The Influence Of Positive Fluid Balance On Prognosis Of Patients With Severe Sepsis-Induced Acute Kidney Injury

ObjectiveTo investigate the influence of positive fluid balance on prognosis of patientswith severe sepsis-induced acute kidney injury.MethodsA retrospective controlled study was conducted on the clinical data of164adultpatients with severe sepsis in intensive care unit(ICU) of Guangzhou First MunicipalHospital from January2011to August2013. According to the occurrence of AKI, thepatients were divided into severe sepsis AKI group（n=90) and non-severe sepsis AKIgroup (n=74). In the severe sepsis AKI group, it was further divided into survivalgroup (n=64) and non-survival group (n=26) according to the final outcome. For theseanalyses, early AKI was defined as it occurred within the first48hours of ICUadmission, and late AKI as it occurring more than48hours after ICU admission.Early CRRT was defined as patients with severe sepsis were treated by CRRT in thefirst48hours of ICU admission, and late CRRT was applied more than48hours afterICU admission. The relation between positive fluid balance and the prognosis of acutekidney injury (AKI) patients with severe sepsis was evaluated by the patient’s vitalsigns, laboratory parameters, fluid balance, APACHE Ⅱscore and other indicators. Inorder to assess the factor of mortality at28days in AKI patients with severe sepsis,multivariate Cox regression analysis was applied, which included the days of ICUadmission, Creatinine values, urine,oxygenation index, APAPCHE Ⅱscore, SOFA score, the mean fluid balance, use of vasopressors or not, and use of CRRT or not.Results①28-day mortality in severe sepsis AKI group was significantly higher than thatin non-severe sepsis AKI group (71.10%vs35.14%, P=0.00).Compared withnon-AKI patients group, the disease is worse in AKI group, which showed higherAPACHE Ⅱscore (24.2±4.54vs20.84±4.82, P=0.00), higher SOFA score (8.3±3.05vs6.41±2.62, P=0.00), more daily average fluid balance (977.09±566.06vs466.98±515.23,P=0.00),and less urine output (1457.58±789.99vs2068.59±499.39, P=0.00). AKI patients who used more diuretics (80vs50, P=0.00), theirlung oxygenation index is worse (218.24±73.77vs258.53±70.26, P=0.00).②I n Cox regression analysis, the independent risk factors for28-day mortalityin patients with severe sepsis includes creatinine value, the mean fluid balance andSOFA score.③There is no statistically significant difference in the age and severity betweensurvival group and non-survival group of patients with severe sepsis-induced acutekidney injury, but the patients in non-survival group have more volume overload.Compared with the survival group, it has higher mean fluid balance (1112.12±546.85vs644.69±474.93, P=0.00), and less urine output (1224.07±708.79vs2032.36±723.53, P=0.00).④There is no significant difference on mortality between early and late CRRTduring ICU treatment. However, the average daily fluid balance of late CRRT patientswas significantly greater than that of early CRRT patients (1178.81±397.03vs287.22±433.53, P=0.00) and the lung oxygenation index of late CRRT patients wassignificantly worse than that of early CRRT patients.⑤The related variables to28-day mortality in AKI patients with severe sepsisincludes CRRT treatment, oxygenation index and the average daily fluid balance>500ml.Among them, fluid balance>500ml is an independent risk factor for AKIpatients with severe sepsis. Their prognosis is worse if they have larger positive fluidbalance. CRRT is the protective factor which can affects the prognosis of patients withsevere sepsis AKI. ConclusionPatients with severe sepsis induced AKI have a high mortality. If earlyidentification of AKI, taking appropriate measures to protect kidney function helps toimprove the prognosis of patients with severe sepsis. Fluid balance>500ml is anindependent risk factor for AKI patients with severe sepsis. Their prognosis wasworse if they have larger positive fluid balance. Early CRRT could reduce fluidretention in patients of renal failure and improve oxygenation index.