The Assessment of Volume Status by BIA and Lung Ultrasound in Septic AKI Patients Undergoing CRRT

Acute kidney injury(AKI) is one of the most common complications that occur up to 35% of critically ill patients. Septic AKI accounts for one third of them. Patients with septic AKI are widely treated with Continuous renal replacement therapy (CRRT). However, previous studies have hardly documented improvement of mortality in septic AKI patients. Otherwise, Fluid overload in septic shock patients who are undergoing CRRT is proven to be a significant predictor for mortality. Recent studies showed efficacy of bioelectrical impedance analysis and lung ultrasound in assessing fluid status of the patients. Thus, hypothesis of the study is that fluid assessment and control of fluid status using BIA and Lung Ultrasound could be related to the outcome of septic AKI patients who undergo CRRT. In this study, the investigators measure the fluid status of the patients by bioelectrical impedance analysis and lung ultrasound for experimental group, while for control group, fluid status would be determined clinically by the physician. Ultrafiltration rate of experimental group is adjusted to be equal to the value of overhydration measured by BIA.

In this study, investigator measure the fluid status of the patients by bioelectrical impedance analysis and lung ultrasound. The patients are assigned into two groups, BIA and Lung Ultrasound based versus clinical-based assessment group. Ultrafiltration of BIA and Lung Ultrasound based group is adjusted to be equal to the value of over hydration measured only by BIA, not by Lung Ultrasound, because Lung Ultrasound cannot determine exact amount of the patient's fluid excess. Total amount of ultrafiltration will be removed from the patient for three days evenly. On the other hand, Ultrafiltration amount will be decided by the physician in the clinical based group. Amount of fluid removal for a day will be adjusted not to exceed 2000ml, so that total fluid removed from the patient will not exceed 6000ml for three days.

In this study, investigator measure the fluid status of the patients by bioelectrical impedance analysis and lung ultrasound. The patients are assigned into two groups, BIA and Lung Ultrasound based versus clinical-based assessment group. Ultrafiltration of BIA and Lung Ultrasound based group is adjusted to be equal to the value of over hydration measured only by BIA, not by Lung Ultrasound, because Lung Ultrasound cannot determine exact amount of the patient's fluid excess. Total amount of ultrafiltration will be removed from the patient for three days evenly. On the other hand, Ultrafiltration amount will be decided by the physician in the clinical based group. Amount of fluid removal for a day will be adjusted not to exceed 2000ml, so that total fluid removed from the patient will not exceed 6000ml for three days.

Inclusion Criteria: body temperature < 36 °C or > 38 °C heart rate > 90 BPM respiratory rate > 20 or aPaCO2 < 32 mmHg on ABG White blood cell count < 4,000 cells/mm3 or > 12,000 cells/mm3 or band forms (immature white blood cells) ≥10% Evidence of infection WBCs in normally sterile fluid Perforated viscus radiologically proven infection more than Injury stage in AKI according to RIFLE criteria septic AKI which is not explained by other cause patients signed a written informed consent. Exclusion Criteria: Younger than 19 years old, older than 80 years old Previously undergoing dialysis treatment due to ESRD Underlying malignancy, Life expectancy shorter than 3 month AKI due to other than sepsis patients with intracardiac device such as Pacemaker, CRT, ICD