Epidemiological Studies of ICU Patients with Acute Kidney Injury

ObjectiveRetrospective analysis of clinical data of intensive care unit (ICU) patients with acutekidney injury (AKI), summarize the etiology, clinical features, prognosis and influencingfactors, in order to enhance early diagnosis and treatment of AKI,and improve theprognosis of patients with AKI.MethodsRetrospective analysis1692cases of severe clinical data,from January2009toDecember31,2011who stay at the ICU of the First Affiliated Hospital of SuzhouUniversity, except patients in the ICU time <24hours and admitted to the ICU again,except the past patients who have chronic renal insufficiency and who with kidney surgerypatients and incomplete information.1134patients will be selected by AKI network (AKIN)standards are divided into non-AKI group and AKI group (divided into Phase I group-risk,phase II group-injury and III group-failure), comparison of variables between the twogroups by t-test and chi-square test, then the logistic regression analysis to filter out of AKIrisk factors.Resuls1. Selected cases is divided into no renal injury (NAKI) group of740cases, the AKIgroup of394cases, which composed by AKI I group of238cases, AKI II group of112cases and AKI III group of44patients. AND AKI incidence rate is34.7%. Every group ofAKI, number of organ failure>2, septic shock incidence, mechanical ventilation, use ofvasoactive drugs proportion significantly higher than the the NAKI group (P <0.01); AKIgroup patients have a higher SOFA and APACHEII rating, and higher serum potassiumconcentration than the patients without AKI patients (P <0.01); but AKI I and AKI IIIgroup have lower arterial oxygen than the other two (P <0.05). This study within threeyears of AKI incidence has increased year by year, and the annual male patients numbermore than female patients, and respectively male to female ratio of1.02:1,1.21:1,1.24:1 (P <0.05).2. By lesion etiology Category: prerenal accounted37.2%, mainly due to heart failure,followed by traumatic bleeding;194cases from rennal，renal tubular、 interstitial diseasemostly accounted39.8%, mainly due to drugs (31cases), severe infection (79cases),tumor (n=5);13.5%was from post-renal disease because of urinary stones, prostatedisease, cancer, etc. Analysed etiology by age,126caseswas youth, of which prerenal21.4%, and post-renal (4.8%); old group accounted for37.3%from total number ofpatients with AKI, prerenal (42.2%), and post-renal (24.5%); Age≥80have121cases,prerenal (47.9%),rennal accounted43.0%, and post-renal (9.1%); The data show that: inthe youth group,renal reasons is the mostly reason,in elderly, prerenal and post-renal is themain parts,the difference between two was statistically significant (P <0.05).3、Prognosis:①Etiology and prognosis: This study43patients cured, improved116patients,235patients died, total mortality was59.6%; prerenal death29cases;，renalpatients death42.9%, post-rennal37cases death rennal disesse has the highest fatality rate,but the difference was not statistically significant;②Staging and prognosis: total mortalityof ICU patients were34.2%, AKI mortality was59.6%significantly higher NAKI (20.7%)(P <0.01); mortality in patients significantly increased with AKI stage increased: AKI I48.5%, AKI II76.8%, AKI III77.3%. AKI survival group of hospital stay time wassignificantly longer than NAKI survival group hospitalization time.③Age and prognosis:Old age group were cured compared with youth group is low, the elderly group has thehigher mortality than the young, which the highest mortality rate is elderly group,followed old age, a significant difference among the three groups (P <0.05);4、Risk factors: Age (>60years), APACHEII score (>20points), septic shock, organfailure, type antibiotics, mechanical ventilation, coma, hypotension and oliguria significantmortality in acute kidney injury (P <0.05). Septic shock is the most common cause of death.Followed by heart failure, central nervous system failure and liver failure, directly relatedto the death of patients with acute renal failure accounted3.9%. Multivariate regressionanalysis showed that mechanical ventilation, septic shock were independent risk factors ofICU patients developed AKI.ConclusionsThe incidence of acute kidney injury in the ICU is still high, Up to34.7%, and the mortality rate is higher than NAKI，ICU hospitalized with AKI survival of patients with anaverage length of stay is longer than Naki group. AKI number of organ failure in patientswith>2, septic shock incidence of mechanical ventilation, use of vasoactive drugsproportion SOFA and APACHEII score, serum potassium concentration were significantlyhigher than the the Naki group. the etiology of AKI patients renal reasons is the most theproportion，and the renal reason highest fatality rate, but the difference was not statisticallysignificant. Each age group, renal reasons is mostly of youth group AKI， The elderlygroup has the highest mortality rate, the worst prognosis. Mechanical ventilation and septicshock a significant increase in the incidence AKI ICU patients is an independent risk factorAKI.