Diuretic use was associated with better survival in this population (adjusted HR 0.25, 95\%CI 0.12 to 0.52; <0.001). CONCLUSIONS: In this multicenter ICU study, a higher fluid balance and a lower urine volume were both important factors associated with 28-day mortality of AKI patients

Continuous Real-Time Urine Output Monitoring for Early Detection of Acute Kidney Injury

In critically ill patients, acute kidney injury (AKI) is a common complication. In some cases, oliguria may be the only sign verifying this condition. The consensus definitions of RIFLE and AKIN are based on changes in creatinine and urine output and define classes of severity within AKI. While meaningful change in serum creatinine is often not detectable until 48 h after deterioration in kidney function, urine output is a more rapid physiological parameter and detectable at the patient's bedside. Although urine output is a critical parameter in the intensive care unit, routine urine output measurements are performed manually. As a result, they may not be done timely and may be subject to inaccuracies due to human factors. The URINFO(center dot) system is an innovative digital urine meter that provides continuous minute-to-minute monitoring of urine output, thereby enhancing kidney monitoring and the acquisition of more reliable urine output information in real-time. Consequently, monitoring of urine output with URINFO may enable rapid therapeutic interventions and can be incorporated into patient data systems, thereby improving therapy management. Copyright (C) 2011 S. Karger AG, Base

Extracorporeal CO(2) Removal - A Way to Achieve Ultraprotective Mechanical Ventilation and Lung Support: The Missing Piece of Multiple Organ Support Therapy

Extracorporeal therapies are able to sustain life through different mechanisms. This approach, called multiple organ support therapy, can in fact obtain blood purification by hemodialysis/hemofiltration to replace kidney function, temperature control, electrolyte and acid-base control to mimic homeostatic regulation of the kidney and circulation, fluid balance control to support the right hydration and cardiac performance, cardiac support removing cardiodepressant substances and equilibrating potassium levels, blood detoxification and liver support by coupled plasma filtration and adsorption or direct adsorption on blood (hemoperfusion), immunomodulation and endothelial support in the presence of sepsis by cutting the peaks of pro- and anti-inflammatory mediators, and immunoadsorption or adsorption of specific substances such as endotoxin. A missing piece of this group of therapies was the protective lung support. Today this is made possible by removal of CO, either by complete extracorporeal membrane oxygenation or by using decapneization in conjunction with hemofiltration in a system called DECAP/DECAPSMART. In conclusion, circulating blood outside the body and treating it with different filters or cartridges in a multiple organ support therapy may represent an important support for multiple organ dysfunction conditions induced by sepsis, acute respiratory distress syndrome and in recent times by complicated H1N1-related infections. Copyright (C) 2010 S. Karger AG, Base